Fix a bunch of warnings

Add numbers parsing
Add integer traits
2025-07-06 17:05:36 +02:00 · 2025-07-04 20:44:04 +02:00 · 2025-07-04 18:22:03 +02:00 · 2025-07-03 18:35:25 +02:00 · 2025-07-03 18:34:45 +02:00 · 2025-06-26 18:25:00 +02:00
99 changed files with 10039 additions and 861 deletions
--- a/.bazelrc
+++ b/.bazelrc
@ -1,11 +1,14 @@
+common --registry=https://bcr.bazel.build/
+common --registry=https://bazel.stevenlr.com/registry/
+
 startup --windows_enable_symlinks
 build:windows --enable_runfiles=true

+build --enable_platform_specific_config
 build --build_python_zip=false

 build:windows  --extra_execution_platforms=//:x64_windows-clang-cl
-# @Todo(bazel) We should be able to use @local_config_cc...
-build:windows  --extra_toolchains=@@rules_cc++cc_configure_extension+local_config_cc//:cc-toolchain-x64_windows-clang-cl
+build:windows  --extra_toolchains=@local_config_cc//:cc-toolchain-x64_windows-clang-cl

 build:linux    --repo_env=CC=clang

@ -24,14 +27,15 @@ build --cxxopt=-Wno-extra-semi
 build --cxxopt=-Wno-global-constructors
 build --cxxopt=-Wno-unsafe-buffer-usage
 build --cxxopt=-Wno-covered-switch-default
+build --cxxopt=-Wno-unused-command-line-argument

 build:windows_san --config=windows
 build:windows_san --copt=-fno-sanitize-ignorelist
 build:windows_san --copt=-fsanitize=address
 build:windows_san --copt=-fsanitize=undefined
 build:windows_san --copt=-fno-sanitize-recover=all
-build:windows_san --linkopt=clang_rt.asan-x86_64.lib
-build:windows_san --copt=/MT
+build:windows_san --linkopt=clang_rt.asan_dynamic-x86_64.lib
+build:windows_san --linkopt=clang_rt.asan_dynamic_runtime_thunk-x86_64.lib

 build:linux_san --config=linux
 build:linux_san --copt=-fsanitize=address
--- a/.clang-tidy
+++ b/.clang-tidy
@ -1,34 +1,24 @@
 Checks:
-  - "hicpp-*"
-  - "cppcoreguidelines-*"
-  - "misc-*"
-  - "clang-analyzer-*"
-  - "-misc-include-cleaner"
-  - "performance-*"
-  - "readability-*"
-  - "-*-named-parameter"
-  - "-*-avoid-do-while"
-  - "-*-magic-numbers"
-  - "-*-identifier-length"
-  - "-*-union-access"
-  - "-*-vararg"
-  - "-*-macro-usage"
-  - "-*-non-private-member-variables-in-classes"
-  - "-*-avoid-non-const-global-variables"
-  - "-*-missing-std-forward"
-  - "-*-owning-memory"
-  - "-*-no-malloc"
+  - "*"
+  - "-llvm*"
+  - "-altera*"
+  - "-fuchsia*"
+  - "-*-use-trailing-return-type"
+  - "-readability-identifier-length"
+  - "-cppcoreguidelines-macro-usage"
  - "-*-avoid-c-arrays"
+  - "-*-non-private-member-variables-in-classes"
  - "-*-use-anonymous-namespace"
-  - "-*-reinterpret-cast"
-  - "-*-noexcept-swap"
-  - "-*-noexcept-move"
-  - "-*-noexcept-move-constructor"
-  - "-*-noexcept-move-operations"
-  - "-*-bounds-array-to-pointer-decay"
-  - "-*-no-array-decay"
+  - "-cert-err58-cpp"
+  - "-*noexcept*"
+  - "-*-magic-numbers"
+  - "-*-named-parameter"
+  - "-misc-include-cleaner"
+  - "-google-runtime-int"
+  - "-bugprone-easily-swappable-parameters"
  - "-*-signed-bitwise"
-  - "-readability-use-anyofallof"
-  - "-readability-function-cognitive-complexity"
+  - "-*-avoid-do-while"
+  - "-cppcoreguidelines-pro-type-union-access"
+  - "-*-copy-assignment-signature"
+  - "-*-unconventional-assign-operator"
  - "-readability-math-missing-parentheses"
-  - "-*-rvalue-reference-param-not-moved"
--- a/.clangd
+++ b/.clangd
@ -0,0 +1,7 @@
+---
+CompilerFlags:
+  Add:
+    - "-Wall"
+Diagnostics:
+  ClangTidy:
+    FastCheckFilter: None
--- a/MODULE.bazel
+++ b/MODULE.bazel
@ -2,19 +2,17 @@
 #
 # SPDX-License-Identifier: BSD-3-Clause

-module(name = "asl")
+module(name = "asl", version = "0.4.0")

-bazel_dep(name = "platforms", version = "0.0.10")
-bazel_dep(name = "rules_cc", version = "0.0.17")
+bazel_dep(name = "platforms", version = "0.0.11")
 bazel_dep(name = "rules_license", version = "1.0.0")

-bazel_dep(name = "hedron_compile_commands", dev_dependency = True)
-git_override(
-    module_name = "hedron_compile_commands",
-    remote = "https://github.com/hedronvision/bazel-compile-commands-extractor.git",
-    commit = "4f28899228fb3ad0126897876f147ca15026151e",
-)
+bazel_dep(name = "rules_cc", version = "0.1.1")
+cc_configure = use_extension("@rules_cc//cc:extensions.bzl", "cc_configure_extension")
+use_repo(cc_configure, "local_config_cc")

-bazel_dep(name = "rules_python", version = "1.1.0")
+bazel_dep(name = "hedron_compile_commands", version = "0.1.0", dev_dependency = True)
+
+bazel_dep(name = "rules_python", version = "1.3.0")
 python = use_extension("@rules_python//python/extensions:python.bzl", "python")
 python.toolchain(python_version = "3.13", is_default = True)
--- a/MODULE.bazel.lock
+++ b/MODULE.bazel.lock
@ -1,6 +1,9 @@
 {
  "lockFileVersion": 18,
  "registryFileHashes": {
+    "https://bazel.stevenlr.com/registry/bazel_registry.json": "8a28e4aff06ee60aed2a8c281907fb8bcbf3b753c91fb5a5c57da3215d5b3497",
+    "https://bazel.stevenlr.com/registry/modules/hedron_compile_commands/0.1.0/MODULE.bazel": "5623ba8f732a01246c388bccebf924357e452314a178f179d3b375b623d5a359",
+    "https://bazel.stevenlr.com/registry/modules/hedron_compile_commands/0.1.0/source.json": "c55f6caa3eb9fb027af66949c23ca537214eb32b0316ae95bcc496f3cd8406b9",
    "https://bcr.bazel.build/bazel_registry.json": "8a28e4aff06ee60aed2a8c281907fb8bcbf3b753c91fb5a5c57da3215d5b3497",
    "https://bcr.bazel.build/modules/abseil-cpp/20210324.2/MODULE.bazel": "7cd0312e064fde87c8d1cd79ba06c876bd23630c83466e9500321be55c96ace2",
    "https://bcr.bazel.build/modules/abseil-cpp/20211102.0/MODULE.bazel": "70390338f7a5106231d20620712f7cccb659cd0e9d073d1991c038eb9fc57589",
@ -17,7 +20,8 @@
    "https://bcr.bazel.build/modules/bazel_features/1.18.0/MODULE.bazel": "1be0ae2557ab3a72a57aeb31b29be347bcdc5d2b1eb1e70f39e3851a7e97041a",
    "https://bcr.bazel.build/modules/bazel_features/1.19.0/MODULE.bazel": "59adcdf28230d220f0067b1f435b8537dd033bfff8db21335ef9217919c7fb58",
    "https://bcr.bazel.build/modules/bazel_features/1.21.0/MODULE.bazel": "675642261665d8eea09989aa3b8afb5c37627f1be178382c320d1b46afba5e3b",
-    "https://bcr.bazel.build/modules/bazel_features/1.21.0/source.json": "3e8379efaaef53ce35b7b8ba419df829315a880cb0a030e5bb45c96d6d5ecb5f",
+    "https://bcr.bazel.build/modules/bazel_features/1.30.0/MODULE.bazel": "a14b62d05969a293b80257e72e597c2da7f717e1e69fa8b339703ed6731bec87",
+    "https://bcr.bazel.build/modules/bazel_features/1.30.0/source.json": "b07e17f067fe4f69f90b03b36ef1e08fe0d1f3cac254c1241a1818773e3423bc",
    "https://bcr.bazel.build/modules/bazel_features/1.4.1/MODULE.bazel": "e45b6bb2350aff3e442ae1111c555e27eac1d915e77775f6fdc4b351b758b5d7",
    "https://bcr.bazel.build/modules/bazel_features/1.9.1/MODULE.bazel": "8f679097876a9b609ad1f60249c49d68bfab783dd9be012faf9d82547b14815a",
    "https://bcr.bazel.build/modules/bazel_skylib/1.0.3/MODULE.bazel": "bcb0fd896384802d1ad283b4e4eb4d718eebd8cb820b0a2c3a347fb971afd9d8",
@ -39,11 +43,13 @@
    "https://bcr.bazel.build/modules/googletest/1.14.0.bcr.1/MODULE.bazel": "22c31a561553727960057361aa33bf20fb2e98584bc4fec007906e27053f80c6",
    "https://bcr.bazel.build/modules/googletest/1.14.0.bcr.1/source.json": "41e9e129f80d8c8bf103a7acc337b76e54fad1214ac0a7084bf24f4cd924b8b4",
    "https://bcr.bazel.build/modules/googletest/1.14.0/MODULE.bazel": "cfbcbf3e6eac06ef9d85900f64424708cc08687d1b527f0ef65aa7517af8118f",
+    "https://bcr.bazel.build/modules/hedron_compile_commands/0.1.0/MODULE.bazel": "not found",
    "https://bcr.bazel.build/modules/jsoncpp/1.9.5/MODULE.bazel": "31271aedc59e815656f5736f282bb7509a97c7ecb43e927ac1a37966e0578075",
    "https://bcr.bazel.build/modules/jsoncpp/1.9.5/source.json": "4108ee5085dd2885a341c7fab149429db457b3169b86eb081fa245eadf69169d",
    "https://bcr.bazel.build/modules/libpfm/4.11.0/MODULE.bazel": "45061ff025b301940f1e30d2c16bea596c25b176c8b6b3087e92615adbd52902",
    "https://bcr.bazel.build/modules/platforms/0.0.10/MODULE.bazel": "8cb8efaf200bdeb2150d93e162c40f388529a25852b332cec879373771e48ed5",
-    "https://bcr.bazel.build/modules/platforms/0.0.10/source.json": "f22828ff4cf021a6b577f1bf6341cb9dcd7965092a439f64fc1bb3b7a5ae4bd5",
+    "https://bcr.bazel.build/modules/platforms/0.0.11/MODULE.bazel": "0daefc49732e227caa8bfa834d65dc52e8cc18a2faf80df25e8caea151a9413f",
+    "https://bcr.bazel.build/modules/platforms/0.0.11/source.json": "f7e188b79ebedebfe75e9e1d098b8845226c7992b307e28e1496f23112e8fc29",
    "https://bcr.bazel.build/modules/platforms/0.0.4/MODULE.bazel": "9b328e31ee156f53f3c416a64f8491f7eb731742655a47c9eec4703a71644aee",
    "https://bcr.bazel.build/modules/platforms/0.0.5/MODULE.bazel": "5733b54ea419d5eaf7997054bb55f6a1d0b5ff8aedf0176fef9eea44f3acda37",
    "https://bcr.bazel.build/modules/platforms/0.0.6/MODULE.bazel": "ad6eeef431dc52aefd2d77ed20a4b353f8ebf0f4ecdd26a807d2da5aa8cd0615",
@ -69,12 +75,12 @@
    "https://bcr.bazel.build/modules/rules_cc/0.0.14/MODULE.bazel": "5e343a3aac88b8d7af3b1b6d2093b55c347b8eefc2e7d1442f7a02dc8fea48ac",
    "https://bcr.bazel.build/modules/rules_cc/0.0.15/MODULE.bazel": "6704c35f7b4a72502ee81f61bf88706b54f06b3cbe5558ac17e2e14666cd5dcc",
    "https://bcr.bazel.build/modules/rules_cc/0.0.16/MODULE.bazel": "7661303b8fc1b4d7f532e54e9d6565771fea666fbdf839e0a86affcd02defe87",
-    "https://bcr.bazel.build/modules/rules_cc/0.0.17/MODULE.bazel": "2ae1d8f4238ec67d7185d8861cb0a2cdf4bc608697c331b95bf990e69b62e64a",
-    "https://bcr.bazel.build/modules/rules_cc/0.0.17/source.json": "4db99b3f55c90ab28d14552aa0632533e3e8e5e9aea0f5c24ac0014282c2a7c5",
    "https://bcr.bazel.build/modules/rules_cc/0.0.2/MODULE.bazel": "6915987c90970493ab97393024c156ea8fb9f3bea953b2f3ec05c34f19b5695c",
    "https://bcr.bazel.build/modules/rules_cc/0.0.6/MODULE.bazel": "abf360251023dfe3efcef65ab9d56beefa8394d4176dd29529750e1c57eaa33f",
    "https://bcr.bazel.build/modules/rules_cc/0.0.8/MODULE.bazel": "964c85c82cfeb6f3855e6a07054fdb159aced38e99a5eecf7bce9d53990afa3e",
    "https://bcr.bazel.build/modules/rules_cc/0.0.9/MODULE.bazel": "836e76439f354b89afe6a911a7adf59a6b2518fafb174483ad78a2a2fde7b1c5",
+    "https://bcr.bazel.build/modules/rules_cc/0.1.1/MODULE.bazel": "2f0222a6f229f0bf44cd711dc13c858dad98c62d52bd51d8fc3a764a83125513",
+    "https://bcr.bazel.build/modules/rules_cc/0.1.1/source.json": "d61627377bd7dd1da4652063e368d9366fc9a73920bfa396798ad92172cf645c",
    "https://bcr.bazel.build/modules/rules_foreign_cc/0.9.0/MODULE.bazel": "c9e8c682bf75b0e7c704166d79b599f93b72cfca5ad7477df596947891feeef6",
    "https://bcr.bazel.build/modules/rules_fuzzing/0.5.2/MODULE.bazel": "40c97d1144356f52905566c55811f13b299453a14ac7769dfba2ac38192337a8",
    "https://bcr.bazel.build/modules/rules_fuzzing/0.5.2/source.json": "c8b1e2c717646f1702290959a3302a178fb639d987ab61d548105019f11e527e",
@ -88,10 +94,10 @@
    "https://bcr.bazel.build/modules/rules_java/7.2.0/MODULE.bazel": "06c0334c9be61e6cef2c8c84a7800cef502063269a5af25ceb100b192453d4ab",
    "https://bcr.bazel.build/modules/rules_java/7.3.2/MODULE.bazel": "50dece891cfdf1741ea230d001aa9c14398062f2b7c066470accace78e412bc2",
    "https://bcr.bazel.build/modules/rules_java/7.6.1/MODULE.bazel": "2f14b7e8a1aa2f67ae92bc69d1ec0fa8d9f827c4e17ff5e5f02e91caa3b2d0fe",
+    "https://bcr.bazel.build/modules/rules_java/8.12.0/MODULE.bazel": "8e6590b961f2defdfc2811c089c75716cb2f06c8a4edeb9a8d85eaa64ee2a761",
+    "https://bcr.bazel.build/modules/rules_java/8.12.0/source.json": "cbd5d55d9d38d4008a7d00bee5b5a5a4b6031fcd4a56515c9accbcd42c7be2ba",
    "https://bcr.bazel.build/modules/rules_java/8.3.2/MODULE.bazel": "7336d5511ad5af0b8615fdc7477535a2e4e723a357b6713af439fe8cf0195017",
    "https://bcr.bazel.build/modules/rules_java/8.5.1/MODULE.bazel": "d8a9e38cc5228881f7055a6079f6f7821a073df3744d441978e7a43e20226939",
-    "https://bcr.bazel.build/modules/rules_java/8.6.1/MODULE.bazel": "f4808e2ab5b0197f094cabce9f4b006a27766beb6a9975931da07099560ca9c2",
-    "https://bcr.bazel.build/modules/rules_java/8.6.1/source.json": "f18d9ad3c4c54945bf422ad584fa6c5ca5b3116ff55a5b1bc77e5c1210be5960",
    "https://bcr.bazel.build/modules/rules_jvm_external/4.4.2/MODULE.bazel": "a56b85e418c83eb1839819f0b515c431010160383306d13ec21959ac412d2fe7",
    "https://bcr.bazel.build/modules/rules_jvm_external/5.1/MODULE.bazel": "33f6f999e03183f7d088c9be518a63467dfd0be94a11d0055fe2d210f89aa909",
    "https://bcr.bazel.build/modules/rules_jvm_external/5.2/MODULE.bazel": "d9351ba35217ad0de03816ef3ed63f89d411349353077348a45348b096615036",
@ -121,8 +127,8 @@
    "https://bcr.bazel.build/modules/rules_python/0.31.0/MODULE.bazel": "93a43dc47ee570e6ec9f5779b2e64c1476a6ce921c48cc9a1678a91dd5f8fd58",
    "https://bcr.bazel.build/modules/rules_python/0.4.0/MODULE.bazel": "9208ee05fd48bf09ac60ed269791cf17fb343db56c8226a720fbb1cdf467166c",
    "https://bcr.bazel.build/modules/rules_python/0.40.0/MODULE.bazel": "9d1a3cd88ed7d8e39583d9ffe56ae8a244f67783ae89b60caafc9f5cf318ada7",
-    "https://bcr.bazel.build/modules/rules_python/1.1.0/MODULE.bazel": "57e01abae22956eb96d891572490d20e07d983e0c065de0b2170cafe5053e788",
-    "https://bcr.bazel.build/modules/rules_python/1.1.0/source.json": "29f1fdfd23a40808c622f813bc93e29c3aae277333f03293f667e76159750a0f",
+    "https://bcr.bazel.build/modules/rules_python/1.3.0/MODULE.bazel": "8361d57eafb67c09b75bf4bbe6be360e1b8f4f18118ab48037f2bd50aa2ccb13",
+    "https://bcr.bazel.build/modules/rules_python/1.3.0/source.json": "25932f917cd279c7baefa6cb1d3fa8750a7a29de522024449b19af6eab51f4a0",
    "https://bcr.bazel.build/modules/rules_shell/0.2.0/MODULE.bazel": "fda8a652ab3c7d8fee214de05e7a9916d8b28082234e8d2c0094505c5268ed3c",
    "https://bcr.bazel.build/modules/rules_shell/0.2.0/source.json": "7f27af3c28037d9701487c4744b5448d26537cc66cdef0d8df7ae85411f8de95",
    "https://bcr.bazel.build/modules/stardoc/0.5.1/MODULE.bazel": "1a05d92974d0c122f5ccf09291442580317cdd859f07a8655f1db9a60374f9f8",
@ -134,53 +140,15 @@
    "https://bcr.bazel.build/modules/stardoc/0.7.2/source.json": "58b029e5e901d6802967754adf0a9056747e8176f017cfe3607c0851f4d42216",
    "https://bcr.bazel.build/modules/upb/0.0.0-20220923-a547704/MODULE.bazel": "7298990c00040a0e2f121f6c32544bab27d4452f80d9ce51349b1a28f3005c43",
    "https://bcr.bazel.build/modules/zlib/1.2.11/MODULE.bazel": "07b389abc85fdbca459b69e2ec656ae5622873af3f845e1c9d80fe179f3effa0",
-    "https://bcr.bazel.build/modules/zlib/1.3.1.bcr.3/MODULE.bazel": "af322bc08976524477c79d1e45e241b6efbeb918c497e8840b8ab116802dda79",
-    "https://bcr.bazel.build/modules/zlib/1.3.1.bcr.3/source.json": "2be409ac3c7601245958cd4fcdff4288be79ed23bd690b4b951f500d54ee6e7d",
+    "https://bcr.bazel.build/modules/zlib/1.3.1.bcr.5/MODULE.bazel": "eec517b5bbe5492629466e11dae908d043364302283de25581e3eb944326c4ca",
+    "https://bcr.bazel.build/modules/zlib/1.3.1.bcr.5/source.json": "22bc55c47af97246cfc093d0acf683a7869377de362b5d1c552c2c2e16b7a806",
    "https://bcr.bazel.build/modules/zlib/1.3.1/MODULE.bazel": "751c9940dcfe869f5f7274e1295422a34623555916eb98c174c1e945594bf198"
  },
  "selectedYankedVersions": {},
  "moduleExtensions": {
-    "@@platforms//host:extension.bzl%host_platform": {
-      "general": {
-        "bzlTransitiveDigest": "xelQcPZH8+tmuOHVjL9vDxMnnQNMlwj0SlvgoqBkm4U=",
-        "usagesDigest": "SeQiIN/f8/Qt9vYQk7qcXp4I4wJeEC0RnQDiaaJ4tb8=",
-        "recordedFileInputs": {},
-        "recordedDirentsInputs": {},
-        "envVariables": {},
-        "generatedRepoSpecs": {
-          "host_platform": {
-            "repoRuleId": "@@platforms//host:extension.bzl%host_platform_repo",
-            "attributes": {}
-          }
-        },
-        "recordedRepoMappingEntries": []
-      }
-    },
-    "@@rules_java+//java:rules_java_deps.bzl%compatibility_proxy": {
-      "general": {
-        "bzlTransitiveDigest": "84xJEZ1jnXXwo8BXMprvBm++rRt4jsTu9liBxz0ivps=",
-        "usagesDigest": "jTQDdLDxsS43zuRmg1faAjIEPWdLAbDAowI1pInQSoo=",
-        "recordedFileInputs": {},
-        "recordedDirentsInputs": {},
-        "envVariables": {},
-        "generatedRepoSpecs": {
-          "compatibility_proxy": {
-            "repoRuleId": "@@rules_java+//java:rules_java_deps.bzl%_compatibility_proxy_repo_rule",
-            "attributes": {}
-          }
-        },
-        "recordedRepoMappingEntries": [
-          [
-            "rules_java+",
-            "bazel_tools",
-            "bazel_tools"
-          ]
-        ]
-      }
-    },
    "@@rules_kotlin+//src/main/starlark/core/repositories:bzlmod_setup.bzl%rules_kotlin_extensions": {
      "general": {
-        "bzlTransitiveDigest": "sFhcgPbDQehmbD1EOXzX4H1q/CD5df8zwG4kp4jbvr8=",
+        "bzlTransitiveDigest": "hUTp2w+RUVdL7ma5esCXZJAFnX7vLbVfLd7FwnQI6bU=",
        "usagesDigest": "QI2z8ZUR+mqtbwsf2fLqYdJAkPOHdOV+tF2yVAUgRzw=",
        "recordedFileInputs": {},
        "recordedDirentsInputs": {},
@ -241,6 +209,42 @@
          ]
        ]
      }
+    },
+    "@@rules_python+//python/uv:uv.bzl%uv": {
+      "general": {
+        "bzlTransitiveDigest": "Xpqjnjzy6zZ90Es9Wa888ZLHhn7IsNGbph/e6qoxzw8=",
+        "usagesDigest": "vJ5RHUxAnV24M5swNGiAnkdxMx3Hp/iOLmNANTC5Xc8=",
+        "recordedFileInputs": {},
+        "recordedDirentsInputs": {},
+        "envVariables": {},
+        "generatedRepoSpecs": {
+          "uv": {
+            "repoRuleId": "@@rules_python+//python/uv/private:uv_toolchains_repo.bzl%uv_toolchains_repo",
+            "attributes": {
+              "toolchain_type": "'@@rules_python+//python/uv:uv_toolchain_type'",
+              "toolchain_names": [
+                "none"
+              ],
+              "toolchain_implementations": {
+                "none": "'@@rules_python+//python:none'"
+              },
+              "toolchain_compatible_with": {
+                "none": [
+                  "@platforms//:incompatible"
+                ]
+              },
+              "toolchain_target_settings": {}
+            }
+          }
+        },
+        "recordedRepoMappingEntries": [
+          [
+            "rules_python+",
+            "platforms",
+            "platforms"
+          ]
+        ]
+      }
    }
  }
 }
--- a/asl/BUILD.bazel
+++ b/asl/BUILD.bazel
@ -0,0 +1,17 @@
+# Copyright 2025 Steven Le Rouzic
+#
+# SPDX-License-Identifier: BSD-3-Clause
+
+config_setting(
+    name = "debug",
+    values = {
+        "compilation_mode": "dbg",
+    },
+)
+
+config_setting(
+    name = "optimized",
+    values = {
+        "compilation_mode": "opt",
+    },
+)
--- a/asl/base/BUILD.bazel
+++ b/asl/base/BUILD.bazel
@ -11,17 +11,26 @@ cc_library(
    hdrs = [
        "annotations.hpp",
        "assert.hpp",
+        "bit.hpp",
        "config.hpp",
        "defer.hpp",
        "float.hpp",
        "functional.hpp",
        "integers.hpp",
        "meta.hpp",
+        "numeric.hpp",
        "utility.hpp",
    ],
    srcs = [
        "assert.cpp",
    ],
+    defines = select({
+        "//asl:debug": ["ASL_DEBUG=1"],
+        "//conditions:default": ["ASL_DEBUG=0"],
+    }) + select({
+        "//asl:optimized": ["ASL_OPTIMIZED=1"],
+        "//conditions:default": ["ASL_OPTIMIZED=0"],
+    }),
    visibility = ["//visibility:public"],
 )

@ -37,10 +46,12 @@ cc_library(
        "//asl/types:box",
    ],
 ) for name in [
+    "bit",
    "defer",
    "float",
    "functional",
    "integers",
    "meta",
+    "numeric",
    "utility",
 ]]
--- a/asl/base/assert.cpp
+++ b/asl/base/assert.cpp
@ -4,7 +4,12 @@

 #include "asl/base/assert.hpp"

+#include "asl/base/meta.hpp"
+
+// NOLINTNEXTLINE(*-non-const-global-variables)
 static asl::AssertFailureHandler* s_handler = nullptr;
+
+// NOLINTNEXTLINE(*-non-const-global-variables)
 static void* s_user = nullptr;

 void asl::set_assert_failure_handler(AssertFailureHandler handler, void* user)
--- a/asl/base/assert.hpp
+++ b/asl/base/assert.hpp
@ -24,15 +24,17 @@ void report_assert_failure(const char* msg, const source_location& sl = source_l
    #define ASL_DEBUG_BREAK() __builtin_debugtrap()
 #endif

-// @Todo Configure asserts at build time
-
-#define ASL_ASSERT(...)                                                 \
-    if (__VA_ARGS__) {}                                                 \
-    else                                                                \
-    {                                                                   \
-        ::asl::report_assert_failure(#__VA_ARGS__);                     \
-        ASL_DEBUG_BREAK();                                              \
-    }
+#if !ASL_OPTIMIZED
+    #define ASL_ASSERT(...)                                                 \
+        if (__VA_ARGS__) {}                                                 \
+        else                                                                \
+        {                                                                   \
+            ::asl::report_assert_failure(#__VA_ARGS__);                     \
+            ASL_DEBUG_BREAK();                                              \
+        }
+#else
+    #define ASL_ASSERT(...)
+#endif

 #define ASL_ASSERT_RELEASE(...)                                         \
    if (__VA_ARGS__) {}                                                 \
--- a/asl/base/bit.hpp
+++ b/asl/base/bit.hpp
@ -0,0 +1,166 @@
+// Copyright 2025 Steven Le Rouzic
+//
+// SPDX-License-Identifier: BSD-3-Clause
+
+#pragma once
+
+#include "asl/base/integers.hpp"
+#include "asl/base/meta.hpp"
+
+namespace asl
+{
+
+constexpr bool has_single_bit(is_unsigned_integer auto x)
+{
+    return x != 0 && ((x - 1) & x) == 0;
+}
+
+constexpr int popcount(uint8_t v)
+{
+    v = v - ((v >> 1) & 0x55);
+    v = (v & 0x33) + ((v >> 2) & 0x33);
+    return (v + (v >> 4)) & 0x0F;
+}
+
+constexpr int popcount(uint16_t v)
+{
+    v = v - ((v >> 1) & 0x5555);
+    v = (v & 0x3333) + ((v >> 2) & 0x3333);
+    return static_cast<uint16_t>((v + (v >> 4) & 0x0F0F) * uint16_t{0x0101}) >> 8;
+}
+
+constexpr int popcount(uint32_t v)
+{
+    v = v - ((v >> 1) & 0x5555'5555);
+    v = (v & 0x3333'3333) + ((v >> 2) & 0x3333'3333);
+    return static_cast<int>(((v + (v >> 4) & 0x0F0F'0F0F) * 0x0101'0101) >> 24);
+}
+
+constexpr int popcount(uint64_t v)
+{
+    v = v - ((v >> 1) & 0x5555'5555'5555'5555);
+    v = (v & 0x3333'3333'3333'3333) + ((v >> 2) & 0x3333'3333'3333'3333);
+    return static_cast<int>(((v + (v >> 4) & 0x0F0F'0F0F'0F0F'0F0F) * 0x0101'0101'0101'0101) >> 56);
+}
+
+constexpr uint8_t propagate_right_one(uint8_t v)
+{
+    v = v | (v >> 1);
+    v = v | (v >> 2);
+    v = v | (v >> 4);
+    return v;
+}
+
+constexpr uint16_t propagate_right_one(uint16_t v)
+{
+    v = v | (v >> 1);
+    v = v | (v >> 2);
+    v = v | (v >> 4);
+    v = v | (v >> 8);
+    return v;
+}
+
+constexpr uint32_t propagate_right_one(uint32_t v)
+{
+    v = v | (v >> 1);
+    v = v | (v >> 2);
+    v = v | (v >> 4);
+    v = v | (v >> 8);
+    v = v | (v >> 16);
+    return v;
+}
+
+constexpr uint64_t propagate_right_one(uint64_t v)
+{
+    v = v | (v >> 1);
+    v = v | (v >> 2);
+    v = v | (v >> 4);
+    v = v | (v >> 8);
+    v = v | (v >> 16);
+    v = v | (v >> 32);
+    return v;
+}
+
+constexpr int countr_zero(is_unsigned_integer auto v)
+{
+    v = ~v & (v - 1);
+    return popcount(v);
+}
+
+constexpr int countr_one(is_unsigned_integer auto v)
+{
+    v = v & (~v - 1);
+    return popcount(v);
+}
+
+constexpr int countl_zero(is_unsigned_integer auto v)
+{
+    v = ~propagate_right_one(v);
+    return popcount(v);
+}
+
+constexpr int countl_one(is_unsigned_integer auto v)
+{
+    v = ~v;
+    v = ~propagate_right_one(v);
+    return popcount(v);
+}
+
+template<is_unsigned_integer T>
+constexpr T rotr(T v, int s);
+
+template<is_unsigned_integer T>
+constexpr T rotl(T v, int s) // NOLINT(*-no-recursion)
+{
+    static constexpr int N = sizeof(decltype(v)) * 8;
+    s = s % N;
+    return (s >= 0) ? (v << s) | (v >> ((N - s) % N)) : rotr(v, -s);
+}
+
+template<is_unsigned_integer T>
+constexpr T rotr(T v, int s) // NOLINT(*-no-recursion)
+{
+    static constexpr int N = sizeof(decltype(v)) * 8;
+    s = s % N;
+    return (s >= 0) ? (v >> s) | (v << ((N - s) % N)) : rotl(v, -s);
+}
+
+constexpr uint16_t byteswap(uint16_t v)
+{
+    return static_cast<uint16_t>((v << 8U) | (v >> 8U));
+}
+
+constexpr uint32_t byteswap(uint32_t v)
+{
+    return rotr(v & 0x00ff'00ff, 8) | rotl(v & 0xff00'ff00, 8);
+}
+
+constexpr uint64_t byteswap(uint64_t v)
+{
+    return (uint64_t{byteswap(static_cast<uint32_t>(v))} << 32)
+        | uint64_t{byteswap(static_cast<uint32_t>(v >> 32))};
+}
+
+constexpr auto bit_ceil(is_unsigned_integer auto v)
+{
+    v -= 1;
+    v = propagate_right_one(v);
+    v += 1;
+    return v;
+}
+
+constexpr auto bit_floor(is_unsigned_integer auto v)
+{
+    v = propagate_right_one(v);
+    v = v - (v >> 1);
+    return v;
+}
+
+constexpr int bit_width(is_unsigned_integer auto v)
+{
+    static constexpr int N = sizeof(decltype(v)) * 8;
+    return N - countl_zero(v);
+}
+
+} // namespace asl
+
--- a/asl/base/bit_tests.cpp
+++ b/asl/base/bit_tests.cpp
@ -0,0 +1,198 @@
+// Copyright 2025 Steven Le Rouzic
+//
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include "asl/base/bit.hpp"
+
+#include "asl/testing/testing.hpp"
+
+ASL_TEST(has_single_bit)
+{
+    ASL_TEST_EXPECT(asl::has_single_bit(4U));
+    ASL_TEST_EXPECT(asl::has_single_bit(1024U));
+    ASL_TEST_EXPECT(asl::has_single_bit(0x8000'0000U));
+    ASL_TEST_EXPECT(asl::has_single_bit(uint64_t{0x0000'8000'0000'0000ULL}));
+    ASL_TEST_EXPECT(!asl::has_single_bit(0U));
+    ASL_TEST_EXPECT(!asl::has_single_bit(3U));
+    ASL_TEST_EXPECT(!asl::has_single_bit(341U));
+}
+
+ASL_TEST(popcount) // NOLINT(*-cognitive-complexity)
+{
+    ASL_TEST_EXPECT(asl::popcount(uint8_t{0}) == 0);
+    ASL_TEST_EXPECT(asl::popcount(uint8_t{255}) == 8);
+    ASL_TEST_EXPECT(asl::popcount(uint8_t{46}) == 4);
+    ASL_TEST_EXPECT(asl::popcount(uint16_t{0}) == 0);
+    ASL_TEST_EXPECT(asl::popcount(uint16_t{255}) == 8);
+    ASL_TEST_EXPECT(asl::popcount(uint16_t{65535}) == 16);
+    ASL_TEST_EXPECT(asl::popcount(uint16_t{46}) == 4);
+    ASL_TEST_EXPECT(asl::popcount(uint32_t{0}) == 0);
+    ASL_TEST_EXPECT(asl::popcount(uint32_t{255}) == 8);
+    ASL_TEST_EXPECT(asl::popcount(uint32_t{65535}) == 16);
+    ASL_TEST_EXPECT(asl::popcount(uint32_t{65536}) == 1);
+    ASL_TEST_EXPECT(asl::popcount(uint32_t{46}) == 4);
+    ASL_TEST_EXPECT(asl::popcount(uint32_t{0xffff'ffff}) == 32);
+    ASL_TEST_EXPECT(asl::popcount(0x8421'1248'8421'1248) == 16);
+    ASL_TEST_EXPECT(asl::popcount(0xffff'ffff'ffff'ffff) == 64);
+}
+
+ASL_TEST(countr_zero)
+{
+    ASL_TEST_EXPECT(asl::countr_zero(uint8_t{0}) == 8);
+    ASL_TEST_EXPECT(asl::countr_zero(uint8_t{1}) == 0);
+    ASL_TEST_EXPECT(asl::countr_zero(uint8_t{2}) == 1);
+    ASL_TEST_EXPECT(asl::countr_zero(uint8_t{4}) == 2);
+    ASL_TEST_EXPECT(asl::countr_zero(uint8_t{8}) == 3);
+    ASL_TEST_EXPECT(asl::countr_zero(uint8_t{255}) == 0);
+    ASL_TEST_EXPECT(asl::countr_zero(uint8_t{0b00011100}) == 2);
+    ASL_TEST_EXPECT(asl::countr_zero(uint8_t{0b10101010}) == 1);
+    ASL_TEST_EXPECT(asl::countr_zero(uint8_t{0b10101001}) == 0);
+}
+
+ASL_TEST(countr_one)
+{
+    ASL_TEST_EXPECT(asl::countr_one(uint8_t{0}) == 0);
+    ASL_TEST_EXPECT(asl::countr_one(uint8_t{255}) == 8);
+    ASL_TEST_EXPECT(asl::countr_one(uint8_t{0b00011100}) == 0);
+    ASL_TEST_EXPECT(asl::countr_one(uint8_t{0b10101011}) == 2);
+    ASL_TEST_EXPECT(asl::countr_one(uint8_t{0b10101001}) == 1);
+}
+
+ASL_TEST(countl_zero)
+{
+    ASL_TEST_EXPECT(asl::countl_zero(uint8_t{0}) == 8);
+    ASL_TEST_EXPECT(asl::countl_zero(uint8_t{255}) == 0);
+    ASL_TEST_EXPECT(asl::countl_zero(uint8_t{0b00011100}) == 3);
+    ASL_TEST_EXPECT(asl::countl_zero(uint8_t{0b10101010}) == 0);
+    ASL_TEST_EXPECT(asl::countl_zero(uint8_t{0b00001001}) == 4);
+}
+
+ASL_TEST(countl_one)
+{
+    ASL_TEST_EXPECT(asl::countl_one(uint8_t{0}) == 0);
+    ASL_TEST_EXPECT(asl::countl_one(uint8_t{255}) == 8);
+    ASL_TEST_EXPECT(asl::countl_one(uint8_t{0b00011100}) == 0);
+    ASL_TEST_EXPECT(asl::countl_one(uint8_t{0b10101010}) == 1);
+    ASL_TEST_EXPECT(asl::countl_one(uint8_t{0b11101001}) == 3);
+}
+
+ASL_TEST(rotl)
+{
+    ASL_TEST_EXPECT(asl::rotl(uint32_t{0x4000'0100}, 1) == 0x8000'0200);
+    ASL_TEST_EXPECT(asl::rotl(uint32_t{0x4000'0100}, 3) == 0x0000'0802);
+    ASL_TEST_EXPECT(asl::rotl(uint32_t{0x4000'0100}, 0) == 0x4000'0100);
+    ASL_TEST_EXPECT(asl::rotl(uint32_t{0x4000'0100}, -1) == 0x2000'0080);
+    ASL_TEST_EXPECT(asl::rotl(uint32_t{0x4000'0100}, -12) == 0x1004'0000);
+}
+
+ASL_TEST(rotr)
+{
+    ASL_TEST_EXPECT(asl::rotr(uint32_t{0x4000'0100}, -1) == 0x8000'0200);
+    ASL_TEST_EXPECT(asl::rotr(uint32_t{0x4000'0100}, -3) == 0x0000'0802);
+    ASL_TEST_EXPECT(asl::rotr(uint32_t{0x4000'0100}, 0) == 0x4000'0100);
+    ASL_TEST_EXPECT(asl::rotr(uint32_t{0x4000'0100}, 1) == 0x2000'0080);
+    ASL_TEST_EXPECT(asl::rotr(uint32_t{0x4000'0100}, 12) == 0x1004'0000);
+}
+
+ASL_TEST(byteswap)
+{
+    ASL_TEST_EXPECT(asl::byteswap(uint32_t{0x1234'5678}) == 0x7856'3412);
+    ASL_TEST_EXPECT(asl::byteswap(uint16_t{0x1234}) == 0x3412);
+    ASL_TEST_EXPECT(asl::byteswap(uint64_t{0x0123'4567'89ab'cdef}) == 0xefcd'ab89'6745'2301);
+}
+
+ASL_TEST(bit_ceil) // NOLINT(*-cognitive-complexity)
+{
+    ASL_TEST_EXPECT(asl::bit_ceil(uint8_t{0}) == 0);
+    ASL_TEST_EXPECT(asl::bit_ceil(uint8_t{1}) == 1);
+    ASL_TEST_EXPECT(asl::bit_ceil(uint8_t{2}) == 2);
+    ASL_TEST_EXPECT(asl::bit_ceil(uint8_t{3}) == 4);
+    ASL_TEST_EXPECT(asl::bit_ceil(uint8_t{4}) == 4);
+    ASL_TEST_EXPECT(asl::bit_ceil(uint8_t{5}) == 8);
+    ASL_TEST_EXPECT(asl::bit_ceil(uint8_t{6}) == 8);
+    ASL_TEST_EXPECT(asl::bit_ceil(uint8_t{127}) == 128);
+    ASL_TEST_EXPECT(asl::bit_ceil(uint8_t{128}) == 128);
+    ASL_TEST_EXPECT(asl::bit_ceil(uint8_t{254}) == 0);
+    ASL_TEST_EXPECT(asl::bit_ceil(uint8_t{255}) == 0);
+
+    ASL_TEST_EXPECT(asl::bit_ceil(uint16_t{0}) == 0);
+    ASL_TEST_EXPECT(asl::bit_ceil(uint16_t{1}) == 1);
+    ASL_TEST_EXPECT(asl::bit_ceil(uint16_t{2}) == 2);
+    ASL_TEST_EXPECT(asl::bit_ceil(uint16_t{3}) == 4);
+    ASL_TEST_EXPECT(asl::bit_ceil(uint16_t{4}) == 4);
+    ASL_TEST_EXPECT(asl::bit_ceil(uint16_t{5}) == 8);
+    ASL_TEST_EXPECT(asl::bit_ceil(uint16_t{6}) == 8);
+    ASL_TEST_EXPECT(asl::bit_ceil(uint16_t{32000}) == 32768);
+    ASL_TEST_EXPECT(asl::bit_ceil(uint16_t{32768}) == 32768);
+    ASL_TEST_EXPECT(asl::bit_ceil(uint16_t{35000}) == 0);
+    ASL_TEST_EXPECT(asl::bit_ceil(uint16_t{65535}) == 0);
+}
+
+ASL_TEST(bit_floor) // NOLINT(*-cognitive-complexity)
+{
+    ASL_TEST_EXPECT(asl::bit_floor(uint8_t{0}) == 0);
+    ASL_TEST_EXPECT(asl::bit_floor(uint8_t{1}) == 1);
+    ASL_TEST_EXPECT(asl::bit_floor(uint8_t{2}) == 2);
+    ASL_TEST_EXPECT(asl::bit_floor(uint8_t{3}) == 2);
+    ASL_TEST_EXPECT(asl::bit_floor(uint8_t{4}) == 4);
+    ASL_TEST_EXPECT(asl::bit_floor(uint8_t{5}) == 4);
+    ASL_TEST_EXPECT(asl::bit_floor(uint8_t{6}) == 4);
+    ASL_TEST_EXPECT(asl::bit_floor(uint8_t{127}) == 64);
+    ASL_TEST_EXPECT(asl::bit_floor(uint8_t{128}) == 128);
+    ASL_TEST_EXPECT(asl::bit_floor(uint8_t{254}) == 128);
+    ASL_TEST_EXPECT(asl::bit_floor(uint8_t{255}) == 128);
+
+    ASL_TEST_EXPECT(asl::bit_floor(uint16_t{0}) == 0);
+    ASL_TEST_EXPECT(asl::bit_floor(uint16_t{1}) == 1);
+    ASL_TEST_EXPECT(asl::bit_floor(uint16_t{2}) == 2);
+    ASL_TEST_EXPECT(asl::bit_floor(uint16_t{3}) == 2);
+    ASL_TEST_EXPECT(asl::bit_floor(uint16_t{4}) == 4);
+    ASL_TEST_EXPECT(asl::bit_floor(uint16_t{5}) == 4);
+    ASL_TEST_EXPECT(asl::bit_floor(uint16_t{6}) == 4);
+    ASL_TEST_EXPECT(asl::bit_floor(uint16_t{32000}) == 16384);
+    ASL_TEST_EXPECT(asl::bit_floor(uint16_t{32768}) == 32768);
+    ASL_TEST_EXPECT(asl::bit_floor(uint16_t{35000}) == 32768);
+    ASL_TEST_EXPECT(asl::bit_floor(uint16_t{65535}) == 32768);
+}
+
+ASL_TEST(bit_width) // NOLINT(*-cognitive-complexity)
+{
+    ASL_TEST_EXPECT(asl::bit_width(uint8_t{0}) == 0);
+    ASL_TEST_EXPECT(asl::bit_width(uint8_t{1}) == 1);
+    ASL_TEST_EXPECT(asl::bit_width(uint8_t{2}) == 2);
+    ASL_TEST_EXPECT(asl::bit_width(uint8_t{3}) == 2);
+    ASL_TEST_EXPECT(asl::bit_width(uint8_t{4}) == 3);
+    ASL_TEST_EXPECT(asl::bit_width(uint8_t{5}) == 3);
+    ASL_TEST_EXPECT(asl::bit_width(uint8_t{6}) == 3);
+
+    ASL_TEST_EXPECT(asl::bit_width(uint16_t{0}) == 0);
+    ASL_TEST_EXPECT(asl::bit_width(uint16_t{1}) == 1);
+    ASL_TEST_EXPECT(asl::bit_width(uint16_t{2}) == 2);
+    ASL_TEST_EXPECT(asl::bit_width(uint16_t{3}) == 2);
+    ASL_TEST_EXPECT(asl::bit_width(uint16_t{4}) == 3);
+    ASL_TEST_EXPECT(asl::bit_width(uint16_t{5}) == 3);
+    ASL_TEST_EXPECT(asl::bit_width(uint16_t{6}) == 3);
+    ASL_TEST_EXPECT(asl::bit_width(uint16_t{65535}) == 16);
+
+    ASL_TEST_EXPECT(asl::bit_width(uint32_t{0}) == 0);
+    ASL_TEST_EXPECT(asl::bit_width(uint32_t{1}) == 1);
+    ASL_TEST_EXPECT(asl::bit_width(uint32_t{2}) == 2);
+    ASL_TEST_EXPECT(asl::bit_width(uint32_t{3}) == 2);
+    ASL_TEST_EXPECT(asl::bit_width(uint32_t{4}) == 3);
+    ASL_TEST_EXPECT(asl::bit_width(uint32_t{5}) == 3);
+    ASL_TEST_EXPECT(asl::bit_width(uint32_t{6}) == 3);
+    ASL_TEST_EXPECT(asl::bit_width(uint32_t{65535}) == 16);
+    ASL_TEST_EXPECT(asl::bit_width(uint32_t{65536}) == 17);
+    ASL_TEST_EXPECT(asl::bit_width(uint32_t{0xffff'ffff}) == 32);
+
+    ASL_TEST_EXPECT(asl::bit_width(uint64_t{0}) == 0);
+    ASL_TEST_EXPECT(asl::bit_width(uint64_t{1}) == 1);
+    ASL_TEST_EXPECT(asl::bit_width(uint64_t{2}) == 2);
+    ASL_TEST_EXPECT(asl::bit_width(uint64_t{3}) == 2);
+    ASL_TEST_EXPECT(asl::bit_width(uint64_t{4}) == 3);
+    ASL_TEST_EXPECT(asl::bit_width(uint64_t{5}) == 3);
+    ASL_TEST_EXPECT(asl::bit_width(uint64_t{6}) == 3);
+    ASL_TEST_EXPECT(asl::bit_width(uint64_t{65535}) == 16);
+    ASL_TEST_EXPECT(asl::bit_width(uint64_t{65536}) == 17);
+    ASL_TEST_EXPECT(asl::bit_width(uint64_t{0xffff'ffff}) == 32);
+}
--- a/asl/base/config.hpp
+++ b/asl/base/config.hpp
@ -2,6 +2,8 @@
 //
 // SPDX-License-Identifier: BSD-3-Clause

+// NOLINTBEGIN(*-macro-to-enum)
+
 #pragma once

 #if defined(_WIN32)
@ -19,3 +21,16 @@
 #else
    #error Unknown compiler
 #endif
+
+// ASL_DEBUG=1 for slow builds, with extra validation logic and such.
+#if !defined(ASL_DEBUG)
+    #error ASL_DEBUG should be defined to 0 or 1
+#endif
+
+// ASL_OPTIMIZED=1 for fast builds, with minimal validation logic.
+#if !defined(ASL_OPTIMIZED)
+    #error ASL_OPTIMIZED should be defined to 0 or 1
+#endif
+
+// NOLINTEND(*-macro-to-enum)
+
--- a/asl/base/defer.hpp
+++ b/asl/base/defer.hpp
@ -18,14 +18,16 @@ class DeferCallback

 public:
    template<typename T>
-    explicit DeferCallback(T&& callback) : m_callback(ASL_FWD(callback))
+    explicit DeferCallback(T&& callback)
+        requires (!same_as<un_cvref_t<T>, DeferCallback>)
+        : m_callback(std::forward<T>(callback))
    {
    }

    ASL_DELETE_COPY(DeferCallback);

    DeferCallback(DeferCallback&& other) :
-        m_callback(ASL_MOVE(other.m_callback)), m_moved(exchange(other.m_moved, true))
+        m_callback(std::move(other.m_callback)), m_moved(exchange(other.m_moved, true))
    {
    }

@ -42,7 +44,7 @@ struct DeferFactory
    template<invocable Callback>
    DeferCallback<Callback> operator<<(Callback&& callback) const
    {
-        return DeferCallback<Callback>(ASL_FWD(callback));
+        return DeferCallback<Callback>(std::forward<Callback>(callback));
    }
 };

--- a/asl/base/defer_tests.cpp
+++ b/asl/base/defer_tests.cpp
@ -10,25 +10,25 @@ ASL_TEST(defer)
    uint32_t a = 0;

    {
-        ASL_DEFER [&a]() { a |= 1; };
+        ASL_DEFER [&a]() { a |= 1U; };
        ASL_TEST_EXPECT(a == 0);

        {
-            ASL_DEFER [&a]() { a |= 2; };
-            ASL_DEFER [&a]() { a |= 4; };
+            ASL_DEFER [&a]() { a |= 2U; };
+            ASL_DEFER [&a]() { a |= 4U; };
            ASL_TEST_EXPECT(a == 0);
        }

        ASL_TEST_EXPECT(a == 6);

        {
-            ASL_DEFER [&a]() { a |= 8; };
+            ASL_DEFER [&a]() { a |= 8U; };
            ASL_TEST_EXPECT(a == 6);
        }

        ASL_TEST_EXPECT(a == 14);

-        ASL_DEFER [&a]() { a |= 16; };
+        ASL_DEFER [&a]() { a |= 16U; };
        ASL_TEST_EXPECT(a == 14);
    }

--- a/asl/base/float.hpp
+++ b/asl/base/float.hpp
@ -6,12 +6,42 @@

 #include "asl/base/meta.hpp"

+using float32_t = float;
+using float64_t = double;
+
 namespace asl
 {

-template<is_floating_point T> constexpr T infinity() { return __builtin_inf(); }
+template<typename T> struct float_traits {};

-template<is_floating_point T> constexpr T nan() { return static_cast<T>(__builtin_nanf("")); }
+#define ASL_FLOAT_TRAITS(T, INF, NAN, EPS, SMALLEST) \
+    template<> struct float_traits<T> \
+    { \
+        static constexpr T kInfinity{__builtin_bit_cast(T, INF)}; \
+        static constexpr T kNaN{__builtin_bit_cast(T, NAN)}; \
+        static constexpr T kEpsilon{EPS}; \
+        static constexpr T kSmallest{__builtin_bit_cast(T, SMALLEST)}; \
+    };
+
+ASL_FLOAT_TRAITS(
+    float32_t,
+    0x7F800000,
+    0x7FC00000,
+    __builtin_bit_cast(float32_t, 0x3F800001) - float32_t{1},
+    0x00800000
+);
+
+ASL_FLOAT_TRAITS(
+    float64_t,
+    0x7FF0000000000000,
+    0x7FF8000000000000,
+    __builtin_bit_cast(float64_t, 0x3FF0000000000001) - float64_t{1},
+    0x0010000000000000
+);
+
+template<is_floating_point T> constexpr T infinity() { return float_traits<T>::kInfinity; }
+
+template<is_floating_point T> constexpr T nan() { return float_traits<T>::kNaN; }

 template<is_floating_point T> constexpr bool is_infinity(T f) { return __builtin_isinf(f); }

--- a/asl/base/functional.hpp
+++ b/asl/base/functional.hpp
@ -9,56 +9,62 @@

 namespace asl {

-template<typename... Args, typename C>
+template<typename F, typename... Args>
+constexpr auto invoke(F&& f, Args&&... args)
+    -> decltype(std::forward<F>(f)(std::forward<Args>(args)...))
+    requires (!is_member_ptr<un_cvref_t<F>>) && requires {
+        f(std::forward<Args>(args)...);
+    }
+{
+    return std::forward<F>(f)(std::forward<Args>(args)...);
+}
+
+template<typename C>
+constexpr auto&& invoke(auto C::* f, same_or_derived_from<C> auto&& arg)
+{
+    return std::forward<decltype(arg)>(arg).*f;
+}
+
+template<typename C>
+constexpr auto&& invoke(auto C::* f, auto&& arg)
+    requires (
+        !same_or_derived_from<decltype(arg), C>
+        && requires { (*arg).*f; }
+    )
+{
+    return (*std::forward<decltype(arg)>(arg)).*f;
+}
+
+template<typename C, typename... Args>
+constexpr auto invoke(is_func auto C::* f, same_or_derived_from<C> auto&& self, Args&&... args)
+    -> decltype((std::forward<decltype(self)>(self).*f)(std::forward<Args>(args)...))
+    requires requires { (self.*f)(std::forward<Args>(args)...); }
+{
+    return (std::forward<decltype(self)>(self).*f)(std::forward<Args>(args)...);
+}
+
+template<typename C, typename... Args>
 constexpr auto invoke(is_func auto C::* f, auto&& self, Args&&... args)
-    -> decltype((self.*f)(ASL_FWD(args)...))
-    requires requires {
-        (self.*f)(ASL_FWD(args)...);
-    }
-{
-    return (ASL_FWD(self).*f)(ASL_FWD(args)...);
-}
-
-template<typename... Args, typename C>
-constexpr auto invoke(is_func auto C::* f, auto* self, Args&&... args)
-    -> decltype((self->*f)(ASL_FWD(args)...))
-    requires requires {
-        (self->*f)(ASL_FWD(args)...);
-    }
-{
-    return (self->*f)(ASL_FWD(args)...);
-}
-
-template<typename... Args, typename C>
-constexpr auto invoke(is_object auto C::* m, auto&& self, Args&&...)
-    -> decltype(self.*m)
+    -> decltype(((*std::forward<decltype(self)>(self)).*f)(std::forward<Args>(args)...))
    requires (
-        sizeof...(Args) == 0 &&
-        requires { self.*m; }
+        !same_or_derived_from<decltype(self), C>
+        && requires { ((*self).*f)(std::forward<Args>(args)...); }
    )
 {
-    return ASL_FWD(self).*m;
+    return ((*std::forward<decltype(self)>(self)).*f)(std::forward<Args>(args)...);
 }

-template<typename... Args, typename C>
-constexpr auto invoke(is_object auto C::* m, auto* self, Args&&...)
-    -> decltype(self->*m)
-    requires (
-        sizeof...(Args) == 0 &&
-        requires { self->*m; }
-    )
+template<typename R, typename F, typename... Args>
+constexpr R invoke_r(F&& f, Args&&... args)
 {
-    return self->*m;
-}
-
-template<typename... Args>
-constexpr auto invoke(auto&& f, Args&&... args)
-    -> decltype(f(ASL_FWD(args)...))
-    requires requires {
-        f(ASL_FWD(args)...);
+    if constexpr (is_void<R>)
+    {
+        static_cast<void>(invoke(std::forward<F>(f), std::forward<Args>(args)...));
+    }
+    else
+    {
+        return invoke(std::forward<F>(f), std::forward<Args>(args)...);
    }
-{
-    return ASL_FWD(f)(ASL_FWD(args)...);
 }

 template<typename Void, typename F, typename... Args>
@ -76,7 +82,11 @@ using invoke_result_t = _invoke_result_helper<void, F, Args...>::type;
 template<typename F, typename... Args>
 concept invocable = requires (F&& f, Args&&... args)
 {
-    invoke(ASL_FWD(f), ASL_FWD(args)...);
+    invoke(std::forward<F>(f), std::forward<Args>(args)...);
 };

+template<typename R, typename F, typename... Args>
+concept invocable_r = invocable<F, Args...>
+    && (is_void<R> || convertible_to<invoke_result_t<F, Args...>, R>);
+
 } // namespace asl
--- a/asl/base/functional_tests.cpp
+++ b/asl/base/functional_tests.cpp
@ -7,9 +7,12 @@

 struct HasFunction
 {
-    void do_something(int, float) {}
+    void do_something(int, float) const {}
+    int& do_something2(int, float) &;
 };

+struct HasFunction2 : public HasFunction {};
+
 struct HasMember
 {
    int member{};
@ -17,6 +20,8 @@ struct HasMember
    void (*member_fn)(){};
 };

+struct HasMember2 : public HasMember {};
+
 struct Functor
 {
    int64_t operator()() { return 35; }
@ -34,7 +39,13 @@ static_assert(asl::same_as<asl::invoke_result_t<Functor>, int64_t>);
 static_assert(asl::same_as<asl::invoke_result_t<Functor, int>, int>);
 static_assert(asl::same_as<asl::invoke_result_t<decltype(static_cast<float(*)(float)>(some_func1)), float>, float>);
 static_assert(asl::same_as<asl::invoke_result_t<decltype(&HasFunction::do_something), HasFunction, int, float>, void>);
-static_assert(asl::same_as<asl::invoke_result_t<decltype(&HasMember::member), const HasMember>, const int&>);
+static_assert(asl::same_as<asl::invoke_result_t<decltype(&HasFunction::do_something), const HasFunction2&, int, float>, void>);
+static_assert(asl::same_as<asl::invoke_result_t<decltype(&HasFunction::do_something), HasFunction*, int, float>, void>);
+static_assert(asl::same_as<asl::invoke_result_t<decltype(&HasFunction::do_something2), HasFunction2&, int, float>, int&>);
+static_assert(asl::same_as<asl::invoke_result_t<decltype(&HasFunction::do_something2), HasFunction*, int, float>, int&>);
+static_assert(asl::same_as<asl::invoke_result_t<decltype(&HasMember::member), HasMember>, int&&>);
+static_assert(asl::same_as<asl::invoke_result_t<decltype(&HasMember::member), const HasMember&>, const int&>);
+static_assert(asl::same_as<asl::invoke_result_t<decltype(&HasMember::member), const HasMember2*>, const int&>);

 static_assert(asl::invocable<int()>);
 static_assert(!asl::invocable<int(), int>);
@ -45,8 +56,20 @@ static_assert(asl::invocable<Functor, int>);
 static_assert(!asl::invocable<Functor, void*>);
 static_assert(asl::invocable<decltype(static_cast<float(*)(float)>(some_func1)), float>);
 static_assert(asl::invocable<decltype(&HasFunction::do_something), HasFunction, int, float>);
+static_assert(asl::invocable<decltype(&HasFunction::do_something), const HasFunction2&, int, float>);
+static_assert(asl::invocable<decltype(&HasFunction::do_something), HasFunction*, int, float>);
 static_assert(!asl::invocable<decltype(&HasFunction::do_something), HasFunction, int, int*>);
-static_assert(asl::invocable<decltype(&HasMember::member), const HasMember>);
+static_assert(!asl::invocable<decltype(&HasFunction::do_something2), HasFunction, int, float>);
+static_assert(!asl::invocable<decltype(&HasFunction::do_something2), const HasFunction2&, int, float>);
+static_assert(asl::invocable<decltype(&HasFunction::do_something2), HasFunction2&, int, float>);
+static_assert(asl::invocable<decltype(&HasFunction::do_something2), HasFunction*, int, float>);
+static_assert(!asl::invocable<decltype(&HasFunction::do_something2), HasFunction, int, int*>);
+static_assert(asl::invocable<decltype(&HasMember::member), const HasMember2>);
+static_assert(asl::invocable<decltype(&HasMember::member), const HasMember&>);
+static_assert(asl::invocable<decltype(&HasMember::member), const HasMember2*>);
+
+static_assert(asl::invocable_r<void*, int*()>);
+static_assert(!asl::invocable_r<int*, void*()>);

 ASL_TEST(invoke_member_function)
 {
@ -89,3 +112,9 @@ ASL_TEST(invoke_lambda)
    ASL_TEST_EXPECT(asl::invoke([](){ return 35; }) == 35);
    ASL_TEST_EXPECT(asl::invoke([](int x){ return x + 2; }, 6) == 8);
 }
+
+ASL_TEST(invoke_r)
+{
+    ASL_TEST_EXPECT(asl::invoke_r<int>([]() { return 1ULL; }) == 1);
+    asl::invoke_r<void>([]() { return 1ULL; });
+}
--- a/asl/base/integers.hpp
+++ b/asl/base/integers.hpp
@ -40,5 +40,25 @@ namespace asl

 enum class byte : uint8_t {};

+template<typename T> struct integer_traits {};
+
+#define ASL_INTEGER_TRAITS(T, MIN, MAX)               \
+    template<> struct integer_traits<T>               \
+    {                                                 \
+        static constexpr T kMin{static_cast<T>(MIN)}; \
+        static constexpr T kMax{static_cast<T>(MAX)}; \
+    }
+
+ASL_INTEGER_TRAITS(uint8_t,   0,                     0xff);
+ASL_INTEGER_TRAITS(uint16_t,  0,                     0xffff);
+ASL_INTEGER_TRAITS(uint32_t,  0,                     0xffff'ffff);
+ASL_INTEGER_TRAITS(uint64_t,  0,                     0xffff'ffff'ffff'ffff);
+ASL_INTEGER_TRAITS(int8_t,   -0x80,                  0x7f);
+ASL_INTEGER_TRAITS(int16_t,  -0x8000,                0x7fff);
+ASL_INTEGER_TRAITS(int32_t,  -0x8000'0000,           0x7fff'ffff);
+ASL_INTEGER_TRAITS(int64_t,  -0x8000'0000'0000'0000, 0x7fff'ffff'ffff'ffff);
+
+#undef ASL_INTEGER_TRAITS
+
 } // namespace asl

--- a/asl/base/meta.hpp
+++ b/asl/base/meta.hpp
@ -25,6 +25,9 @@ struct empty {};

 template<typename T> struct id { using type = T; };

+struct in_place_t {};
+static constexpr in_place_t in_place{};
+
 template<typename... Args> static constexpr isize_t types_count = sizeof...(Args);

 template<typename T, T kValue> struct integral_constant { static constexpr T value = kValue; };
@ -54,6 +57,11 @@ template<typename T> using as_rref_t = decltype(_as_rref_helper<T>(0))::type;

 template<typename T> consteval as_rref_t<T> declval() {}

+template<typename T> auto _as_ptr_helper(int) -> id<T*>;
+template<typename T> auto _as_ptr_helper(...) -> id<T>;
+
+template<typename T> using as_ptr_t = decltype(_as_ptr_helper<T>(0))::type;
+
 template<typename T> struct _un_ref_t      { using type = T; };
 template<typename T> struct _un_ref_t<T&>  { using type = T; };
 template<typename T> struct _un_ref_t<T&&> { using type = T; };
@ -87,12 +95,6 @@ template<typename T> concept trivially_destructible = __is_trivially_destructibl
 template<typename T> concept copyable = copy_constructible<T> && copy_assignable<T>;
 template<typename T> concept moveable = move_constructible<T> && move_assignable<T>;

-template<typename To, typename From>
-concept convertible_from = __is_convertible(From, To);
-
-template<typename Derived, class Base>
-concept derived_from = __is_class(Derived) && __is_class(Base) && convertible_from<const volatile Base*, const volatile Derived*>;
-
 using nullptr_t = decltype(nullptr);

 template<typename T> struct _un_const_helper          { using type = T; };
@ -144,16 +146,27 @@ struct _copy_const_helper<From, To, true> { using type = const To; };
 template<typename From, typename To> using copy_cref_t =
    _copy_ref_helper<From, typename _copy_const_helper<From, un_cvref_t<To>>::type>::type;

+template<typename From, typename To> using copy_const_t = _copy_const_helper<From, un_cvref_t<To>>::type;
+
 template<typename T> struct _is_ptr_helper     : false_type {};
 template<typename T> struct _is_ptr_helper<T*> : true_type {};

 template<typename T> concept is_ptr = _is_ptr_helper<un_cv_t<T>>::value;

+template<typename From, typename To>
+concept convertible_to = __is_convertible(From, To);
+
+template<typename Derived, typename Base>
+concept derived_from = __is_class(Derived) && __is_class(Base) && convertible_to<const volatile Derived*, const volatile Base*>;
+
+template<typename Derived, typename Base>
+concept same_or_derived_from = same_as<un_cvref_t<Derived>, Base> || derived_from<un_cvref_t<Derived>, Base>;
+
 template<typename T> struct _tame_helper { using type = T; };

 #define TAME_HELPER_IMPL(TRAILING)                                  \
    template<typename R, typename... Args>                          \
-    struct _tame_helper<R(Args...) TRAILING> { using type = R(Args...); }
+    struct _tame_helper<R(Args...) TRAILING> { using type = R(Args...); } // NOLINT(*-parentheses)

 TAME_HELPER_IMPL();
 TAME_HELPER_IMPL(&);
@ -189,13 +202,36 @@ template<typename R, typename... Args> struct _is_func_helper<R(Args...)> : true

 template<typename T> concept is_func = _is_func_helper<tame_t<T>>::value;

+template<typename T>             struct _is_member_ptr_helper         : false_type {};
+template<typename C, typename T> struct _is_member_ptr_helper<T C::*> : true_type
+{
+    static constexpr bool kIsFunc = is_func<T>;
+};
+
+template<typename T> concept is_member_ptr = _is_member_ptr_helper<un_cv_t<T>>::value;
+
+template<typename T> concept is_member_func_ptr = is_member_ptr<T> && _is_member_ptr_helper<un_cv_t<T>>::kIsFunc;
+template<typename T> concept is_member_data_ptr = is_member_ptr<T> && !_is_member_ptr_helper<un_cv_t<T>>::kIsFunc;
+
 template<typename T> concept is_object = !is_void<T> && !is_ref<T> && !is_func<T>;

-template<typename T>        struct _is_array_helper       : false_type {};
-template<typename T>        struct _is_array_helper<T[]>  : true_type  {};
-template<typename T, int N> struct _is_array_helper<T[N]> : true_type  {};
+template<typename T>        struct _array_helper       : false_type { using type = T; };
+template<typename T>        struct _array_helper<T[]>  : true_type  { using type = T; };
+template<typename T, int N> struct _array_helper<T[N]> : true_type  { using type = T; };

-template<typename T> concept is_array = _is_array_helper<T>::value;
+template<typename T> concept is_array = _array_helper<T>::value;
+
+template<typename T> using remove_extent_t = _array_helper<T>::type;
+
+template<typename T>
+using decay_t =
+    select_t<
+        is_array<un_ref_t<T>>,
+        as_ptr_t<remove_extent_t<un_ref_t<T>>>,
+        select_t<
+            is_func<un_ref_t<T>>,
+            as_ptr_t<un_ref_t<T>>,
+            un_cv_t<un_ref_t<T>>>>;

 template<typename T> struct _is_floating_point_helper         : false_type {};
 template<>           struct _is_floating_point_helper<float>  : true_type  {};
@ -203,25 +239,111 @@ template<>           struct _is_floating_point_helper<double> : true_type  {};

 template<typename T> concept is_floating_point = _is_floating_point_helper<un_cv_t<T>>::value;

-template<typename T> struct _is_integer_helper           : false_type {};
-template<>           struct _is_integer_helper<int8_t>   : true_type  {};
-template<>           struct _is_integer_helper<int16_t>  : true_type  {};
-template<>           struct _is_integer_helper<int32_t>  : true_type  {};
-template<>           struct _is_integer_helper<int64_t>  : true_type  {};
-template<>           struct _is_integer_helper<uint8_t>  : true_type  {};
-template<>           struct _is_integer_helper<uint16_t> : true_type  {};
-template<>           struct _is_integer_helper<uint32_t> : true_type  {};
-template<>           struct _is_integer_helper<uint64_t> : true_type  {};
+template<typename T> struct _integer_traits
+{
+    static constexpr bool kSigned = false;
+    static constexpr bool kUnsigned = false;
+};

-template<typename T> concept is_integer = _is_integer_helper<un_cv_t<T>>::value;
+template<> struct _integer_traits<uint8_t>
+{
+    static constexpr bool kSigned = false;
+    static constexpr bool kUnsigned = true;
+    using as_signed   = int8_t;
+    using as_unsigned = uint8_t;
+};
+
+template<> struct _integer_traits<uint16_t>
+{
+    static constexpr bool kSigned = false;
+    static constexpr bool kUnsigned = true;
+    using as_signed   = int16_t;
+    using as_unsigned = uint16_t;
+};
+
+template<> struct _integer_traits<uint32_t>
+{
+    static constexpr bool kSigned = false;
+    static constexpr bool kUnsigned = true;
+    using as_signed   = int32_t;
+    using as_unsigned = uint32_t;
+};
+
+template<> struct _integer_traits<uint64_t>
+{
+    static constexpr bool kSigned = false;
+    static constexpr bool kUnsigned = true;
+    using as_signed   = int64_t;
+    using as_unsigned = uint64_t;
+};
+
+template<> struct _integer_traits<int8_t>
+{
+    static constexpr bool kSigned = true;
+    static constexpr bool kUnsigned = false;
+    using as_unsigned = uint8_t;
+    using as_signed   = int8_t;
+};
+
+template<> struct _integer_traits<int16_t>
+{
+    static constexpr bool kSigned = true;
+    static constexpr bool kUnsigned = false;
+    using as_unsigned = uint16_t;
+    using as_signed   = int16_t;
+};
+
+template<> struct _integer_traits<int32_t>
+{
+    static constexpr bool kSigned = true;
+    static constexpr bool kUnsigned = false;
+    using as_unsigned = uint32_t;
+    using as_signed   = int32_t;
+};
+
+template<> struct _integer_traits<int64_t>
+{
+    static constexpr bool kSigned = true;
+    static constexpr bool kUnsigned = false;
+    using as_unsigned = uint64_t;
+    using as_signed   = int64_t;
+};
+
+template<typename T> concept is_signed_integer   = _integer_traits<T>::kSigned;
+template<typename T> concept is_unsigned_integer = _integer_traits<T>::kUnsigned;
+
+template<typename T> concept is_integer = is_signed_integer<T> || is_unsigned_integer<T>;
+
+template<is_integer T> using as_unsigned_integer = _integer_traits<T>::as_unsigned;
+template<is_integer T> using as_signed_integer   = _integer_traits<T>::as_signed;
+
+template<int N>
+struct smallest_unsigned_integer_type_for_width_helper { using type = void; };
+
+template<int N> requires (N >= 1 and N <= 8)
+struct smallest_unsigned_integer_type_for_width_helper<N> { using type = uint8_t; };
+
+template<int N> requires (N >= 9 and N <= 16)
+struct smallest_unsigned_integer_type_for_width_helper<N> { using type = uint16_t; };
+
+template<int N> requires (N >= 17 and N <= 32)
+struct smallest_unsigned_integer_type_for_width_helper<N> { using type = uint32_t; };
+
+template<int N> requires (N >= 33 and N <= 64)
+struct smallest_unsigned_integer_type_for_width_helper<N> { using type = uint64_t; };
+
+template<int N> using smallest_unsigned_integer_type_for_width
+    = smallest_unsigned_integer_type_for_width_helper<N>::type;

 template<typename T> concept is_enum = __is_enum(T);

-template<typename T>     struct is_uniquely_represented : false_type {};
-template<is_integer T>   struct is_uniquely_represented<T> : true_type {};
-template<is_enum T>      struct is_uniquely_represented<T> : true_type {};
+template<is_enum T> using underlying_t = __underlying_type(T);
+
+template<typename T>     struct is_uniquely_represented            : false_type {};
+template<is_integer T>   struct is_uniquely_represented<T>         : true_type {};
+template<is_enum T>      struct is_uniquely_represented<T>         : true_type {};
 template<>               struct is_uniquely_represented<uint128_t> : true_type {};
-template<>               struct is_uniquely_represented<byte> : true_type {};
+template<>               struct is_uniquely_represented<byte>      : true_type {};

 template<typename T> concept uniquely_represented = is_uniquely_represented<un_cv_t<T>>::value;

@ -244,29 +366,28 @@ concept has_niche = constructible_from<T, niche_t> && equality_comparable_with<T
 template<typename T>
 concept is_niche = same_as<un_cvref_t<T>, niche_t>;

-template<typename T, typename U>
-concept _derefs_with_indirection_as = requires(T& t)
+template<typename From, typename To>
+concept _dereferenceable_as_convertible = requires(From& t)
 {
-    *t;
-    requires convertible_from<U&, decltype(*t)>;
+    { *t } -> convertible_to<To&>;
 };

-template<typename T, typename U>
-concept _derefs_reference_as = is_ref<T> && convertible_from<U&, T>;
+template<typename From, typename To>
+concept derefs_as = is_object<To> &&
+    (convertible_to<un_ref_t<From>&, To&> || _dereferenceable_as_convertible<un_ref_t<From>, To>);

-template<typename T, typename U>
-concept _derefs_value_as = !is_ref<T> && convertible_from<U&, T&>;
-
-template<typename U, _derefs_with_indirection_as<U> T>
-constexpr U& deref(T&& t) { return static_cast<U&>(*t); }
-
-template<typename U, _derefs_reference_as<U> T>
-constexpr U& deref(T&& t) { return static_cast<U&>(t); }
-
-template<typename U, _derefs_value_as<U> T>
-constexpr U& deref(T&& t) { return static_cast<U&>(t); }
-
-template<typename T, typename U>
-concept derefs_as = _derefs_with_indirection_as<T, U> || _derefs_reference_as<T, U> || _derefs_value_as<T, U>;
+template<typename To, derefs_as<To> From>
+constexpr auto&& deref(From&& from) // NOLINT(*-missing-std-forward)
+{
+    if constexpr (_dereferenceable_as_convertible<From, To>)
+    {
+        using deref_type = decltype(*declval<From&&>());
+        return static_cast<copy_cref_t<deref_type, To>>(*static_cast<From&&>(from));
+    }
+    else
+    {
+        return static_cast<copy_cref_t<From&&, To>>(from);
+    }
+}

 } // namespace asl
--- a/asl/base/meta_tests.cpp
+++ b/asl/base/meta_tests.cpp
@ -135,6 +135,12 @@ static_assert(!asl::is_ref<void>);
 static_assert(!asl::is_ref<void()>);
 static_assert(!asl::is_ref<void() const &&>);

+struct MyClass
+{
+    int data;
+    int fn(int x) { return x; } // NOLINT
+};
+
 static_assert(asl::is_ptr<int*>);
 static_assert(asl::is_ptr<const int* const>);
 static_assert(asl::is_ptr<const volatile int*>);
@ -142,6 +148,28 @@ static_assert(!asl::is_ptr<int>);
 static_assert(!asl::is_ptr<void>);
 static_assert(!asl::is_ptr<void()>);
 static_assert(!asl::is_ptr<void() const &&>);
+static_assert(!asl::is_ptr<int MyClass::*>);
+static_assert(!asl::is_ptr<int (MyClass::*)(int)>);
+
+static_assert(!asl::is_member_ptr<int*>);
+static_assert(!asl::is_member_ptr<void()>);
+static_assert(!asl::is_member_ptr<void() const &&>);
+static_assert(asl::is_member_ptr<int MyClass::*>);
+static_assert(asl::is_member_ptr<int (MyClass::*)(int)>);
+
+static_assert(!asl::is_member_data_ptr<int*>);
+static_assert(!asl::is_member_data_ptr<void()>);
+static_assert(!asl::is_member_data_ptr<void() const &&>);
+static_assert(asl::is_member_data_ptr<int MyClass::*>);
+static_assert(!asl::is_member_data_ptr<int (MyClass::*)(int)>);
+
+static_assert(!asl::is_member_func_ptr<int*>);
+static_assert(!asl::is_member_func_ptr<void()>);
+static_assert(!asl::is_member_func_ptr<void() const &&>);
+static_assert(!asl::is_member_func_ptr<int MyClass::*>);
+static_assert(asl::is_member_func_ptr<int (MyClass::*)(int)>);
+static_assert(asl::is_member_func_ptr<int (MyClass::*)(int) const>);
+static_assert(asl::is_member_func_ptr<int (MyClass::*)(int) volatile &&>);

 static_assert(asl::same_as<int, asl::tame_t<int>>);
 static_assert(asl::same_as<int(), asl::tame_t<int()>>);
@ -189,6 +217,10 @@ static_assert(!asl::is_array<void>);
 static_assert(!asl::is_array<void(int)>);
 static_assert(!asl::is_array<int(float) const && noexcept>);

+static_assert(asl::same_as<int, asl::remove_extent_t<int>>);
+static_assert(asl::same_as<int, asl::remove_extent_t<int[]>>);
+static_assert(asl::same_as<int, asl::remove_extent_t<int[67]>>);
+
 static_assert(asl::same_as<int, asl::un_ref_t<int>>);
 static_assert(asl::same_as<int, asl::un_ref_t<int&>>);
 static_assert(asl::same_as<int, asl::un_ref_t<int&&>>);
@ -205,21 +237,23 @@ class C {};
 class D { public: operator C() { return c; } C c; }; // NOLINT
 class E { public: template<class T> E(T&&) {} }; // NOLINT

-static_assert(asl::convertible_from<Base*, Derived*>);
-static_assert(!asl::convertible_from<Derived*, Base*>);
-static_assert(asl::convertible_from<C, D>);
-static_assert(!asl::convertible_from<C*, Derived*>);
-static_assert(asl::convertible_from<E, Base>);
+static_assert(asl::convertible_to<Derived*, Base*>);
+static_assert(!asl::convertible_to<Base*, Derived*>);
+static_assert(asl::convertible_to<D, C>);
+static_assert(!asl::convertible_to<Derived*, C*>);
+static_assert(asl::convertible_to<Base, E>);

-static_assert(!asl::convertible_from<int16_t(&)[], int32_t(&)[]>);
-static_assert(asl::convertible_from<const int16_t(&)[], int16_t(&)[]>);
-static_assert(asl::convertible_from<const int16_t(&)[], const int16_t(&)[]>);
-static_assert(asl::convertible_from<int16_t(&)[], int16_t(&)[]>);
-static_assert(!asl::convertible_from<int32_t(&)[], int16_t(&)[]>);
-static_assert(!asl::convertible_from<int16_t(&)[], const int16_t(&)[]>);
-static_assert(!asl::convertible_from<C(&)[], D(&)[]>);
+static_assert(!asl::convertible_to<int32_t(&)[], int16_t(&)[]>);
+static_assert(asl::convertible_to<int16_t(&)[], const int16_t(&)[]>);
+static_assert(asl::convertible_to<const int16_t(&)[], const int16_t(&)[]>);
+static_assert(asl::convertible_to<int16_t(&)[], int16_t(&)[]>);
+static_assert(!asl::convertible_to<int16_t(&)[], int32_t(&)[]>);
+static_assert(!asl::convertible_to<const int16_t(&)[], int16_t(&)[]>);
+static_assert(!asl::convertible_to<D(&)[], C(&)[]>);

 static_assert(asl::derived_from<Derived, Base>);
+static_assert(asl::derived_from<Derived, Derived>);
+static_assert(asl::derived_from<Base, Base>);
 static_assert(!asl::derived_from<Base, Derived>);
 static_assert(!asl::derived_from<D, C>);
 static_assert(!asl::derived_from<C, D>);
@ -227,9 +261,20 @@ static_assert(!asl::derived_from<uint8_t, uint16_t>);
 static_assert(!asl::derived_from<uint16_t, uint8_t>);
 static_assert(!asl::derived_from<int, int>);

+static_assert(asl::same_or_derived_from<Derived, Base>);
+static_assert(asl::same_or_derived_from<Derived, Derived>);
+static_assert(asl::same_or_derived_from<Base, Base>);
+static_assert(!asl::same_or_derived_from<Base, Derived>);
+static_assert(!asl::same_or_derived_from<D, C>);
+static_assert(!asl::same_or_derived_from<C, D>);
+static_assert(!asl::same_or_derived_from<uint8_t, uint16_t>);
+static_assert(!asl::same_or_derived_from<uint16_t, uint8_t>);
+static_assert(asl::same_or_derived_from<int, int>);
+
 static_assert(!asl::is_const<int>);
 static_assert(asl::is_const<const int>);
 static_assert(!asl::is_const<const int*>);
+static_assert(!asl::is_const<const int&>);
 static_assert(asl::is_const<int* const>);

 static_assert(asl::is_floating_point<float>);
@ -255,16 +300,22 @@ static_assert(asl::is_enum<Enum2>);

 static_assert(asl::derefs_as<int, int>);
 static_assert(asl::derefs_as<int*, int>);
+static_assert(!asl::derefs_as<const int*, int>);
 static_assert(asl::derefs_as<int&, int>);
+static_assert(!asl::derefs_as<const int&, int>);
 static_assert(asl::derefs_as<asl::box<int>, int>);

 static_assert(asl::derefs_as<Derived, Base>);
+static_assert(!asl::derefs_as<Base, Derived>);
 static_assert(asl::derefs_as<Derived*, Base>);
 static_assert(asl::derefs_as<Derived&, Base>);
+static_assert(!asl::derefs_as<Base&, Derived>);
 static_assert(asl::derefs_as<asl::box<Derived>, Base>);
+static_assert(asl::derefs_as<asl::box<Derived>, Derived>);
+static_assert(asl::derefs_as<asl::box<Base>, Base>);

 static void wants_int(int) {}
-static void wants_base(Base&) {}
+static void wants_base(const Base&) {}
 static void wants_base_ptr(Base*) {}

 ASL_TEST(deref)
@ -285,10 +336,11 @@ ASL_TEST(deref)
    wants_base(asl::deref<Base>(&c));
    wants_base(asl::deref<Base>(d));

-    wants_base_ptr(&asl::deref<Base>(Derived{}));
    wants_base_ptr(&asl::deref<Base>(c));
    wants_base_ptr(&asl::deref<Base>(&c));
    wants_base_ptr(&asl::deref<Base>(d));
+
+    wants_base(asl::deref<Base>(std::move(d)));
 }

 static_assert(asl::same_as<asl::copy_cref_t<int, float>, float>);
@ -311,3 +363,65 @@ static_assert(asl::same_as<asl::copy_cref_t<const int&, const float>, const floa
 static_assert(asl::same_as<asl::copy_cref_t<const int&, float&&>, const float&>);
 static_assert(asl::same_as<asl::copy_cref_t<const int&, const float&>, const float&>);

+static_assert(asl::same_as<asl::copy_const_t<int, float>, float>);
+static_assert(asl::same_as<asl::copy_const_t<int, const float>, float>);
+
+static_assert(asl::same_as<asl::copy_const_t<const int, float>, const float>);
+static_assert(asl::same_as<asl::copy_const_t<const int, const float>, const float>);
+
+static_assert(asl::same_as<asl::copy_const_t<const int*, float>, float>);
+static_assert(asl::same_as<asl::copy_const_t<int* const, float>, const float>);
+
+static_assert(asl::same_as<asl::decay_t<int>, int>);
+static_assert(!asl::same_as<asl::decay_t<int>, float>);
+static_assert(asl::same_as<asl::decay_t<int&>, int>);
+static_assert(asl::same_as<asl::decay_t<int&&>, int>);
+static_assert(asl::same_as<asl::decay_t<const int&>, int>);
+static_assert(asl::same_as<asl::decay_t<int[2]>, int*>);
+static_assert(!asl::same_as<asl::decay_t<int[4][2]>, int*>);
+static_assert(!asl::same_as<asl::decay_t<int[4][2]>, int**>);
+static_assert(asl::same_as<asl::decay_t<int[4][2]>, int(*)[2]>);
+static_assert(asl::same_as<asl::decay_t<int(int)>, int(*)(int)>);
+
+enum EnumU8 : uint8_t {};
+enum EnumI64 : int64_t {};
+
+static_assert(asl::same_as<asl::underlying_t<EnumU8>, uint8_t>);
+static_assert(asl::same_as<asl::underlying_t<EnumI64>, int64_t>);
+
+static_assert(!asl::is_integer<EnumU8>);
+static_assert(!asl::is_integer<EnumI64>);
+
+static_assert(asl::same_as<asl::as_unsigned_integer<uint8_t>,  uint8_t>);
+static_assert(asl::same_as<asl::as_unsigned_integer<uint16_t>, uint16_t>);
+static_assert(asl::same_as<asl::as_unsigned_integer<uint32_t>, uint32_t>);
+static_assert(asl::same_as<asl::as_unsigned_integer<uint64_t>, uint64_t>);
+
+static_assert(asl::same_as<asl::as_unsigned_integer<int8_t>,  uint8_t>);
+static_assert(asl::same_as<asl::as_unsigned_integer<int16_t>, uint16_t>);
+static_assert(asl::same_as<asl::as_unsigned_integer<int32_t>, uint32_t>);
+static_assert(asl::same_as<asl::as_unsigned_integer<int64_t>, uint64_t>);
+
+static_assert(asl::same_as<asl::as_signed_integer<uint8_t>,  int8_t>);
+static_assert(asl::same_as<asl::as_signed_integer<uint16_t>, int16_t>);
+static_assert(asl::same_as<asl::as_signed_integer<uint32_t>, int32_t>);
+static_assert(asl::same_as<asl::as_signed_integer<uint64_t>, int64_t>);
+
+static_assert(asl::same_as<asl::as_signed_integer<int8_t>,  int8_t>);
+static_assert(asl::same_as<asl::as_signed_integer<int16_t>, int16_t>);
+static_assert(asl::same_as<asl::as_signed_integer<int32_t>, int32_t>);
+static_assert(asl::same_as<asl::as_signed_integer<int64_t>, int64_t>);
+
+static_assert(asl::same_as<asl::smallest_unsigned_integer_type_for_width<1>, uint8_t>);
+static_assert(asl::same_as<asl::smallest_unsigned_integer_type_for_width<2>, uint8_t>);
+static_assert(asl::same_as<asl::smallest_unsigned_integer_type_for_width<4>, uint8_t>);
+static_assert(asl::same_as<asl::smallest_unsigned_integer_type_for_width<8>, uint8_t>);
+static_assert(asl::same_as<asl::smallest_unsigned_integer_type_for_width<12>, uint16_t>);
+static_assert(asl::same_as<asl::smallest_unsigned_integer_type_for_width<16>, uint16_t>);
+static_assert(asl::same_as<asl::smallest_unsigned_integer_type_for_width<20>, uint32_t>);
+static_assert(asl::same_as<asl::smallest_unsigned_integer_type_for_width<30>, uint32_t>);
+static_assert(asl::same_as<asl::smallest_unsigned_integer_type_for_width<31>, uint32_t>);
+static_assert(asl::same_as<asl::smallest_unsigned_integer_type_for_width<32>, uint32_t>);
+static_assert(asl::same_as<asl::smallest_unsigned_integer_type_for_width<50>, uint64_t>);
+static_assert(asl::same_as<asl::smallest_unsigned_integer_type_for_width<63>, uint64_t>);
+static_assert(asl::same_as<asl::smallest_unsigned_integer_type_for_width<64>, uint64_t>);
--- a/asl/base/numeric.hpp
+++ b/asl/base/numeric.hpp
@ -0,0 +1,101 @@
+// Copyright 2025 Steven Le Rouzic
+//
+// SPDX-License-Identifier: BSD-3-Clause
+
+#pragma once
+
+#include "asl/base/integers.hpp"
+#include "asl/base/float.hpp"
+#include "asl/base/bit.hpp"
+#include "asl/base/meta.hpp"
+#include "asl/base/assert.hpp"
+
+namespace asl
+{
+
+template<is_integer T>
+constexpr bool is_pow2(T x)
+{
+    using unsigned_type = as_unsigned_integer<T>;
+    return x > 0 && has_single_bit(static_cast<unsigned_type>(x));
+}
+
+template<is_integer T>
+constexpr T round_down_pow2(T x, T div)
+{
+    ASL_ASSERT(is_pow2(div));
+    return x & (-div);
+}
+
+template<is_integer T>
+constexpr T round_up_pow2(T x, T div)
+{
+    ASL_ASSERT(is_pow2(div));
+    return (x + (div - 1)) & (-div);
+}
+
+template<typename T>
+concept is_numeric = is_integer<T> || is_floating_point<T>;
+
+template<is_numeric T>
+constexpr T min(T a, T b)
+{
+    return (a <= b) ? a : b;
+}
+
+template<is_numeric T>
+constexpr T max(T a, T b)
+{
+    return (a >= b) ? a : b;
+}
+
+template<is_numeric T>
+constexpr T clamp(T x, T a, T b)
+{
+    return min(max(x, a), b);
+}
+
+constexpr float32_t abs(float32_t x) { return __builtin_fabsf(x); }
+constexpr float64_t abs(float64_t x) { return __builtin_fabs(x); }
+
+template<is_floating_point T>
+bool are_nearly_equal(T a, T b)
+{
+    // This is a fast path for identical values and correctly handles
+    // the case where +0.0 == -0.0.
+    #pragma clang diagnostic push
+    #pragma clang diagnostic ignored "-Wfloat-equal"
+    if (a == b) { return true; }
+    #pragma clang diagnostic pop
+
+    // NaNs are never equal to anything, including themselves.
+    if (is_nan(a) || is_nan(b)) { return false; }
+
+    // Infinities are only equal if they are identical (which is handled by the
+    // `a == b` check above). If one is infinity and the other is not, they
+    // are not equal. The relative comparison below would fail with infinities.
+    if (is_infinity(a) || is_infinity(b)) { return false; }
+
+    static constexpr T kMin = float_traits<T>::kSmallest;
+    static constexpr T kEps = float_traits<T>::kEpsilon;
+
+    const T abs_a = abs(a);
+    const T abs_b = abs(b);
+    const T abs_diff = abs(a - b);
+
+    // The relative error comparison (`|a-b| <= ε * max(|a|, |b|)`) breaks
+    // down when `a` and `b` are near zero. In this case, we switch to an
+    // absolute error comparison. `DBL_MIN` is the smallest positive
+    // normalized double, so it's a good threshold for this check.
+    if (abs_a < kMin || abs_b < kMin)
+    {
+        return abs_diff < kEps;
+    }
+
+    // For all other cases, we use the standard relative error formula.
+    // The error is scaled by the magnitude of the numbers.
+    return abs_diff <= kEps * max(abs_a, abs_b);
+}
+
+} // namespace asl
+
--- a/asl/base/numeric_tests.cpp
+++ b/asl/base/numeric_tests.cpp
@ -0,0 +1,68 @@
+// Copyright 2025 Steven Le Rouzic
+//
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include "asl/base/numeric.hpp"
+
+#include "asl/testing/testing.hpp"
+
+ASL_TEST(is_pow2)
+{
+    ASL_TEST_EXPECT(asl::is_pow2(4));
+    ASL_TEST_EXPECT(asl::is_pow2(65536));
+    ASL_TEST_EXPECT(!asl::is_pow2(6));
+    ASL_TEST_EXPECT(!asl::is_pow2(1978));
+    ASL_TEST_EXPECT(!asl::is_pow2(0));
+    ASL_TEST_EXPECT(asl::is_pow2(4U));
+    ASL_TEST_EXPECT(asl::is_pow2(uint64_t{65536}));
+}
+
+ASL_TEST(round_down_pow2) // NOLINT
+{
+    ASL_TEST_EXPECT(asl::round_down_pow2(0, 1) == 0);
+    ASL_TEST_EXPECT(asl::round_down_pow2(1, 1) == 1);
+    ASL_TEST_EXPECT(asl::round_down_pow2(2, 1) == 2);
+    ASL_TEST_EXPECT(asl::round_down_pow2(3, 1) == 3);
+    ASL_TEST_EXPECT(asl::round_down_pow2(-1, 1) == -1);
+    ASL_TEST_EXPECT(asl::round_down_pow2(-2, 1) == -2);
+    ASL_TEST_EXPECT(asl::round_down_pow2(-3, 1) == -3);
+
+    ASL_TEST_EXPECT(asl::round_down_pow2(0U, 1U) == 0U);
+    ASL_TEST_EXPECT(asl::round_down_pow2(1U, 1U) == 1U);
+    ASL_TEST_EXPECT(asl::round_down_pow2(2U, 1U) == 2U);
+    ASL_TEST_EXPECT(asl::round_down_pow2(3U, 1U) == 3U);
+
+    ASL_TEST_EXPECT(asl::round_down_pow2(0, 16) == 0);
+    ASL_TEST_EXPECT(asl::round_down_pow2(1, 16) == 0);
+    ASL_TEST_EXPECT(asl::round_down_pow2(8, 16) == 0);
+    ASL_TEST_EXPECT(asl::round_down_pow2(15, 16) == 0);
+    ASL_TEST_EXPECT(asl::round_down_pow2(16, 16) == 16);
+    ASL_TEST_EXPECT(asl::round_down_pow2(17, 16) == 16);
+    ASL_TEST_EXPECT(asl::round_down_pow2(255, 16) == 240);
+    ASL_TEST_EXPECT(asl::round_down_pow2(-255, 16) == -256);
+}
+
+ASL_TEST(round_up_pow2) // NOLINT
+{
+    ASL_TEST_EXPECT(asl::round_up_pow2(0, 1) == 0);
+    ASL_TEST_EXPECT(asl::round_up_pow2(1, 1) == 1);
+    ASL_TEST_EXPECT(asl::round_up_pow2(2, 1) == 2);
+    ASL_TEST_EXPECT(asl::round_up_pow2(3, 1) == 3);
+    ASL_TEST_EXPECT(asl::round_up_pow2(-1, 1) == -1);
+    ASL_TEST_EXPECT(asl::round_up_pow2(-2, 1) == -2);
+    ASL_TEST_EXPECT(asl::round_up_pow2(-3, 1) == -3);
+
+    ASL_TEST_EXPECT(asl::round_up_pow2(0U, 1U) == 0U);
+    ASL_TEST_EXPECT(asl::round_up_pow2(1U, 1U) == 1U);
+    ASL_TEST_EXPECT(asl::round_up_pow2(2U, 1U) == 2U);
+    ASL_TEST_EXPECT(asl::round_up_pow2(3U, 1U) == 3U);
+
+    ASL_TEST_EXPECT(asl::round_up_pow2(0, 16) == 0);
+    ASL_TEST_EXPECT(asl::round_up_pow2(1, 16) == 16);
+    ASL_TEST_EXPECT(asl::round_up_pow2(8, 16) == 16);
+    ASL_TEST_EXPECT(asl::round_up_pow2(15, 16) == 16);
+    ASL_TEST_EXPECT(asl::round_up_pow2(16, 16) == 16);
+    ASL_TEST_EXPECT(asl::round_up_pow2(17, 16) == 32);
+    ASL_TEST_EXPECT(asl::round_up_pow2(255, 16) == 256);
+    ASL_TEST_EXPECT(asl::round_up_pow2(-255, 16) == -240);
+}
--- a/asl/base/utility.hpp
+++ b/asl/base/utility.hpp
@ -7,31 +7,59 @@
 #include "asl/base/meta.hpp"
 #include "asl/base/assert.hpp"

-#define ASL_MOVE(...) (static_cast<::asl::un_ref_t<decltype(__VA_ARGS__)>&&>(__VA_ARGS__))
+namespace std
+{

-#define ASL_FWD(expr_) (static_cast<decltype(expr_)&&>(expr_))
+template<typename T>
+[[nodiscard]] constexpr asl::un_ref_t<T>&& move(T&& t) noexcept // NOLINT
+{
+    return static_cast<asl::un_ref_t<T>&&>(t);
+}

-#define ASL_FWD_LIKE(ref_, expr_) (static_cast<::asl::copy_cref_t<ref_, decltype(expr_)&&>>(expr_))
+template<typename T>
+[[nodiscard]] constexpr T&& forward(asl::un_ref_t<T>& t) noexcept // NOLINT
+{
+    return static_cast<T&&>(t);
+}
+
+template< class T >
+[[nodiscard]] constexpr T&& forward(asl::un_ref_t<T>&& t) noexcept // NOLINT
+{
+    return static_cast<T&&>(t);
+}
+
+template<typename T, typename U>
+[[nodiscard]] constexpr auto forward_like(U&& x) noexcept -> asl::copy_cref_t<T, U> // NOLINT
+{
+    using return_type = asl::copy_cref_t<T, U&&>;
+    return static_cast<return_type>(x);
+}
+
+template<typename T>
+[[nodiscard]] constexpr T* launder(T* ptr) noexcept // NOLINT
+    requires (!asl::is_func<T> && !asl::is_void<T>)
+{
+    return __builtin_launder(ptr);
+}
+
+} // namespace std

 namespace asl
 {

-struct in_place_t {};
-static constexpr in_place_t in_place{};
-
 template<moveable T>
 constexpr void swap(T& a, T& b)
 {
-    T tmp{ASL_MOVE(a)};
-    a = ASL_MOVE(b);
-    b = ASL_MOVE(tmp);
+    T tmp{std::move(a)};
+    a = std::move(b);
+    b = std::move(tmp);
 }

 template<typename T, typename U>
 T exchange(T& obj, U&& new_value)
 {
-    T old_value = ASL_MOVE(obj);
-    obj = ASL_FWD(new_value);
+    T old_value = std::move(obj);
+    obj = std::forward<U>(new_value);
    return old_value;
 }

@ -41,62 +69,37 @@ constexpr U bit_cast(T value) requires (sizeof(T) == sizeof(U))
    return __builtin_bit_cast(U, value);
 }

-template<typename T>
-constexpr T min(T a, T b)
+template<is_enum T>
+constexpr auto to_underlying(T value)
 {
-    return (a <= b) ? a : b;
-}
-
-template<typename T>
-constexpr T max(T a, T b)
-{
-    return (a >= b) ? a : b;
-}
-
-constexpr uint64_t round_up_pow2(uint64_t v)
-{
-    ASL_ASSERT(v <= 0x8000'0000'0000'0000);
-
-    v -= 1;
-
-    v |= v >> 1;
-    v |= v >> 2;
-    v |= v >> 4;
-    v |= v >> 8;
-    v |= v >> 16;
-    v |= v >> 32;
-
-    return v + 1;
-}
-
-constexpr bool is_pow2(isize_t v)
-{
-    return v > 0 && ((v - 1) & v) == 0;
+    return static_cast<underlying_t<T>>(value);
 }

+// NOLINTBEGIN(*-macro-parentheses)
 #define ASL_DELETE_COPY(T)                         \
    T(const T&) = delete;                          \
-    T& operator=(const T&) = delete;
+    T& operator=(const T&) = delete

 #define ASL_DELETE_MOVE(T)                         \
    T(T&&) = delete;                               \
-    T& operator=(T&&) = delete;
+    T& operator=(T&&) = delete

 #define ASL_DELETE_COPY_MOVE(T)                    \
-    ASL_DELETE_COPY(T)                             \
+    ASL_DELETE_COPY(T);                            \
    ASL_DELETE_MOVE(T)

 #define ASL_DEFAULT_COPY(T)                         \
    T(const T&) = default;                          \
-    T& operator=(const T&) = default;
+    T& operator=(const T&) = default

 #define ASL_DEFAULT_MOVE(T)                         \
    T(T&&) = default;                               \
-    T& operator=(T&&) = default;
+    T& operator=(T&&) = default

 #define ASL_DEFAULT_COPY_MOVE(T)                    \
-    ASL_DEFAULT_COPY(T)                             \
+    ASL_DEFAULT_COPY(T);                            \
    ASL_DEFAULT_MOVE(T)
+// NOLINTEND(*-macro-parentheses)

 #define ASL_CONCAT2(A, B) A##B
 #define ASL_CONCAT(A, B) ASL_CONCAT2(A, B)
--- a/asl/base/utility_tests.cpp
+++ b/asl/base/utility_tests.cpp
@ -12,28 +12,28 @@ template<typename T> static constexpr int identify(T&&)       { return 4; }

 struct IdentifySelf
 {
-    constexpr int get(this auto&& self) { return identify(ASL_FWD(self)); }
+    constexpr int get(this auto&& self) { return identify(std::forward<decltype(self)>(self)); }
 };

-static int get_const_lref(const IdentifySelf& i)  { return ASL_FWD(i).get(); }
-static int get_const_rref(const IdentifySelf&& i) { return ASL_FWD(i).get(); }
-static int get_lref(IdentifySelf& i)              { return ASL_FWD(i).get(); }
-static int get_rref(IdentifySelf&& i)             { return ASL_FWD(i).get(); }
+static int get_const_lref(const IdentifySelf& i)  { return i.get(); }
+static int get_const_rref(const IdentifySelf&& i) { return std::move(i).get(); } // NOLINT
+static int get_lref(IdentifySelf& i)              { return i.get(); }
+static int get_rref(IdentifySelf&& i)             { return std::move(i).get(); } // NOLINT

 ASL_TEST(forward)
 {
-    IdentifySelf id;
-    ASL_TEST_EXPECT(get_const_lref(id) == 1);
+    IdentifySelf id{};
+    ASL_TEST_EXPECT(get_const_lref(IdentifySelf{}) == 1);
    ASL_TEST_EXPECT(get_lref(id) == 3);
-    ASL_TEST_EXPECT(get_const_rref(ASL_MOVE(id)) == 2);
-    ASL_TEST_EXPECT(get_rref(ASL_MOVE(id)) == 4);
+    ASL_TEST_EXPECT(get_const_rref(IdentifySelf{}) == 2);
+    ASL_TEST_EXPECT(get_rref(IdentifySelf{}) == 4);
 }

 ASL_TEST(move)
 {
    IdentifySelf id;
    ASL_TEST_EXPECT(id.get() == 3);
-    ASL_TEST_EXPECT(ASL_MOVE(id).get() == 4);
+    ASL_TEST_EXPECT(IdentifySelf{}.get() == 4);
 }

 struct Level1
@ -51,33 +51,50 @@ struct Level3
    Level2 deeper;
 };

-static int get_const_lref(const Level3& i)  { return ASL_FWD(i).deeper.deeper.id.get(); }
-static int get_const_rref(const Level3&& i) { return ASL_FWD(i).deeper.deeper.id.get(); }
-static int get_lref(Level3& i)              { return ASL_FWD(i).deeper.deeper.id.get(); }
-static int get_rref(Level3&& i)             { return ASL_FWD(i).deeper.deeper.id.get(); }
+static int get_const_lref(const Level3& i)  { return i.deeper.deeper.id.get(); }
+static int get_const_rref(const Level3&& i) { return std::move(i).deeper.deeper.id.get(); }
+static int get_lref(Level3& i)              { return i.deeper.deeper.id.get(); }
+static int get_rref(Level3&& i)             { return std::move(i).deeper.deeper.id.get(); }

 ASL_TEST(forward2)
 {
    Level3 id{};
    ASL_TEST_EXPECT(get_const_lref(id) == 1);
    ASL_TEST_EXPECT(get_lref(id) == 3);
-    ASL_TEST_EXPECT(get_const_rref(ASL_MOVE(id)) == 2);
-    ASL_TEST_EXPECT(get_rref(ASL_MOVE(id)) == 4);
+    ASL_TEST_EXPECT(get_const_rref(Level3{}) == 2);
+    ASL_TEST_EXPECT(get_rref(Level3{}) == 4);
 }

 template<typename T>
-static int test_fwd_like(T&& t)
+static int test_fwd_like(T) // NOLINT
 {
-    IdentifySelf id;
-    return ASL_FWD_LIKE(decltype(t), id).get();
+    const IdentifySelf id;
+    return std::forward_like<T>(id).get();
 }

 ASL_TEST(forward_like)
 {
    int x{};
-    ASL_TEST_EXPECT(test_fwd_like<const int&>(x) == 1);
+    ASL_TEST_EXPECT(test_fwd_like<const int&>(7) == 1);
    ASL_TEST_EXPECT(test_fwd_like<int&>(x) == 3);
-    ASL_TEST_EXPECT(test_fwd_like<const int&&>(ASL_MOVE(x)) == 2);
-    ASL_TEST_EXPECT(test_fwd_like<int&&>(ASL_MOVE(x)) == 4);
+    ASL_TEST_EXPECT(test_fwd_like<const int&&>(8) == 2);
+    ASL_TEST_EXPECT(test_fwd_like<int&&>(9) == 4);
 }

+enum class Enum : int // NOLINT
+{
+    kOne = 1,
+    kTwo = 2,
+};
+
+enum Enum2 : int // NOLINT
+{
+    kOne = 1,
+    kTwo = 2,
+};
+
+static_assert(asl::to_underlying(Enum::kOne) == 1);
+static_assert(asl::to_underlying(Enum::kTwo) == 2);
+static_assert(asl::to_underlying(kOne) == 1);
+static_assert(asl::to_underlying(kTwo) == 2);
+
--- a/asl/containers/BUILD.bazel
+++ b/asl/containers/BUILD.bazel
@ -13,6 +13,7 @@ cc_library(
    ],
    deps = [
        "//asl/memory",
+        "//asl/memory:allocator",
        "//asl/base",
        "//asl/types:span",
        "//asl/hashing",
@ -20,6 +21,22 @@ cc_library(
    visibility = ["//visibility:public"],
 )

+cc_library(
+    name = "chunked_buffer",
+    hdrs = [
+        "chunked_buffer.hpp",
+    ],
+    deps = [
+        "//asl/memory",
+        "//asl/memory:allocator",
+        "//asl/base",
+        "//asl/containers:buffer",
+        "//asl/types:array",
+        "//asl/types:maybe_uninit",
+    ],
+    visibility = ["//visibility:public"],
+)
+
 cc_library(
    name = "hash_set",
    hdrs = [
@ -28,6 +45,7 @@ cc_library(
    deps = [
        "//asl/base",
        "//asl/memory",
+        "//asl/memory:allocator",
        "//asl/types:maybe_uninit",
        "//asl/hashing",
    ],
@ -42,6 +60,7 @@ cc_library(
    deps = [
        "//asl/base",
        "//asl/memory",
+        "//asl/memory:allocator",
        "//asl/hashing",
        ":hash_set",
    ],
@ -72,6 +91,7 @@ cc_library(
    ],
 ) for name in [
    "buffer",
+    "chunked_buffer",
    "hash_map",
    "hash_set",
    "intrusive_list",
--- a/asl/containers/buffer.hpp
+++ b/asl/containers/buffer.hpp
@ -9,13 +9,15 @@
 #include "asl/memory/memory.hpp"
 #include "asl/base/annotations.hpp"
 #include "asl/base/assert.hpp"
+#include "asl/base/bit.hpp"
 #include "asl/types/span.hpp"
 #include "asl/hashing/hash.hpp"

 namespace asl
 {

-template<is_object T, allocator Allocator = DefaultAllocator>
+template<typename T, allocator Allocator = DefaultAllocator>
+requires is_object<T> && moveable<T>
 class buffer
 {
    T*         m_data{};
@ -46,7 +48,7 @@ private:
    static_assert(align_of<T*> == align_of<isize_t>);
    static_assert(align_of<T*> == align_of<size_t>);

-    constexpr size_t load_size_encoded() const
+    [[nodiscard]] constexpr size_t load_size_encoded() const
    {
        size_t s{};
        asl::memcpy(&s, &m_size_encoded_, sizeof(size_t));
@ -80,28 +82,31 @@ private:
        {
            return is_on_heap(size_encoded)
                ? static_cast<isize_t>(size_encoded & (~kOnHeapMask))
-                : static_cast<isize_t>(size_encoded >> 56);
+                : static_cast<isize_t>(size_encoded >> 56U);
        }
    }

-    constexpr bool is_on_heap() const
+    [[nodiscard]] constexpr bool is_on_heap() const
    {
        return is_on_heap(load_size_encoded());
    }

-    constexpr T* push_uninit()
+    constexpr void* push_uninit()
    {
-        isize_t sz = size();
+        const isize_t sz = size();
        resize_uninit_inner(sz + 1);
        return data() + sz;
    }

    constexpr void resize_uninit_inner(isize_t new_size)
    {
-        isize_t old_size = size();
-        if (!trivially_destructible<T> && new_size < old_size)
+        if constexpr (!trivially_destructible<T>)
        {
-            destroy_n(data() + new_size, old_size - new_size);
+            const isize_t old_size = size();
+            if (new_size < old_size)
+            {
+                destroy_n(data() + new_size, old_size - new_size);
+            }
        }
        reserve_capacity(new_size);
        set_size(new_size);
@ -110,7 +115,9 @@ private:
    constexpr void set_size_inline(isize_t new_size)
    {
        ASL_ASSERT(new_size >= 0 && new_size <= kInlineCapacity);
-        size_t size_encoded = (load_size_encoded() & size_t{0x00ff'ffff'ffff'ffff}) | (bit_cast<size_t>(new_size) << 56);
+        const size_t size_encoded =
+            (load_size_encoded() & size_t{0x00ff'ffff'ffff'ffff})
+            | (bit_cast<size_t>(new_size) << 56U);
        store_size_encoded(size_encoded);
    }

@ -132,20 +139,28 @@ private:
    {
        if (other.is_on_heap())
        {
+            // If the other in on heap, destroy here and adopt their
+            // data. We'll soon adopt the allocator as well.
            destroy();
            m_data = other.m_data;
            m_capacity = other.m_capacity;
            store_size_encoded(other.load_size_encoded());
        }
-        else if (trivially_move_constructible<T>)
-        {
-            destroy();
-            asl::memcpy(this, &other, kInlineRegionSize);
-        }
        else if (!assign || m_allocator == other.m_allocator)
        {
-            isize_t other_n = other.size();
-            isize_t this_n = size();
+            // If allocators are compatible, we can move other's inline
+            // data here, even if it's on heap here, because that
+            // memory can be freed by other's allocator, which we will
+            // soon adopt.
+            //
+            // @Note There is an argument to be made for not doing this and
+            // instead destroying our data here and moving into inline
+            // storage, which frees one allocation. But also this avoids
+            // freeing. So I don't know.
+            // Maybe If this storage is much much larger than the inline
+            // data, it's worth freeing.
+            const isize_t other_n = other.size();
+            const isize_t this_n = size();
            resize_uninit_inner(other_n);
            if (other_n <= this_n)
            {
@ -159,25 +174,42 @@ private:
        }
        else
        {
+            // Otherwise, if we have to free, because the allocators are
+            // not compatible, well we free and move into our inline
+            // storage region.
+            // There is an optimization here when the data is trivially
+            // move constructible (which implies trivially destructible),
+            // we copy the whole inline region, which includes the size.
+            // Very magic.
+
            destroy();
-            isize_t n = other.size();
-            ASL_ASSERT(n <= kInlineCapacity);
-            relocate_uninit_n(data(), other.data(), n);
-            set_size_inline(n);
+            if constexpr (trivially_move_constructible<T>)
+            {
+                ASL_ASSERT(!is_on_heap());
+                asl::memcpy(this, &other, kInlineRegionSize);
+            }
+            else
+            {
+                const isize_t n = other.size();
+                ASL_ASSERT(n <= kInlineCapacity);
+                resize_uninit_inner(n);
+                ASL_ASSERT(!is_on_heap());
+                relocate_uninit_n(data(), other.data(), n);
+            }
        }

        other.set_size_inline(0);

        if (assign)
        {
-            m_allocator = ASL_MOVE(other.m_allocator);
+            m_allocator = std::move(other.m_allocator);
        }
    }

    void copy_range(span<const T> to_copy)
    {
-        isize_t this_size = size();
-        isize_t new_size = to_copy.size();
+        const isize_t this_size = size();
+        const isize_t new_size = to_copy.size();

        resize_uninit_inner(to_copy.size());
        ASL_ASSERT(capacity() >= new_size);
@ -209,7 +241,7 @@ private:
        // NOLINTNEXTLINE(*-pointer-arithmetic)
        for (T* it = data_ptr + old_size; it < end; ++it)
        {
-            construct_at<T>(it, ASL_FWD(args)...);
+            construct_at<T>(it, std::forward<Args>(args)...);
        }
    }

@ -224,11 +256,11 @@ public:
    }

    explicit constexpr buffer(Allocator allocator)
-        : m_allocator{ASL_MOVE(allocator)}
+        : m_allocator{std::move(allocator)}
    {}

    explicit constexpr buffer(span<const T> s, Allocator allocator)
-        : m_allocator{ASL_MOVE(allocator)}
+        : m_allocator{std::move(allocator)}
    {
        copy_range(s);
    }
@ -241,10 +273,9 @@ public:
    }

    constexpr buffer(buffer&& other)
-        requires moveable<T>
-        : buffer(ASL_MOVE(other.m_allocator))
+        : buffer(std::move(other.m_allocator))
    {
-        move_from_other(ASL_MOVE(other), false);
+        move_from_other(std::move(other), false);
    }

    constexpr buffer& operator=(const buffer& other)
@ -256,10 +287,9 @@ public:
    }

    constexpr buffer& operator=(buffer&& other)
-        requires moveable<T>
    {
        if (&other == this) { return *this; }
-        move_from_other(ASL_MOVE(other), true);
+        move_from_other(std::move(other), true);
        return *this;
    }

@ -268,12 +298,22 @@ public:
        destroy();
    }

-    constexpr isize_t size() const
+    constexpr Allocator allocator_copy() const
+        requires copy_constructible<Allocator>
+    {
+        return m_allocator;
+    }
+
+    constexpr Allocator& allocator() { return m_allocator; }
+
+    [[nodiscard]] constexpr isize_t size() const
    {
        return decode_size(load_size_encoded());
    }

-    constexpr isize_t capacity() const
+    [[nodiscard]] constexpr bool is_empty() const { return size() == 0; }
+
+    [[nodiscard]] constexpr isize_t capacity() const
    {
        if constexpr (kInlineCapacity == 0)
        {
@ -287,7 +327,7 @@ public:

    void clear()
    {
-        isize_t current_size = size();
+        const isize_t current_size = size();
        if (current_size == 0) { return; }

        destroy_n(data(), current_size);
@ -311,12 +351,11 @@ public:
    void reserve_capacity(isize_t new_capacity)
    {
        ASL_ASSERT(new_capacity >= 0);
-        ASL_ASSERT_RELEASE(new_capacity <= 0x4000'0000'0000'0000);

        if (new_capacity <= capacity()) { return; }
        ASL_ASSERT(new_capacity > kInlineCapacity);

-        new_capacity = static_cast<isize_t>(round_up_pow2(static_cast<uint64_t>(new_capacity)));
+        new_capacity = static_cast<isize_t>(bit_ceil(static_cast<uint64_t>(new_capacity)));

        T* old_data = data();
        const isize_t old_capacity = capacity();
@ -328,12 +367,12 @@ public:

        if (currently_on_heap && trivially_move_constructible<T>)
        {
-            m_data = reinterpret_cast<T*>(m_allocator.realloc(m_data, old_layout, new_layout));
+            m_data = static_cast<T*>(m_allocator.realloc(m_data, old_layout, new_layout));
            m_capacity = new_capacity;
            return;
        }

-        T* new_data = reinterpret_cast<T*>(m_allocator.alloc(new_layout));
+        T* new_data = static_cast<T*>(m_allocator.alloc(new_layout));

        relocate_uninit_n(new_data, old_data, current_size);

@ -348,17 +387,16 @@ public:
    }

    constexpr void resize_uninit(isize_t new_size)
-        requires trivially_default_constructible<T> && trivially_destructible<T>
+        requires trivially_default_constructible<T>
    {
-        reserve_capacity(new_size);
-        set_size(new_size);
+        resize_uninit_inner(new_size);
    }

    constexpr void resize_zero(isize_t new_size)
-        requires trivially_default_constructible<T> && trivially_destructible<T>
+        requires trivially_default_constructible<T>
    {
-        isize_t old_size = size();
-        resize_uninit(new_size);
+        const isize_t old_size = size();
+        resize_uninit_inner(new_size);

        if (new_size > old_size)
        {
@ -369,7 +407,14 @@ public:
    void resize(isize_t new_size)
        requires default_constructible<T>
    {
-        resize_inner(new_size);
+        if constexpr (trivially_default_constructible<T>)
+        {
+            resize_zero(new_size);
+        }
+        else
+        {
+            resize_inner(new_size);
+        }
    }

    void resize(isize_t new_size, const T& value)
@ -380,63 +425,68 @@ public:
    constexpr T& push(auto&&... args)
        requires constructible_from<T, decltype(args)&&...>
    {
-        T* uninit = push_uninit();
-        T* init = construct_at<T>(uninit, ASL_FWD(args)...);
+        void* uninit = push_uninit();
+        T* init = construct_at<T>(uninit, std::forward<decltype(args)>(args)...);
        return *init;
    }

    auto data(this auto&& self)
    {
-        using return_type = un_ref_t<copy_cref_t<decltype(self), T>>*;
+        using return_type = as_ptr_t<copy_const_t<un_ref_t<decltype(self)>, T>>;
+        // NOLINTNEXTLINE(*-reinterpret-cast)
+        auto&& buffer = reinterpret_cast<copy_cref_t<decltype(self), class buffer>>(self);
        if constexpr (kInlineCapacity == 0)
        {
-            return return_type{ self.m_data };
+            return return_type{ buffer.m_data };
        }
        else
        {
-            return self.is_on_heap() ? return_type{ self.m_data } : reinterpret_cast<return_type>(&self);
+            return buffer.is_on_heap()
+                ? return_type{ buffer.m_data }
+                // NOLINTNEXTLINE(*-reinterpret-cast)
+                : std::launder(reinterpret_cast<return_type>(&buffer));
        }
    }

    constexpr auto begin(this auto&& self)
    {
-        using type = un_ref_t<copy_cref_t<decltype(self), T>>;
+        using type = copy_const_t<un_ref_t<decltype(self)>, T>;
        return contiguous_iterator<type>{self.data()};
    }

    constexpr auto end(this auto&& self)
    {
-        using type = un_ref_t<copy_cref_t<decltype(self), T>>;
+        using type = copy_const_t<un_ref_t<decltype(self)>, T>;
        return contiguous_iterator<type>{self.data() + self.size()};
    }

-    constexpr operator span<const T>() const // NOLINT(*-explicit-conversions)
+    constexpr operator span<const T>() const // NOLINT(*explicit*)
    {
        return as_span();
    }

-    constexpr operator span<T>() // NOLINT(*-explicit-conversions)
+    constexpr operator span<T>() // NOLINT(*explicit*)
    {
        return as_span();
    }

    constexpr auto as_span(this auto&& self)
    {
-        using type = un_ref_t<copy_cref_t<decltype(self), T>>;
+        using type = copy_const_t<un_ref_t<decltype(self)>, T>;
        return span<type>{self.data(), self.size()};
    }

    constexpr auto&& operator[](this auto&& self, isize_t i)
    {
-        ASL_ASSERT(i >= 0 && i <= self.size());
-        return ASL_FWD_LIKE(decltype(self), ASL_FWD(self).data()[i]);
+        ASL_ASSERT(i >= 0 && i < self.size());
+        return std::forward_like<decltype(self)>(std::forward<decltype(self)>(self).data()[i]);
    }

    template<typename H>
    requires hashable<T>
    friend H AslHashValue(H h, const buffer& b)
    {
-        return H::combine_contiguous(ASL_MOVE(h), b.as_span());
+        return H::combine_contiguous(std::move(h), b.as_span());
    }
 };

--- a/asl/containers/buffer_tests.cpp
+++ b/asl/containers/buffer_tests.cpp
@ -6,6 +6,7 @@

 #include "asl/testing/testing.hpp"
 #include "asl/tests/types.hpp"
+#include "asl/tests/counting_allocator.hpp"

 struct Big
 {
@ -14,6 +15,7 @@ struct Big

 static_assert(asl::buffer<int32_t>::kInlineCapacity == 5);
 static_assert(asl::buffer<int64_t>::kInlineCapacity == 2);
+static_assert(asl::buffer<void*>::kInlineCapacity == 2);
 static_assert(asl::buffer<char>::kInlineCapacity == 23);
 static_assert(asl::buffer<Big>::kInlineCapacity == 0);

@ -24,37 +26,12 @@ ASL_TEST(default_size)
    ASL_TEST_EXPECT(b1.capacity() == 5);
    ASL_TEST_EXPECT(static_cast<const void*>(b1.data()) == &b1);

-    asl::buffer<Big> b2;
+    const asl::buffer<Big> b2;
    ASL_TEST_EXPECT(b2.size() == 0);
    ASL_TEST_EXPECT(b2.capacity() == 0);
    ASL_TEST_EXPECT(b2.data() == nullptr);
 }

-struct CounterAllocator
-{
-    isize_t* count;
-
-    void* alloc(const asl::layout& layout) const
-    {
-        *count += 1;
-        return asl::GlobalHeap::alloc(layout);
-    }
-
-    void* realloc(void* ptr, const asl::layout& old, const asl::layout& new_layout) const
-    {
-        *count += 1;
-        return asl::GlobalHeap::realloc(ptr, old, new_layout);
-    }
-
-    static void dealloc(void* ptr, const asl::layout& layout)
-    {
-        asl::GlobalHeap::dealloc(ptr, layout);
-    }
-
-    constexpr bool operator==(const CounterAllocator&) const { return true; }
-};
-static_assert(asl::allocator<CounterAllocator>);
-
 struct IncompatibleAllocator
 {
    static void* alloc(const asl::layout& layout)
@ -76,35 +53,37 @@ struct IncompatibleAllocator
 };
 static_assert(asl::allocator<IncompatibleAllocator>);

+// NOLINTNEXTLINE(*-complexity)
 ASL_TEST(reserve_capacity)
 {
-    isize_t count = 0;
-    asl::buffer<int32_t, CounterAllocator> b(CounterAllocator{&count});
+    CountingAllocator::Stats stats;
+    asl::buffer<int32_t, CountingAllocator> b(CountingAllocator{&stats});
    ASL_TEST_EXPECT(b.size() == 0);
    ASL_TEST_EXPECT(b.capacity() == 5);
-    ASL_TEST_EXPECT(count == 0);
+    ASL_TEST_EXPECT(stats.any_alloc_count() == 0);

    b.reserve_capacity(4);
    ASL_TEST_EXPECT(b.size() == 0);
    ASL_TEST_EXPECT(b.capacity() == 5);
-    ASL_TEST_EXPECT(count == 0);
+    ASL_TEST_EXPECT(stats.any_alloc_count() == 0);

    b.reserve_capacity(12);
    ASL_TEST_EXPECT(b.size() == 0);
    ASL_TEST_EXPECT(b.capacity() >= 12);
-    ASL_TEST_EXPECT(count == 1);
+    ASL_TEST_EXPECT(stats.any_alloc_count() == 1);

    b.reserve_capacity(13);
    ASL_TEST_EXPECT(b.size() == 0);
    ASL_TEST_EXPECT(b.capacity() >= 13);
-    ASL_TEST_EXPECT(count == 1);
+    ASL_TEST_EXPECT(stats.any_alloc_count() == 1);

    b.reserve_capacity(130);
    ASL_TEST_EXPECT(b.size() == 0);
    ASL_TEST_EXPECT(b.capacity() >= 130);
-    ASL_TEST_EXPECT(count == 2);
+    ASL_TEST_EXPECT(stats.any_alloc_count() == 2);
 }

+// NOLINTNEXTLINE(*-complexity)
 ASL_TEST(push)
 {
    asl::buffer<int32_t> b;
@ -137,7 +116,7 @@ ASL_TEST(push)

 ASL_TEST(from_span)
 {
-    int data[] = {1, 2, 4, 8};
+    const int data[] = {1, 2, 4, 8};
    asl::buffer<int> b{data};

    ASL_TEST_EXPECT(b.size() == 4);
@ -156,13 +135,21 @@ struct MoveableType
    MoveableType(const MoveableType&) = delete;
    MoveableType(MoveableType&& other)  : moved{other.moved + 1}, value{other.value} {}
    MoveableType& operator=(const MoveableType&) = delete;
-    MoveableType& operator=(MoveableType&&) = delete;
+    MoveableType& operator=(MoveableType&& other)
+    {
+        if (this == &other) { return *this; }
+        moved = other.moved + 1;
+        value = other.value;
+        return *this;
+    }
+    ~MoveableType() = default;
 };
 static_assert(!asl::trivially_copy_constructible<MoveableType>);
 static_assert(!asl::trivially_move_constructible<MoveableType>);
 static_assert(!asl::copyable<MoveableType>);
-static_assert(asl::move_constructible<MoveableType>);
+static_assert(asl::moveable<MoveableType>);

+// NOLINTNEXTLINE(*-complexity)
 ASL_TEST(push_move)
 {
    asl::buffer<MoveableType> b;
@ -208,6 +195,30 @@ ASL_TEST(push_move)
    ASL_TEST_EXPECT(b[3].moved == 1);
    ASL_TEST_EXPECT(b[4].value == 4);
    ASL_TEST_EXPECT(b[4].moved == 0);
+
+    asl::buffer<MoveableType> b2 = std::move(b);
+    ASL_TEST_EXPECT(b2[0].value == 0);
+    ASL_TEST_EXPECT(b2[0].moved == 2);
+    ASL_TEST_EXPECT(b2[1].value == 1);
+    ASL_TEST_EXPECT(b2[1].moved == 2);
+    ASL_TEST_EXPECT(b2[2].value == 2);
+    ASL_TEST_EXPECT(b2[2].moved == 1);
+    ASL_TEST_EXPECT(b2[3].value == 3);
+    ASL_TEST_EXPECT(b2[3].moved == 1);
+    ASL_TEST_EXPECT(b2[4].value == 4);
+    ASL_TEST_EXPECT(b2[4].moved == 0);
+
+    b = std::move(b2);
+    ASL_TEST_EXPECT(b[0].value == 0);
+    ASL_TEST_EXPECT(b[0].moved == 2);
+    ASL_TEST_EXPECT(b[1].value == 1);
+    ASL_TEST_EXPECT(b[1].moved == 2);
+    ASL_TEST_EXPECT(b[2].value == 2);
+    ASL_TEST_EXPECT(b[2].moved == 1);
+    ASL_TEST_EXPECT(b[3].value == 3);
+    ASL_TEST_EXPECT(b[3].moved == 1);
+    ASL_TEST_EXPECT(b[4].value == 4);
+    ASL_TEST_EXPECT(b[4].moved == 0);
 }

 ASL_TEST(clear)
@ -275,14 +286,13 @@ ASL_TEST(move_construct_from_heap)
    buf.push(&d[2]);

    {
-        asl::buffer<DestructorObserver> buf2(ASL_MOVE(buf));
+        const asl::buffer<DestructorObserver> buf2(std::move(buf));
        ASL_TEST_EXPECT(buf2.size() == 3);
        ASL_TEST_EXPECT(d[0] == false);
        ASL_TEST_EXPECT(d[1] == false);
        ASL_TEST_EXPECT(d[2] == false);
    }

-    ASL_TEST_EXPECT(buf.size() == 0);
    ASL_TEST_EXPECT(d[0] == true);
    ASL_TEST_EXPECT(d[1] == true);
    ASL_TEST_EXPECT(d[2] == true);
@ -294,12 +304,11 @@ ASL_TEST(move_construct_inline_trivial)
    buf.push(1U);
    buf.push(2U);

-    asl::buffer<uint64_t> buf2(ASL_MOVE(buf));
+    asl::buffer<uint64_t> buf2(std::move(buf));
    ASL_TEST_EXPECT(buf2[0] == 1U);
    ASL_TEST_EXPECT(buf2[1] == 2U);

    ASL_TEST_EXPECT(buf2.size() == 2);
-    ASL_TEST_EXPECT(buf.size() == 0);
 }

 ASL_TEST(move_construct_from_inline_non_trivial)
@ -310,17 +319,17 @@ ASL_TEST(move_construct_from_inline_non_trivial)
    buf.push(&d[1]);

    {
-        asl::buffer<DestructorObserver> buf2(ASL_MOVE(buf));
+        const asl::buffer<DestructorObserver> buf2(std::move(buf));
        ASL_TEST_EXPECT(buf2.size() == 2);
        ASL_TEST_EXPECT(d[0] == false);
        ASL_TEST_EXPECT(d[1] == false);
    }

-    ASL_TEST_EXPECT(buf.size() == 0);
    ASL_TEST_EXPECT(d[0] == true);
    ASL_TEST_EXPECT(d[1] == true);
 }

+// NOLINTNEXTLINE(*-complexity)
 ASL_TEST(move_assign_from_heap)
 {
    bool d[6]{};
@ -344,9 +353,8 @@ ASL_TEST(move_assign_from_heap)
        ASL_TEST_EXPECT(d[4] == false);
        ASL_TEST_EXPECT(d[5] == false);

-        buf2 = ASL_MOVE(buf);
+        buf2 = std::move(buf);

-        ASL_TEST_EXPECT(buf.size() == 0);
        ASL_TEST_EXPECT(buf2.size() == 3);

        ASL_TEST_EXPECT(d[0] == false);
@ -367,24 +375,23 @@ ASL_TEST(move_assign_from_heap)

 ASL_TEST(move_assign_trivial_heap_to_inline)
 {
-    isize_t alloc_count = 0;
-    asl::buffer<int64_t, CounterAllocator> buf{CounterAllocator{&alloc_count}};
-    asl::buffer<int64_t, CounterAllocator> buf2{CounterAllocator{&alloc_count}};
+    CountingAllocator::Stats stats;
+    asl::buffer<int64_t, CountingAllocator> buf{CountingAllocator{&stats}};
+    asl::buffer<int64_t, CountingAllocator> buf2{CountingAllocator{&stats}};

    buf.push(1);
    buf.push(2);
-    ASL_TEST_EXPECT(alloc_count == 0);
+    ASL_TEST_EXPECT(stats.any_alloc_count() == 0);

    buf2.push(3);
    buf2.push(4);
    buf2.push(5);
-    ASL_TEST_EXPECT(alloc_count == 1);
+    ASL_TEST_EXPECT(stats.any_alloc_count() == 1);

-    buf = ASL_MOVE(buf2);
-    ASL_TEST_EXPECT(alloc_count == 1);
+    buf = std::move(buf2);
+    ASL_TEST_EXPECT(stats.any_alloc_count() == 1);

    ASL_TEST_EXPECT(buf.size() == 3);
-    ASL_TEST_EXPECT(buf2.size() == 0);
    ASL_TEST_EXPECT(buf[0] == 3);
    ASL_TEST_EXPECT(buf[1] == 4);
    ASL_TEST_EXPECT(buf[2] == 5);
@ -392,28 +399,28 @@ ASL_TEST(move_assign_trivial_heap_to_inline)

 ASL_TEST(move_assign_trivial_inline_to_heap)
 {
-    isize_t alloc_count = 0;
-    asl::buffer<int64_t, CounterAllocator> buf{CounterAllocator{&alloc_count}};
-    asl::buffer<int64_t, CounterAllocator> buf2{CounterAllocator{&alloc_count}};
+    CountingAllocator::Stats stats;
+    asl::buffer<int64_t, CountingAllocator> buf{CountingAllocator{&stats}};
+    asl::buffer<int64_t, CountingAllocator> buf2{CountingAllocator{&stats}};

    buf.push(1);
    buf.push(2);
-    ASL_TEST_EXPECT(alloc_count == 0);
+    ASL_TEST_EXPECT(stats.any_alloc_count() == 0);

    buf2.push(3);
    buf2.push(4);
    buf2.push(5);
-    ASL_TEST_EXPECT(alloc_count == 1);
+    ASL_TEST_EXPECT(stats.any_alloc_count() == 1);

-    buf2 = ASL_MOVE(buf);
-    ASL_TEST_EXPECT(alloc_count == 1);
+    buf2 = std::move(buf);
+    ASL_TEST_EXPECT(stats.any_alloc_count() == 1);

-    ASL_TEST_EXPECT(buf.size() == 0);
    ASL_TEST_EXPECT(buf2.size() == 2);
    ASL_TEST_EXPECT(buf2[0] == 1);
    ASL_TEST_EXPECT(buf2[1] == 2);
 }

+// NOLINTNEXTLINE(*-complexity)
 ASL_TEST(move_assign_inline_to_heap)
 {
    bool d[6]{};
@ -430,26 +437,26 @@ ASL_TEST(move_assign_inline_to_heap)
        buf2.push(&d[4]);
        buf2.push(&d[5]);

-        buf2 = ASL_MOVE(buf);
+        buf2 = std::move(buf);

-        ASL_TEST_EXPECT(buf.size() == 0);
        ASL_TEST_EXPECT(buf2.size() == 2);
        ASL_TEST_EXPECT(d[0] == false);
        ASL_TEST_EXPECT(d[1] == false);
-        ASL_TEST_EXPECT(d[2] == false); // moved but not destroyed
-        ASL_TEST_EXPECT(d[3] == false); // moved but not destroyed
+        ASL_TEST_EXPECT(d[2] == true);
+        ASL_TEST_EXPECT(d[3] == true);
        ASL_TEST_EXPECT(d[4] == true);
        ASL_TEST_EXPECT(d[5] == true);
    }

    ASL_TEST_EXPECT(d[0] == true);
    ASL_TEST_EXPECT(d[1] == true);
-    ASL_TEST_EXPECT(d[2] == false); // moved but not destroyed
-    ASL_TEST_EXPECT(d[3] == false); // moved but not destroyed
+    ASL_TEST_EXPECT(d[2] == true);
+    ASL_TEST_EXPECT(d[3] == true);
    ASL_TEST_EXPECT(d[4] == true);
    ASL_TEST_EXPECT(d[5] == true);
 }

+// NOLINTNEXTLINE(*-complexity)
 ASL_TEST(move_assign_from_inline_incompatible_allocator)
 {
    bool d[6]{};
@ -466,9 +473,8 @@ ASL_TEST(move_assign_from_inline_incompatible_allocator)
        buf2.push(&d[4]);
        buf2.push(&d[5]);

-        buf2 = ASL_MOVE(buf);
+        buf2 = std::move(buf);

-        ASL_TEST_EXPECT(buf.size() == 0);
        ASL_TEST_EXPECT(buf2.size() == 2);
        ASL_TEST_EXPECT(d[0] == false);
        ASL_TEST_EXPECT(d[1] == false);
@ -605,3 +611,6 @@ ASL_TEST(resize_zero)
    }
 }

+static_assert(asl::same_as<decltype(asl::declval<asl::buffer<int>>().data()), int*>);
+static_assert(asl::same_as<decltype(asl::declval<const asl::buffer<int>>().data()), const int*>);
+
--- a/asl/containers/chunked_buffer.hpp
+++ b/asl/containers/chunked_buffer.hpp
@ -0,0 +1,405 @@
+// Copyright 2025 Steven Le Rouzic
+//
+// SPDX-License-Identifier: BSD-3-Clause
+
+#pragma once
+
+#include "asl/base/utility.hpp"
+#include "asl/base/assert.hpp"
+#include "asl/base/numeric.hpp"
+#include "asl/containers/buffer.hpp"
+#include "asl/memory/allocator.hpp"
+#include "asl/types/array.hpp"
+#include "asl/types/maybe_uninit.hpp"
+
+namespace asl
+{
+
+template<
+    is_object T,
+    isize_t kChunkSize,
+    allocator Allocator = DefaultAllocator>
+class chunked_buffer
+{
+    static_assert(kChunkSize > 0 && is_pow2(kChunkSize));
+
+    using Chunk = array<maybe_uninit<T>, kChunkSize>;
+
+    static constexpr isize_t chunk_index(isize_t i)
+    {
+        static constexpr int kChunkSizeLog2 = countr_zero(uint64_t{kChunkSize});
+        return i >> kChunkSizeLog2;
+    }
+
+    static constexpr isize_t index_in_chunk(isize_t i)
+    {
+        static constexpr isize_t kMask = kChunkSize - 1;
+        return i & kMask;
+    }
+
+    struct PerChunkIterator
+    {
+        isize_t from_chunk;
+        isize_t to_chunk;
+
+        isize_t from_index_in_chunk;
+        isize_t to_index_in_chunk;
+
+        [[nodiscard]] constexpr bool has_more() const
+        {
+            return from_chunk <= to_chunk;
+        }
+
+        void advance()
+        {
+            from_chunk += 1;
+            from_index_in_chunk = 0;
+        }
+
+        [[nodiscard]] constexpr isize_t chunk() const { return from_chunk; }
+
+        span<maybe_uninit<T>> make_span(Chunk& chunk) const
+        {
+            isize_t from = from_index_in_chunk;
+            isize_t to = (from_chunk == to_chunk) ? to_index_in_chunk : kChunkSize - 1;
+            return chunk.as_span().subspan(from, to - from + 1);
+        }
+    };
+
+    PerChunkIterator make_index_iterator(isize_t from, isize_t to)
+    {
+        return PerChunkIterator {
+            chunk_index(from), chunk_index(to),
+            index_in_chunk(from), index_in_chunk(to)
+        };
+    }
+
+    buffer<Chunk*, Allocator>    m_chunks;
+    isize_t                      m_size{};
+
+    void resize_uninit_inner(isize_t new_size)
+    {
+        ASL_ASSERT(new_size >= 0);
+
+        if constexpr (!trivially_destructible<T>)
+        {
+            const isize_t old_size = size();
+            if (new_size < old_size)
+            {
+                for (PerChunkIterator it = make_index_iterator(new_size, old_size - 1);
+                    it.has_more();
+                    it.advance())
+                {
+                    auto span = it.make_span(*m_chunks[it.chunk()]);
+                    for (auto& el: span)
+                    {
+                        el.destroy_unsafe();
+                    }
+                }
+            }
+        }
+
+        reserve_capacity(new_size);
+        m_size = new_size;
+    }
+
+    template<typename... Args>
+    void resize_construct(isize_t new_size, Args&&... args)
+        requires constructible_from<T, Args&&...>
+    {
+        const isize_t old_size = m_size;
+        resize_uninit_inner(new_size);
+
+        if (new_size > old_size)
+        {
+            for (PerChunkIterator it = make_index_iterator(old_size, new_size - 1);
+                it.has_more();
+                it.advance())
+            {
+                auto span = it.make_span(*m_chunks[it.chunk()]);
+                for (auto& uninit: span)
+                {
+                    uninit.construct_unsafe(std::forward<Args>(args)...);
+                }
+            }
+        }
+    }
+
+    void copy_from(const chunked_buffer& other)
+        requires copyable<T>
+    {
+        const isize_t this_size = size();
+        isize_t to_copy_assign = asl::min(other.size(), this_size);
+
+        resize_uninit_inner(other.size());
+
+        for (PerChunkIterator it = make_index_iterator(0, to_copy_assign - 1);
+            it.has_more();
+            it.advance())
+        {
+            auto to_span = it.make_span(*m_chunks[it.chunk()]);
+            auto from_span = it.make_span(*other.m_chunks[it.chunk()]);
+
+            copy_assign_n(
+                reinterpret_cast<T*>(to_span.data()), // NOLINT(*-reinterpret-cast)
+                reinterpret_cast<const T*>(from_span.data()), // NOLINT(*-reinterpret-cast)
+                to_span.size());
+        }
+
+        if (other.size() > this_size)
+        {
+            for (PerChunkIterator it = make_index_iterator(to_copy_assign, other.size() - 1);
+                it.has_more();
+                it.advance())
+            {
+                auto to_span = it.make_span(*m_chunks[it.chunk()]);
+                auto from_span = it.make_span(*other.m_chunks[it.chunk()]);
+
+                copy_uninit_n(
+                    reinterpret_cast<T*>(to_span.data()), // NOLINT(*-reinterpret-cast)
+                    reinterpret_cast<const T*>(from_span.data()), // NOLINT(*-reinterpret-cast)
+                    to_span.size());
+            }
+        }
+
+        ASL_ASSERT(size() == other.size());
+    }
+
+public:
+    constexpr chunked_buffer()
+        requires default_constructible<Allocator>
+        = default;
+
+    explicit constexpr chunked_buffer(Allocator allocator)
+        : m_chunks{std::move(allocator)}
+    {}
+
+    constexpr chunked_buffer(const chunked_buffer& other)
+        requires copyable<T> && copy_constructible<Allocator>
+        : m_chunks{other.m_chunks.allocator_copy()}
+    {
+        copy_from(other);
+    }
+
+    constexpr chunked_buffer(chunked_buffer&& other)
+        : m_chunks{std::move(other.m_chunks)}
+        , m_size{asl::exchange(other.m_size, 0)}
+    {
+        ASL_ASSERT(other.m_chunks.size() == 0);
+    }
+
+    constexpr chunked_buffer& operator=(const chunked_buffer& other)
+        requires copyable<T>
+    {
+        if (&other == this) { return *this; }
+        copy_from(other);
+        return *this;
+    }
+
+    constexpr chunked_buffer& operator=(chunked_buffer&& other)
+    {
+        if (&other == this) { return *this; }
+        destroy();
+        m_chunks = std::move(other.m_chunks);
+        m_size = asl::exchange(other.m_size, 0);
+        ASL_ASSERT(other.m_chunks.size() == 0);
+        return *this;
+    }
+
+    ~chunked_buffer()
+    {
+        destroy();
+    }
+
+    void clear()
+    {
+        if constexpr (trivially_destructible<T>)
+        {
+            m_size = 0;
+        }
+        else if (m_size > 0)
+        {
+            resize_uninit_inner(0);
+            ASL_ASSERT(m_size == 0);
+        }
+    }
+
+    void destroy()
+    {
+        clear();
+        ASL_ASSERT(size() == 0);
+
+        for (Chunk* chunk:  m_chunks)
+        {
+            alloc_delete(m_chunks.allocator(), chunk);
+        }
+
+        m_chunks.destroy();
+    }
+
+    [[nodiscard]] constexpr isize_t size() const { return m_size; }
+
+    [[nodiscard]] constexpr bool is_empty() const { return size() == 0; }
+
+    [[nodiscard]] constexpr isize_t capacity() const
+    {
+        return m_chunks.size() * kChunkSize;
+    }
+
+    constexpr auto&& operator[](this auto&& self, isize_t i)
+    {
+        ASL_ASSERT(i >= 0 && i < self.m_size);
+        return std::forward_like<decltype(self)>(
+            (*std::forward<decltype(self)>(self).m_chunks[chunk_index(i)])
+                [index_in_chunk(i)].as_init_unsafe()
+        );
+    }
+
+    constexpr T& push(auto&&... args)
+        requires constructible_from<T, decltype(args)&&...>
+    {
+        const isize_t chunk = chunk_index(m_size);
+        const isize_t in_chunk = index_in_chunk(m_size);
+
+        if (m_size == capacity())
+        {
+            resize_uninit_inner(m_size + 1);
+        }
+        else
+        {
+            m_size += 1;
+        }
+
+        void* uninit = &(*m_chunks[chunk])[in_chunk];
+        return *construct_at<T>(uninit, std::forward<decltype(args)>(args)...);
+    }
+
+    void reserve_capacity(isize_t new_capacity)
+    {
+        new_capacity = round_up_pow2(new_capacity, kChunkSize);
+        if (new_capacity <= capacity()) { return; }
+
+        const isize_t required_chunks = new_capacity / kChunkSize;
+        const isize_t additional_chunks = required_chunks - m_chunks.size();
+        ASL_ASSERT(additional_chunks > 0);
+
+        m_chunks.reserve_capacity(required_chunks);
+        for (isize_t i = 0; i < additional_chunks; ++i)
+        {
+            // @Todo(C++26) _unsafe shouldn't be needed with trivial unions
+            auto* chunk = alloc_uninit_unsafe<Chunk>(m_chunks.allocator());
+            m_chunks.push(chunk);
+        }
+    }
+
+    void resize(isize_t new_size)
+        requires default_constructible<T>
+    {
+        if constexpr (trivially_default_constructible<T>)
+        {
+            resize_zero(new_size);
+        }
+        else
+        {
+            resize_construct(new_size);
+        }
+    }
+
+    void resize(isize_t new_size, const T& value)
+        requires copy_constructible<T>
+    {
+        resize_construct(new_size, value);
+    }
+
+    void resize_zero(isize_t new_size)
+        requires trivially_default_constructible<T>
+    {
+        const isize_t old_size = m_size;
+        resize_uninit_inner(new_size);
+
+        if (new_size > old_size)
+        {
+            for (PerChunkIterator it = make_index_iterator(old_size, new_size - 1);
+                it.has_more();
+                it.advance())
+            {
+                auto span = it.make_span(*m_chunks[it.chunk()]);
+                asl::memzero(span.data(), span.size_bytes());
+            }
+        }
+    }
+
+    void resize_uninit(isize_t new_size)
+        requires trivially_default_constructible<T>
+    {
+        resize_uninit_inner(new_size);
+    }
+
+    void pop()
+    {
+        ASL_ASSERT(size() > 0);
+        resize_uninit_inner(size() - 1);
+    }
+
+    template<typename Chunk>
+    class generic_iterator
+    {
+        isize_t     m_index;
+        span<Chunk> m_chunks;
+
+    public:
+        constexpr generic_iterator(isize_t index, span<Chunk> chunks)
+            : m_index{index}
+            , m_chunks{chunks}
+        {}
+
+        constexpr generic_iterator& operator++()
+        {
+            m_index += 1;
+            return *this;
+        }
+
+        constexpr generic_iterator operator++(int)
+        {
+            auto tmp = *this;
+            m_index += 1;
+            return tmp;
+        }
+
+        constexpr bool operator==(this generic_iterator self, generic_iterator other)
+        {
+            ASL_ASSERT(self.m_chunks.data() == other.m_chunks.data());
+            return self.m_index == other.m_index;
+        }
+
+        constexpr auto& operator*(this generic_iterator self)
+        {
+            ASL_ASSERT(self.m_index >= 0);
+            return (*self.m_chunks[chunk_index(self.m_index)])[index_in_chunk(self.m_index)].as_init_unsafe();
+        }
+
+        constexpr auto* operator->(this generic_iterator self)
+        {
+            return &*self;
+        }
+    };
+
+    using iterator       = generic_iterator<Chunk*>;
+    using const_iterator = generic_iterator<const Chunk* const>;
+
+    constexpr iterator begin() { return iterator{0, m_chunks}; }
+    constexpr iterator end()   { return iterator{m_size, m_chunks}; }
+
+    constexpr const_iterator begin() const
+    {
+        return const_iterator{0, {m_chunks.data(), m_chunks.size()}};
+    }
+
+    constexpr const_iterator end() const
+    {
+        return const_iterator{m_size, {m_chunks.data(), m_chunks.size()}};
+    }
+};
+
+} // namespace asl
+
--- a/asl/containers/chunked_buffer_tests.cpp
+++ b/asl/containers/chunked_buffer_tests.cpp
@ -0,0 +1,377 @@
+// Copyright 2025 Steven Le Rouzic
+//
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include "asl/testing/testing.hpp"
+#include "asl/tests/types.hpp"
+#include "asl/tests/counting_allocator.hpp"
+#include "asl/containers/chunked_buffer.hpp"
+
+static_assert(asl::moveable<asl::chunked_buffer<int, 8>>);
+static_assert(asl::moveable<asl::chunked_buffer<Copyable, 8>>);
+static_assert(asl::moveable<asl::chunked_buffer<MoveableOnly, 8>>);
+static_assert(asl::moveable<asl::chunked_buffer<Pinned, 8>>);
+
+static_assert(asl::copyable<asl::chunked_buffer<int, 8>>);
+static_assert(asl::copyable<asl::chunked_buffer<Copyable, 8>>);
+static_assert(!asl::copyable<asl::chunked_buffer<MoveableOnly, 8>>);
+static_assert(!asl::copyable<asl::chunked_buffer<Pinned, 8>>);
+
+ASL_TEST(reserve)
+{
+    asl::chunked_buffer<int, 16> b;
+    ASL_TEST_EXPECT(b.capacity() == 0);
+    ASL_TEST_EXPECT(b.size() == 0);
+
+    b.reserve_capacity(1);
+    ASL_TEST_EXPECT(b.capacity() == 16);
+    ASL_TEST_EXPECT(b.size() == 0);
+
+    b.reserve_capacity(5);
+    ASL_TEST_EXPECT(b.capacity() == 16);
+    ASL_TEST_EXPECT(b.size() == 0);
+
+    b.reserve_capacity(16);
+    ASL_TEST_EXPECT(b.capacity() == 16);
+    ASL_TEST_EXPECT(b.size() == 0);
+
+    b.reserve_capacity(35);
+    ASL_TEST_EXPECT(b.capacity() == 48);
+    ASL_TEST_EXPECT(b.size() == 0);
+
+    b.reserve_capacity(12);
+    ASL_TEST_EXPECT(b.capacity() == 48);
+    ASL_TEST_EXPECT(b.size() == 0);
+}
+
+ASL_TEST(resize_uninit)
+{
+    asl::chunked_buffer<int, 16> b;
+    ASL_TEST_EXPECT(b.capacity() == 0);
+    ASL_TEST_EXPECT(b.size() == 0);
+
+    b.resize_uninit(1);
+    ASL_TEST_EXPECT(b.capacity() == 16);
+    ASL_TEST_EXPECT(b.size() == 1);
+
+    b.resize_uninit(5);
+    ASL_TEST_EXPECT(b.capacity() == 16);
+    ASL_TEST_EXPECT(b.size() == 5);
+
+    b.resize_uninit(16);
+    ASL_TEST_EXPECT(b.capacity() == 16);
+    ASL_TEST_EXPECT(b.size() == 16);
+
+    b.resize_uninit(35);
+    ASL_TEST_EXPECT(b.capacity() == 48);
+    ASL_TEST_EXPECT(b.size() == 35);
+
+    b.resize_uninit(12);
+    ASL_TEST_EXPECT(b.capacity() == 48);
+    ASL_TEST_EXPECT(b.size() == 12);
+}
+
+ASL_TEST(resize_zero)
+{
+    asl::chunked_buffer<int, 4> b;
+    ASL_TEST_EXPECT(b.capacity() == 0);
+    ASL_TEST_EXPECT(b.size() == 0);
+
+    b.resize_zero(2);
+    for (isize_t i = 0; i < 2; ++i)
+    {
+        ASL_TEST_EXPECT(b[i] == 0);
+    }
+
+    b.resize_zero(18);
+    for (isize_t i = 0; i < 18; ++i)
+    {
+        ASL_TEST_EXPECT(b[i] == 0);
+    }
+}
+
+ASL_TEST(resize)
+{
+    asl::chunked_buffer<int, 4> b;
+    ASL_TEST_EXPECT(b.capacity() == 0);
+    ASL_TEST_EXPECT(b.size() == 0);
+
+    b.resize(10);
+    for (isize_t i = 0; i < 10; ++i)
+    {
+        ASL_TEST_EXPECT(b[i] == 0);
+    }
+
+    b.resize(20, 8);
+    for (isize_t i = 0; i < 10; ++i)
+    {
+        ASL_TEST_EXPECT(b[i] == 0);
+    }
+
+    for (isize_t i = 10; i < 20; ++i)
+    {
+        ASL_TEST_EXPECT(b[i] == 8);
+    }
+}
+
+ASL_TEST(push)
+{
+    asl::chunked_buffer<int, 4> b;
+
+    for (int i = 0; i < 100; ++i)
+    {
+        b.push(i);
+    }
+
+    for (int i = 0; i < 100; ++i)
+    {
+        ASL_TEST_EXPECT(b[i] == i);
+    }
+
+    b.resize(1000);
+    for (int i = 0; i < 100; ++i)
+    {
+        ASL_TEST_EXPECT(b[i] == i);
+    }
+}
+
+ASL_TEST(pop)
+{
+    asl::chunked_buffer<int, 2> b;
+
+    for (int i = 0; i < 8; ++i)
+    {
+        b.push(i);
+    }
+    ASL_TEST_EXPECT(b.size() == 8);
+
+    b.pop();
+    ASL_TEST_EXPECT(b.size() == 7);
+    for (int i = 0; i < 7; ++i)
+    {
+        ASL_TEST_EXPECT(b[i] == i);
+    }
+}
+
+ASL_TEST(pop_destruct)
+{
+    bool d[3]{};
+    asl::chunked_buffer<DestructorObserver, 16> b;
+
+    b.push(&d[0]);
+    b.push(&d[1]);
+    b.push(&d[2]);
+
+    ASL_TEST_EXPECT(!d[0]);
+    ASL_TEST_EXPECT(!d[1]);
+    ASL_TEST_EXPECT(!d[2]);
+
+    b.pop();
+    ASL_TEST_EXPECT(!d[0]);
+    ASL_TEST_EXPECT(!d[1]);
+    ASL_TEST_EXPECT(d[2]);
+
+    b.pop();
+    ASL_TEST_EXPECT(!d[0]);
+    ASL_TEST_EXPECT(d[1]);
+    ASL_TEST_EXPECT(d[2]);
+}
+
+ASL_TEST(clear_destroy)
+{
+    bool destroyed[5]{};
+    asl::chunked_buffer<DestructorObserver, 2> buf;
+
+    for (bool& d: destroyed)
+    {
+        buf.push(&d); // NOLINT
+    }
+
+    for (const bool d: destroyed)
+    {
+        ASL_TEST_EXPECT(!d);
+    }
+
+    buf.clear();
+
+    for (const bool d: destroyed)
+    {
+        ASL_TEST_EXPECT(d);
+    }
+}
+
+ASL_TEST(alloc_count) // NOLINT
+{
+    CountingAllocator::Stats stats;
+    asl::chunked_buffer<int, 4, CountingAllocator> buf{CountingAllocator{&stats}};
+
+    ASL_TEST_EXPECT(stats.alive_bytes == 0);
+    ASL_TEST_EXPECT(stats.alloc_count == 0);
+    ASL_TEST_EXPECT(stats.dealloc_count == 0);
+    ASL_TEST_EXPECT(stats.any_alloc_count() == 0);
+
+    buf.push(1);
+    ASL_TEST_EXPECT(stats.alive_bytes > 0);
+    ASL_TEST_EXPECT(stats.dealloc_count == 0);
+    ASL_TEST_EXPECT(stats.any_alloc_count() == 1);
+
+    buf.push(2);
+    buf.push(3);
+    buf.push(4);
+    ASL_TEST_EXPECT(stats.alive_bytes > 0);
+    ASL_TEST_EXPECT(stats.dealloc_count == 0);
+    ASL_TEST_EXPECT(stats.any_alloc_count() == 1);
+
+    buf.push(5);
+    buf.push(6);
+    ASL_TEST_EXPECT(stats.alive_bytes > 0);
+    ASL_TEST_EXPECT(stats.dealloc_count == 0);
+    ASL_TEST_EXPECT(stats.any_alloc_count() == 2);
+
+    buf.resize(8, 8);
+    ASL_TEST_EXPECT(stats.alive_bytes > 0);
+    ASL_TEST_EXPECT(stats.dealloc_count == 0);
+    ASL_TEST_EXPECT(stats.any_alloc_count() == 2);
+
+    buf.resize(32, 8);
+    ASL_TEST_EXPECT(stats.alive_bytes > 0);
+    ASL_TEST_EXPECT(stats.dealloc_count == 0);
+    ASL_TEST_EXPECT(stats.any_alloc_count() == 9);
+
+    buf.resize(16, 0);
+    ASL_TEST_EXPECT(stats.alive_bytes > 0);
+    ASL_TEST_EXPECT(stats.dealloc_count == 0);
+    ASL_TEST_EXPECT(stats.any_alloc_count() == 9);
+
+    buf.clear();
+    ASL_TEST_EXPECT(stats.alive_bytes > 0);
+    ASL_TEST_EXPECT(stats.dealloc_count == 0);
+    ASL_TEST_EXPECT(stats.any_alloc_count() == 9);
+
+    buf.destroy();
+    ASL_TEST_EXPECT(stats.alive_bytes == 0);
+    ASL_TEST_EXPECT(stats.dealloc_count == 9);
+    ASL_TEST_EXPECT(stats.any_alloc_count() == 9);
+}
+
+ASL_TEST(move)
+{
+    bool destroyed[5]{};
+
+    {
+        asl::chunked_buffer<DestructorObserver, 2> buf;
+
+        for (bool& d: destroyed)
+        {
+            buf.push(&d); // NOLINT
+        }
+
+        for (const bool d: destroyed)
+        {
+            ASL_TEST_EXPECT(!d);
+        }
+
+        asl::chunked_buffer<DestructorObserver, 2> buf2 = std::move(buf);
+
+        for (const bool d: destroyed)
+        {
+            ASL_TEST_EXPECT(!d);
+        }
+
+        buf = std::move(buf2);
+        buf2.destroy();
+
+        for (const bool d: destroyed)
+        {
+            ASL_TEST_EXPECT(!d);
+        }
+    }
+
+    for (const bool d: destroyed)
+    {
+        ASL_TEST_EXPECT(d);
+    }
+}
+
+ASL_TEST(copy) // NOLINT
+{
+    asl::chunked_buffer<int, 4> buf;
+    for (int i = 0; i < 10; ++i) { buf.push(i); }
+
+    asl::chunked_buffer<int, 4> buf2 = buf;
+
+    ASL_TEST_EXPECT(buf.size() == 10);
+    ASL_TEST_EXPECT(buf2.size() == 10);
+    for (int i = 0; i < 10; ++i)
+    {
+        ASL_TEST_EXPECT(buf[i] == i);
+        ASL_TEST_EXPECT(buf2[i] == i);
+    }
+
+    buf2.resize(5);
+    buf = buf2;
+
+    ASL_TEST_EXPECT(buf.size() == 5);
+    ASL_TEST_EXPECT(buf2.size() == 5);
+    for (int i = 0; i < 5; ++i)
+    {
+        ASL_TEST_EXPECT(buf[i] == i);
+        ASL_TEST_EXPECT(buf2[i] == i);
+    }
+
+    buf.clear();
+    buf.resize(80, 12);
+    buf2 = buf;
+    ASL_TEST_EXPECT(buf.size() == 80);
+    ASL_TEST_EXPECT(buf2.size() == 80);
+    for (int i = 0; i < 80; ++i)
+    {
+        ASL_TEST_EXPECT(buf[i] == 12);
+        ASL_TEST_EXPECT(buf2[i] == 12);
+    }
+}
+
+ASL_TEST(iterator)
+{
+    asl::chunked_buffer<int, 4> buf;
+    for (int i = 0; i < 30; ++i) { buf.push(100 + i); }
+
+    auto it = buf.begin();
+    auto end = buf.end();
+    for (int i = 0; i < 30; ++i)
+    {
+        ASL_TEST_ASSERT(it != end);
+        ASL_TEST_EXPECT(*it == 100 + i);
+        it++;
+    }
+    ASL_TEST_EXPECT(it == end);
+
+    static_assert(asl::same_as<decltype(*it), int&>);
+
+    asl::chunked_buffer<int, 8> buf2;
+    ASL_TEST_EXPECT(buf2.begin() == buf2.end());
+}
+
+ASL_TEST(const_iterator)
+{
+    asl::chunked_buffer<int, 4> buf_value;
+    for (int i = 0; i < 30; ++i) { buf_value.push(100 + i); }
+
+    const auto& buf = buf_value;
+
+    auto it = buf.begin();
+    auto end = buf.end();
+    for (int i = 0; i < 30; ++i)
+    {
+        ASL_TEST_ASSERT(it != end);
+        ASL_TEST_EXPECT(*it == 100 + i);
+        ++it;
+    }
+    ASL_TEST_EXPECT(it == end);
+
+    static_assert(asl::same_as<decltype(*it), const int&>);
+
+    asl::chunked_buffer<int, 8> buf2;
+    ASL_TEST_EXPECT(buf2.begin() == buf2.end());
+}
+
--- a/asl/containers/hash_map.hpp
+++ b/asl/containers/hash_map.hpp
@ -77,25 +77,17 @@ public:
    constexpr hash_map() requires default_constructible<Allocator> = default;

    explicit constexpr hash_map(Allocator allocator)
-        : Base{ASL_MOVE(allocator)}
+        : Base{std::move(allocator)}
    {}

-    hash_map(const hash_map&) requires copyable<K> && copyable<V> = default;
-
-    hash_map& operator=(const hash_map&) requires copyable<K> && copyable<V> = default;
-
-    hash_map(hash_map&&) = default;
-
-    hash_map& operator=(hash_map&&) = default;
-
-    ~hash_map() = default;
-
    using Base::destroy;

    using Base::clear;

    using Base::size;

+    using Base::is_empty;
+
    using Base::remove;

    using Base::contains;
@ -122,7 +114,7 @@ public:
            {
                ASL_ASSERT((Base::m_tags[result.first_available_index] & Base::kHasValue) == 0);

-                Base::m_values[result.first_available_index].construct_unsafe(ASL_MOVE(Base::m_values[result.already_present_index].as_init_unsafe()));
+                Base::m_values[result.first_available_index].construct_unsafe(std::move(Base::m_values[result.already_present_index].as_init_unsafe()));
                Base::m_values[result.already_present_index].destroy_unsafe();

                Base::m_tags[result.first_available_index] = result.tag;
@ -133,17 +125,17 @@ public:

            if constexpr (sizeof...(Args1) == 0 && assignable_from<V&, Arg0&&>)
            {
-                Base::m_values[result.first_available_index].as_init_unsafe().value = ASL_FWD(arg0);
+                Base::m_values[result.first_available_index].as_init_unsafe().value = std::forward<Arg0>(arg0);
            }
            else
            {
-                Base::m_values[result.first_available_index].as_init_unsafe().value = ASL_MOVE(V{ASL_FWD(arg0), ASL_FWD(args1)...});
+                Base::m_values[result.first_available_index].as_init_unsafe().value = std::move(V{std::forward<Arg0>(arg0), std::forward<Args1>(args1)...});
            }
        }
        else
        {
            ASL_ASSERT((Base::m_tags[result.first_available_index] & Base::kHasValue) == 0);
-            Base::m_values[result.first_available_index].construct_unsafe(ASL_FWD(key), V{ASL_FWD(arg0), ASL_FWD(args1)...});
+            Base::m_values[result.first_available_index].construct_unsafe(std::forward<U>(key), V{std::forward<Arg0>(arg0), std::forward<Args1>(args1)...});
            Base::m_tags[result.first_available_index] = result.tag;
            Base::m_size += 1;
        }
@ -155,7 +147,7 @@ public:
    auto get(this auto&& self, const U& value)
        requires key_hasher<KeyHasher, U> && key_comparator<KeyComparator, K, U>
    {
-        using return_type = un_ref_t<copy_cref_t<decltype(self), V>>*;
+        using return_type = copy_const_t<un_ref_t<decltype(self)>, V>*;
        isize_t index = self.find_slot_lookup(value);
        if (index >= 0)
        {
--- a/asl/containers/hash_map_tests.cpp
+++ b/asl/containers/hash_map_tests.cpp
@ -5,6 +5,7 @@
 #include "asl/testing/testing.hpp"
 #include "asl/containers/hash_map.hpp"

+// NOLINTNEXTLINE(*-complexity)
 ASL_TEST(default)
 {
    asl::hash_map<int, int> map;
--- a/asl/containers/hash_set.hpp
+++ b/asl/containers/hash_set.hpp
@ -7,6 +7,8 @@
 #include "asl/base/annotations.hpp"
 #include "asl/base/utility.hpp"
 #include "asl/base/meta.hpp"
+#include "asl/base/bit.hpp"
+#include "asl/base/numeric.hpp"
 #include "asl/memory/allocator.hpp"
 #include "asl/memory/memory.hpp"
 #include "asl/types/maybe_uninit.hpp"
@ -72,10 +74,10 @@ protected:

    ASL_NO_UNIQUE_ADDRESS Allocator m_allocator;

-    constexpr isize_t max_size() const
+    [[nodiscard]] constexpr isize_t max_size() const
    {
        // Max load factor is 75%
-        return (m_capacity >> 1) + (m_capacity >> 2);
+        return (m_capacity >> 1) + (m_capacity >> 2); // NOLINT(*-signed-bitwise)
    }

    static isize_t size_to_capacity(isize_t size)
@ -83,7 +85,7 @@ protected:
        ASL_ASSERT(size > 0);
        return max<isize_t>(
            kMinCapacity,
-            static_cast<isize_t>(round_up_pow2((static_cast<uint64_t>(size) * 4 + 2) / 3)));
+            static_cast<isize_t>(bit_ceil((static_cast<uint64_t>(size) * 4 + 2) / 3)));
    }

    static void insert_inner(
@ -115,7 +117,7 @@ protected:
                *size += 1;
            }

-            values[result.first_available_index].construct_unsafe(ASL_MOVE(value));
+            values[result.first_available_index].construct_unsafe(std::move(value));
            tags[result.first_available_index] = result.tag;
        }

@ -131,8 +133,8 @@ protected:
    {
        ASL_ASSERT(new_capacity >= kMinCapacity && is_pow2(new_capacity) && new_capacity > m_capacity);

-        auto* new_tags = reinterpret_cast<uint8_t*>(m_allocator.alloc(layout::array<uint8_t>(new_capacity)));
-        auto* new_values = reinterpret_cast<maybe_uninit<T>*>(m_allocator.alloc(layout::array<maybe_uninit<T>>(new_capacity)));
+        auto* new_tags = static_cast<uint8_t*>(m_allocator.alloc(layout::array<uint8_t>(new_capacity)));
+        auto* new_values = static_cast<maybe_uninit<T>*>(m_allocator.alloc(layout::array<maybe_uninit<T>>(new_capacity)));
        asl::memzero(new_tags, new_capacity);

        isize_t new_size = 0;
@ -144,7 +146,7 @@ protected:
            {
                if ((m_tags[i] & kHasValue) == 0) { continue; }

-                insert_inner(ASL_MOVE(m_values[i].as_init_unsafe()), new_tags, new_values, new_capacity, &new_size);
+                insert_inner(std::move(m_values[i].as_init_unsafe()), new_tags, new_values, new_capacity, &new_size);

                // Destroy now so that destroy() has less things to do
                m_values[i].destroy_unsafe();
@ -228,7 +230,6 @@ protected:
        result.tag = static_cast<uint8_t>(hash & kHashMask) | kHasValue;

        // NOLINTBEGIN(*-pointer-arithmetic)
-
        for (
            isize_t i = starting_index;
            i != starting_index || result.first_available_index < 0;
@ -312,7 +313,7 @@ public:
    {}

    explicit constexpr hash_set(Allocator allocator)
-        : m_allocator{ASL_MOVE(allocator)}
+        : m_allocator{std::move(allocator)}
    {}

    hash_set(const hash_set& other)
@ -339,7 +340,7 @@ public:
        , m_values{exchange(other.m_values, nullptr)}
        , m_capacity{exchange(other.m_capacity, 0)}
        , m_size{exchange(other.m_size, 0)}
-        , m_allocator{ASL_MOVE(other.m_allocator)}
+        , m_allocator{std::move(other.m_allocator)}
    {}

    hash_set& operator=(hash_set&& other)
@ -351,7 +352,7 @@ public:
            m_values = exchange(other.m_values, nullptr);
            m_capacity = exchange(other.m_capacity, 0);
            m_size = exchange(other.m_size, 0);
-            m_allocator = ASL_MOVE(other.m_allocator);
+            m_allocator = std::move(other.m_allocator);
        }
        return *this;
    }
@ -385,7 +386,9 @@ public:
        }
    }

-    constexpr isize_t size() const { return m_size; }
+    [[nodiscard]] constexpr isize_t size() const { return m_size; }
+
+    [[nodiscard]] constexpr bool is_empty() const { return m_size == 0; }

    template<typename... Args>
    void insert(Args&&... args)
@ -393,7 +396,7 @@ public:
    {
        maybe_grow_to_fit_one_more();
        ASL_ASSERT(m_size < max_size());
-        insert_inner(ASL_MOVE(T{ASL_FWD(args)...}), m_tags, m_values, m_capacity, &m_size);
+        insert_inner(T{std::forward<Args>(args)...}, m_tags, m_values, m_capacity, &m_size);
    }

    template<typename U>
--- a/asl/containers/hash_set_tests.cpp
+++ b/asl/containers/hash_set_tests.cpp
@ -10,7 +10,7 @@

 ASL_TEST(empty)
 {
-    asl::hash_set<int> set;
+    const asl::hash_set<int> set;

    ASL_TEST_EXPECT(set.size() == 0);

@ -42,7 +42,7 @@ ASL_TEST(a_bunch_of_ints)
 {
    asl::hash_set<int> set;

-    int count = 3000;
+    const int count = 3000;

    for (int i = 0; i < count; ++i)
    {
@ -98,6 +98,7 @@ struct CustomHasher
    }
 };

+// NOLINTNEXTLINE(*-complexity)
 ASL_TEST(destructor_and_remove)
 {
    static constexpr int kCount = 200;
@ -113,9 +114,9 @@ ASL_TEST(destructor_and_remove)

        ASL_TEST_EXPECT(set.size() == kCount);

-        for (int i = 0; i < kCount; ++i)
+        for (const bool i : destroyed)
        {
-            ASL_TEST_EXPECT(!destroyed[i]); // NOLINT
+            ASL_TEST_EXPECT(!i); // NOLINT
        }

        for (int i = 0; i < kCount; i += 2)
@ -132,9 +133,9 @@ ASL_TEST(destructor_and_remove)
        }
    }

-    for (int i = 0; i < kCount; ++i)
+    for (const bool i : destroyed)
    {
-        ASL_TEST_EXPECT(destroyed[i]); // NOLINT
+        ASL_TEST_EXPECT(i); // NOLINT
    }
 }

@ -147,7 +148,7 @@ ASL_TEST(copy)
        set1.insert(i);
    }

-    asl::hash_set<int> set2 = set1;
+    const asl::hash_set<int> set2 = set1;
    asl::hash_set<int> set3;
    set3 = set1;

@ -170,7 +171,7 @@ ASL_TEST(move)
        set1.insert(i);
    }

-    asl::hash_set<int> set2 = ASL_MOVE(set1);
+    asl::hash_set<int> set2 = std::move(set1);

    ASL_TEST_EXPECT(set2.size() == 100);
    for (int i = 0; i < 100; ++i)
@ -178,7 +179,7 @@ ASL_TEST(move)
        ASL_TEST_EXPECT(set2.contains(i));
    }

-    set1 = ASL_MOVE(set2);
+    set1 = std::move(set2);

    ASL_TEST_EXPECT(set1.size() == 100);
    for (int i = 0; i < 100; ++i)
--- a/asl/containers/intrusive_list.hpp
+++ b/asl/containers/intrusive_list.hpp
@ -19,7 +19,7 @@ struct intrusive_list_node
 };

 template<typename T>
-concept is_intrusive_list_node = convertible_from<intrusive_list_node<T>*, T*>;
+concept is_intrusive_list_node = derived_from<T, intrusive_list_node<T>>;

 template<is_intrusive_list_node T>
 class IntrusiveList
@ -43,11 +43,11 @@ public:
        push_front(head);
    }

-    ASL_DELETE_COPY(IntrusiveList)
-    ASL_DEFAULT_MOVE(IntrusiveList)
+    ASL_DELETE_COPY(IntrusiveList);
+    ASL_DEFAULT_MOVE(IntrusiveList);
    ~IntrusiveList() = default;

-    constexpr bool is_empty() const { return m_head == nullptr; }
+    [[nodiscard]] constexpr bool is_empty() const { return m_head == nullptr; }

    void push_front(T* node)
    {
@ -82,13 +82,13 @@ public:

    constexpr auto front(this auto&& self)
    {
-        using return_type = un_ref_t<copy_cref_t<decltype(self), T>>*;
+        using return_type = copy_const_t<un_ref_t<decltype(self)>, T>*;
        return return_type{ self.m_head };
    }

    constexpr auto back(this auto&& self)
    {
-        using return_type = un_ref_t<copy_cref_t<decltype(self), T>>*;
+        using return_type = copy_const_t<un_ref_t<decltype(self)>, T>*;
        return return_type{ self.m_head != nullptr ? self.m_head->m_prev : nullptr };
    }

@ -151,7 +151,7 @@ public:
            , m_advanced{end}
        {}

-        constexpr bool operator==(const generic_iterator& other) const = default;
+        constexpr bool operator==(this generic_iterator, generic_iterator other) = default;

        constexpr generic_iterator& operator++()
        {
@ -167,9 +167,9 @@ public:
            };
        }

-        constexpr TT& operator*() const { return *m_node; }
+        constexpr TT& operator*(this generic_iterator self) { return *self.m_node; }

-        constexpr TT* operator->() const { return m_node; }
+        constexpr TT* operator->(this generic_iterator self) { return self.m_node; }
    };

    using iterator = generic_iterator<T>;
@ -188,5 +188,5 @@ public:
    }
 };

-}
+}  // namespace asl

--- a/asl/containers/intrusive_list_tests.cpp
+++ b/asl/containers/intrusive_list_tests.cpp
@ -23,6 +23,7 @@ ASL_TEST(empty_list)
    ASL_TEST_EXPECT(list.back() == nullptr);
 }

+// NOLINTNEXTLINE(*-complexity)
 ASL_TEST(push_front)
 {
    IntNode one{1};
@ -75,6 +76,7 @@ ASL_TEST(push_front)
    ASL_TEST_ASSERT(it == end);
 }

+// NOLINTNEXTLINE(*-complexity)
 ASL_TEST(push_back)
 {
    IntNode one{1};
--- a/asl/formatting/format.cpp
+++ b/asl/formatting/format.cpp
@ -151,7 +151,7 @@ asl::string_view asl::format_uint64(uint64_t v, asl::span<char, kMaxUint64Digits

    while (v >= 100)
    {
-        uint64_t x = v % 100;
+        const uint64_t x = v % 100;
        v /= 100;
        write_two(s_pairs.subspan(static_cast<isize_t>(x * 2)).first<2>());
    }
@ -195,7 +195,7 @@ void asl::AslFormat(Formatter& f, int64_t v)
    if (v < 0)
    {
        f.write("-");
-        uint64_t absolute_value = ~(bit_cast<uint64_t>(v) - 1);
+        const uint64_t absolute_value = ~(bit_cast<uint64_t>(v) - 1);
        AslFormat(f, absolute_value);
    }
    else
--- a/asl/formatting/format.hpp
+++ b/asl/formatting/format.hpp
@ -5,6 +5,7 @@
 #pragma once

 #include "asl/base/integers.hpp"
+#include "asl/base/float.hpp"
 #include "asl/base/meta.hpp"
 #include "asl/io/writer.hpp"
 #include "asl/types/span.hpp"
@ -32,7 +33,7 @@ struct type_erased_arg
    template<formattable T>
    static constexpr void erased_fn(Formatter& f, const void* data)
    {
-        AslFormat(f, *reinterpret_cast<const T*>(data));
+        AslFormat(f, *static_cast<const T*>(data));
    }

    template<formattable T>
@ -44,7 +45,7 @@ struct type_erased_arg

 void format(Writer*, string_view fmt, span<const type_erased_arg> args);

-} // namespace internals
+}  // namespace format_internals

 class Formatter
 {
@ -60,7 +61,7 @@ public:
        m_writer->write(as_bytes(s.as_span()));
    }

-    constexpr Writer* writer() const { return m_writer; }
+    [[nodiscard]] constexpr Writer* writer() const { return m_writer; }
 };

 template<formattable... Args>
@ -68,7 +69,7 @@ void format(Writer* w, string_view fmt, const Args&... args)
 {
    if constexpr (types_count<Args...> > 0)
    {
-        format_internals::type_erased_arg type_erased_args[] = {
+        const format_internals::type_erased_arg type_erased_args[] = {
            format_internals::type_erased_arg(args)...
        };

@ -93,8 +94,8 @@ inline void AslFormat(Formatter& f, string_view sv)
    f.write(sv);
 }

-void AslFormat(Formatter& f, float);
-void AslFormat(Formatter& f, double);
+void AslFormat(Formatter& f, float32_t);
+void AslFormat(Formatter& f, float64_t);

 void AslFormat(Formatter& f, bool);

--- a/asl/formatting/format_float.cpp
+++ b/asl/formatting/format_float.cpp
@ -4,10 +4,14 @@

 #include "asl/formatting/format.hpp"
 #include "asl/base/float.hpp"
+#include "asl/base/numeric.hpp"

+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Weverything"
 #define JKJ_STD_REPLACEMENT_NAMESPACE_DEFINED 0
 #define JKJ_STATIC_DATA_SECTION_DEFINED 0
 #include <dragonbox.h>
+#pragma clang diagnostic pop

 static constexpr isize_t kZeroCount = 100;
 static constexpr char kZeros[kZeroCount] = {
@ -23,14 +27,14 @@ static constexpr char kZeros[kZeroCount] = {
    '0', '0', '0', '0', '0', '0', '0', '0', '0', '0',
 };

-static constexpr bool is_zero(float x)
+static constexpr bool is_zero(float32_t x)
 {
-    return (asl::bit_cast<uint32_t>(x) & 0x7fff'ffff) == 0;
+    return (asl::bit_cast<uint32_t>(x) & 0x7fff'ffffU) == 0;
 }

-static constexpr bool is_zero(double x)
+static constexpr bool is_zero(float64_t x)
 {
-    return (asl::bit_cast<uint64_t>(x) & 0x7fff'ffff'ffff'ffff) == 0;
+    return (asl::bit_cast<uint64_t>(x) & 0x7fff'ffff'ffff'ffffULL) == 0;
 }

 template<asl::is_floating_point T>
@ -66,15 +70,15 @@ static void format_float(asl::Formatter& f, T value)
    if (decimal.is_negative) { f.write("-"); }

    char buffer[20];
-    asl::string_view digits = asl::format_uint64(decimal.significand, buffer);
+    const asl::string_view digits = asl::format_uint64(decimal.significand, buffer);

    if (decimal.exponent >= 0)
    {
        f.write(digits);
        while (decimal.exponent > 0)
        {
-            isize_t to_write = asl::min(static_cast<isize_t>(decimal.exponent), kZeroCount);
-            f.write(asl::string_view(kZeros, to_write));
+            const isize_t to_write = asl::min(static_cast<isize_t>(decimal.exponent), kZeroCount);
+            f.write(asl::string_view(static_cast<const char*>(kZeros), to_write));
            decimal.exponent -= to_write;
        }
    }
@ -86,8 +90,8 @@ static void format_float(asl::Formatter& f, T value)
            decimal.exponent = -decimal.exponent - static_cast<int>(digits.size());
            while (decimal.exponent > 0)
            {
-                isize_t to_write = asl::min(static_cast<isize_t>(decimal.exponent), kZeroCount);
-                f.write(asl::string_view(kZeros, to_write));
+                const isize_t to_write = asl::min(static_cast<isize_t>(decimal.exponent), kZeroCount);
+                f.write(asl::string_view(static_cast<const char*>(kZeros), to_write));
                decimal.exponent -= to_write;
            }
            f.write(digits);
@ -101,12 +105,12 @@ static void format_float(asl::Formatter& f, T value)
    }
 }

-void asl::AslFormat(Formatter& f, float value)
+void asl::AslFormat(Formatter& f, float32_t value)
 {
    format_float(f, value);
 }

-void asl::AslFormat(Formatter& f, double value)
+void asl::AslFormat(Formatter& f, float64_t value)
 {
    format_float(f, value);
 }
--- a/asl/formatting/format_tests.cpp
+++ b/asl/formatting/format_tests.cpp
@ -79,7 +79,7 @@ ASL_TEST(format_floats)
    s = asl::format_to_string("{}", 123e-8);
    ASL_TEST_EXPECT(s == "0.00000123"_sv);

-    s = asl::format_to_string("{} {}", asl::infinity<float>(), -asl::infinity<double>());
+    s = asl::format_to_string("{} {}", asl::infinity<float32_t>(), -asl::infinity<float64_t>());
    ASL_TEST_EXPECT(s == "Infinity -Infinity"_sv);

    s = asl::format_to_string("{}", asl::nan<float>());
--- a/asl/handle_pool/BUILD.bazel
+++ b/asl/handle_pool/BUILD.bazel
@ -0,0 +1,81 @@
+# Copyright 2025 Steven Le Rouzic
+#
+# SPDX-License-Identifier: BSD-3-Clause
+
+package(
+    default_applicable_licenses = ["//:license"],
+)
+
+cc_library(
+    name = "index_pool",
+    hdrs = [
+        "index_pool.hpp",
+    ],
+    deps = [
+        "//asl/memory",
+        "//asl/memory:allocator",
+        "//asl/base",
+        "//asl/containers:chunked_buffer",
+        "//asl/types:option",
+    ],
+    visibility = ["//visibility:public"],
+)
+
+cc_library(
+    name = "dense_handle_pool",
+    hdrs = [
+        "dense_handle_pool.hpp",
+    ],
+    deps = [
+        ":index_pool",
+    ],
+    visibility = ["//visibility:public"],
+)
+
+cc_library(
+    name = "sparse_handle_pool",
+    hdrs = [
+        "sparse_handle_pool.hpp",
+    ],
+    deps = [
+        ":index_pool",
+    ],
+    visibility = ["//visibility:public"],
+)
+
+cc_test(
+    name = "index_pool_tests",
+    srcs = [
+        "index_pool_tests.cpp",
+    ],
+    deps = [
+        ":index_pool",
+        "//asl/hashing",
+        "//asl/tests:utils",
+        "//asl/testing",
+    ],
+)
+
+cc_test(
+    name = "dense_handle_pool_tests",
+    srcs = [
+        "dense_handle_pool_tests.cpp",
+    ],
+    deps = [
+        ":dense_handle_pool",
+        "//asl/tests:utils",
+        "//asl/testing",
+    ],
+)
+
+cc_test(
+    name = "sparse_handle_pool_tests",
+    srcs = [
+        "sparse_handle_pool_tests.cpp",
+    ],
+    deps = [
+        ":sparse_handle_pool",
+        "//asl/tests:utils",
+        "//asl/testing",
+    ],
+)
--- a/asl/handle_pool/dense_handle_pool.hpp
+++ b/asl/handle_pool/dense_handle_pool.hpp
@ -0,0 +1,162 @@
+// Copyright 2025 Steven Le Rouzic
+//
+// SPDX-License-Identifier: BSD-3-Clause
+
+#pragma once
+
+#include "asl/handle_pool/index_pool.hpp"
+#include "asl/memory/allocator.hpp"
+#include "asl/containers/chunked_buffer.hpp"
+
+
+namespace asl
+{
+
+// @Todo If we want the allocator to be non-copyable, we could
+// introduce a reference allocator type that is copyable, and store
+// the "main" allocator in the pool.
+
+template<
+    is_object T,
+    int kIndexBits,
+    int kGenBits,
+    typename UserType = empty,
+    int kUserBits = 0,
+    isize_t kChunkSize = 32,
+    allocator Allocator = DefaultAllocator>
+requires moveable<T> && copyable<Allocator>
+class DenseHandlePool
+{
+    using ThisIndexPool = IndexPool<kIndexBits, kGenBits, UserType, kUserBits, isize_t, Allocator>;
+
+    struct Slot
+    {
+        ThisIndexPool::handle h;
+        T obj;
+
+        template<typename... Args>
+        explicit Slot(ThisIndexPool::handle h_, Args&&... args)
+            : h{h_}
+            , obj(std::forward<Args>(args)...)
+        {}
+    };
+
+    using Buffer = chunked_buffer<Slot, kChunkSize, Allocator>;
+
+    ThisIndexPool m_index_pool{};
+    Buffer        m_buffer{};
+
+    using config = ThisIndexPool::handle::config;
+
+    template<typename... Args>
+    isize_t push(Args&&... args)
+        requires constructible_from<T, Args&&...>
+    {
+        m_buffer.push(typename ThisIndexPool::handle{}, std::forward<Args>(args)...);
+        return m_buffer.size() - 1;
+    }
+
+public:
+    using handle = ThisIndexPool::handle;
+
+    DenseHandlePool() requires default_constructible<Allocator> = default;
+
+    explicit DenseHandlePool(const Allocator& allocator)
+        : m_index_pool(allocator)
+        , m_buffer(allocator)
+    {}
+
+    ASL_DELETE_COPY(DenseHandlePool);
+    ASL_DEFAULT_MOVE(DenseHandlePool);
+    ~DenseHandlePool() = default;
+
+    [[nodiscard]] bool is_full() const
+    {
+        return m_index_pool.is_full();
+    }
+
+    bool is_valid(handle h) const
+    {
+        return m_index_pool.is_valid(h);
+    }
+
+    template<typename... Args>
+    option<handle> acquire(config::UserType user, Args&&... args)
+        requires config::kHasUser && constructible_from<T, Args&&...>
+    {
+        if (is_full()) { return nullopt; }
+        const isize_t obj_index = push(std::forward<Args>(args)...);
+        const auto handle = m_index_pool.acquire_ensure(user, obj_index);
+        m_buffer[obj_index].h = handle;
+        return handle;
+    }
+
+    template<typename... Args>
+    option<handle> acquire(Args&&... args)
+        requires (!config::kHasUser) && constructible_from<T, Args&&...>
+    {
+        if (is_full()) { return nullopt; }
+        const isize_t obj_index = push(std::forward<Args>(args)...);
+        const auto handle = m_index_pool.acquire_ensure(obj_index);
+        m_buffer[obj_index].h = handle;
+        return handle;
+    }
+
+    template<typename... Args>
+    handle acquire_ensure(config::UserType user, Args&&... args)
+        requires config::kHasUser && constructible_from<T, Args&&...>
+    {
+        ASL_ASSERT_RELEASE(!is_full());
+        const isize_t obj_index = push(std::forward<Args>(args)...);
+        const auto handle = m_index_pool.acquire_ensure(user, obj_index);
+        m_buffer[obj_index].h = handle;
+        return handle;
+    }
+
+    template<typename... Args>
+    handle acquire_ensure(Args&&... args)
+        requires (!config::kHasUser) && constructible_from<T, Args&&...>
+    {
+        ASL_ASSERT_RELEASE(!is_full());
+        const isize_t obj_index = push(std::forward<Args>(args)...);
+        const auto handle = m_index_pool.acquire_ensure(obj_index);
+        m_buffer[obj_index].h = handle;
+        return handle;
+    }
+
+    void release(handle to_release_handle)
+    {
+        if (!is_valid(to_release_handle)) { return; }
+
+        const auto to_release_index = *m_index_pool.get_payload(to_release_handle);
+        if (to_release_index < m_buffer.size() - 1)
+        {
+            const auto to_swap_index = m_buffer.size() - 1;
+            const auto to_swap_handle = m_buffer[to_swap_index].h;
+
+            m_buffer[to_release_index] = std::move(m_buffer[to_swap_index]);
+            m_index_pool.exchange_payload(to_swap_handle, to_release_index);
+        }
+
+        m_buffer.pop();
+        m_index_pool.release(to_release_handle);
+    }
+
+    auto get(this auto&& self, handle h)
+        -> copy_const_t<un_ref_t<decltype(self)>, T>*
+    {
+        if (!self.is_valid(h)) { return nullptr; }
+        const auto index = *self.m_index_pool.get_payload(h);
+        return &self.m_buffer[index].obj;
+    }
+
+    auto get_ensure(this auto&& self, handle h)
+        -> copy_cref_t<decltype(self), T>
+    {
+        ASL_ASSERT_RELEASE(self.is_valid(h));
+        const auto index = *self.m_index_pool.get_payload(h);
+        return std::forward<decltype(self)>(self).m_buffer[index].obj;
+    }
+};
+
+} // namespace asl
--- a/asl/handle_pool/dense_handle_pool_tests.cpp
+++ b/asl/handle_pool/dense_handle_pool_tests.cpp
@ -0,0 +1,117 @@
+// Copyright 2025 Steven Le Rouzic
+//
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include "asl/testing/testing.hpp"
+#include "asl/tests/types.hpp"
+#include "asl/handle_pool/dense_handle_pool.hpp"
+
+ASL_TEST(acquire_release) // NOLINT
+{
+    asl::DenseHandlePool<int, 1, 1> pool;
+
+    ASL_TEST_EXPECT(!pool.is_full());
+
+    const auto a = pool.acquire_ensure(6);
+    const auto b = pool.acquire_ensure(7);
+
+    ASL_TEST_EXPECT(pool.is_valid(a));
+    ASL_TEST_EXPECT(pool.is_valid(b));
+    ASL_TEST_EXPECT(pool.is_full());
+
+    ASL_TEST_EXPECT(pool.get_ensure(a) == 6);
+    ASL_TEST_EXPECT(pool.get_ensure(b) == 7);
+
+    pool.release(a);
+    ASL_TEST_EXPECT(!pool.is_valid(a));
+    ASL_TEST_EXPECT(pool.is_valid(b));
+    ASL_TEST_EXPECT(!pool.is_full());
+    ASL_TEST_EXPECT(pool.get(a) == nullptr);
+    ASL_TEST_EXPECT(*pool.get(b) == 7);
+
+    const auto c = pool.acquire_ensure(8);
+
+    ASL_TEST_EXPECT(!pool.is_valid(a));
+    ASL_TEST_EXPECT(pool.is_valid(b));
+    ASL_TEST_EXPECT(pool.is_valid(c));
+    ASL_TEST_EXPECT(pool.is_full());
+
+    ASL_TEST_EXPECT(*pool.get(b) == 7);
+    ASL_TEST_EXPECT(*pool.get(c) == 8);
+    ASL_TEST_EXPECT(pool.get(a) == nullptr);
+}
+
+ASL_TEST(element_destructor)
+{
+    asl::DenseHandlePool<DestructorObserver, 8, 8> pool;
+    bool d[3]{};
+
+    const auto d0 = pool.acquire_ensure(&d[0]);
+    const auto d1 = pool.acquire_ensure(&d[1]);
+    const auto d2 = pool.acquire_ensure(&d[2]);
+
+    ASL_TEST_EXPECT(!d[0]);
+    ASL_TEST_EXPECT(!d[1]);
+    ASL_TEST_EXPECT(!d[2]);
+
+    pool.release(d1);
+    ASL_TEST_EXPECT(!d[0]);
+    ASL_TEST_EXPECT(d[1]);
+    ASL_TEST_EXPECT(!d[2]);
+
+    pool.release(d0);
+    ASL_TEST_EXPECT(d[0]);
+    ASL_TEST_EXPECT(d[1]);
+    ASL_TEST_EXPECT(!d[2]);
+
+    pool.release(d2);
+    ASL_TEST_EXPECT(d[0]);
+    ASL_TEST_EXPECT(d[1]);
+    ASL_TEST_EXPECT(d[2]);
+}
+
+ASL_TEST(destructor)
+{
+    bool d[3]{};
+
+    {
+        asl::DenseHandlePool<DestructorObserver, 8, 8> pool;
+
+        pool.acquire_ensure(&d[0]);
+        const auto d1 = pool.acquire_ensure(&d[1]);
+        pool.acquire_ensure(&d[2]);
+
+        ASL_TEST_EXPECT(!d[0]);
+        ASL_TEST_EXPECT(!d[1]);
+        ASL_TEST_EXPECT(!d[2]);
+
+        pool.release(d1);
+        ASL_TEST_EXPECT(!d[0]);
+        ASL_TEST_EXPECT(d[1]);
+        ASL_TEST_EXPECT(!d[2]);
+    }
+
+    ASL_TEST_EXPECT(d[0]);
+    ASL_TEST_EXPECT(d[1]);
+    ASL_TEST_EXPECT(d[2]);
+}
+
+enum Flags : uint8_t
+{
+    kFlag1 = 1,
+    kFlag2 = 2,
+};
+
+ASL_TEST(user_type)
+{
+    asl::DenseHandlePool<int, 8, 8, Flags> pool;
+
+    auto a = pool.acquire_ensure(kFlag2, 22);
+    auto b = pool.acquire_ensure(kFlag1, 11);
+
+    ASL_TEST_EXPECT(pool.get_ensure(a) == 22);
+    ASL_TEST_EXPECT(pool.get_ensure(b) == 11);
+
+    ASL_TEST_EXPECT(a.user() == kFlag2);
+    ASL_TEST_EXPECT(b.user() == kFlag1);
+}
--- a/asl/handle_pool/index_pool.hpp
+++ b/asl/handle_pool/index_pool.hpp
@ -0,0 +1,378 @@
+// Copyright 2025 Steven Le Rouzic
+//
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include "asl/base/integers.hpp"
+#include "asl/base/meta.hpp"
+#include "asl/containers/chunked_buffer.hpp"
+#include "asl/memory/allocator.hpp"
+#include "asl/types/option.hpp"
+
+namespace asl
+{
+
+template<
+    int kIndexBits_,
+    int kGenBits_,
+    typename UserType_ = empty,
+    int kUserBits_ = 0
+>
+requires (kIndexBits_ > 0 && kGenBits_ > 0 && kUserBits_ >= 0)
+struct index_pool_config
+{
+    static constexpr bool kHasUser = !same_as<UserType_, empty>;
+
+    using UserType          = UserType_;
+    using PrimitiveUserType = smallest_unsigned_integer_type_for_width<size_of<UserType> * 8>;
+
+    static_assert(trivially_copy_constructible<UserType>);
+    static_assert(trivially_destructible<UserType>);
+    static_assert(size_of<UserType> == size_of<PrimitiveUserType>, "UserType should be of size 1, 2 or 4");
+
+    static constexpr int kUserBits = []() static -> int {
+        if constexpr (!kHasUser) { return 0; };
+        return kUserBits_ == 0 ? size_of<UserType> * 8 : kUserBits_;
+    }();
+
+    static_assert(kUserBits <= size_of<UserType> * 8);
+
+    static constexpr int kIndexBits = kIndexBits_;
+    static constexpr int kGenBits   = kGenBits_;
+
+    static_assert(kIndexBits + kGenBits + kUserBits <= 63);
+
+    using HandleType = smallest_unsigned_integer_type_for_width<kIndexBits + kGenBits + kUserBits + 1>;
+
+    static constexpr int        kGenShift  = kIndexBits;
+    static constexpr int        kUserShift = kIndexBits + kGenBits;
+
+    static constexpr HandleType kValidMask = HandleType{1} << (size_of<HandleType> * 8 - 1);
+    static constexpr HandleType kIndexMask = (HandleType{1} << kIndexBits) - 1;
+    static constexpr HandleType kGenMask   = ((HandleType{1} << kGenBits) - 1) << kGenShift;
+    static constexpr HandleType kUserMask  = ((HandleType{1} << kUserBits) - 1) << kUserShift;
+    static constexpr HandleType kNiche     = static_cast<HandleType>(~uint64_t{kValidMask});
+
+    static constexpr uint64_t   kMaxGen    = (uint64_t{1} << kGenBits) - 1;
+    static constexpr uint64_t   kMaxIndex  = (uint64_t{1} << kIndexBits) - 1;
+};
+
+template<
+    int kIndexBits_,
+    int kGenBits_,
+    typename UserType_ = empty,
+    int kUserBits_ = 0
+>
+class index_pool_handle
+{
+public:
+    using config = index_pool_config<kIndexBits_, kGenBits_, UserType_, kUserBits_>;
+
+private:
+    config::HandleType m_handle{};
+
+public:
+    constexpr index_pool_handle() = default;
+
+    constexpr explicit index_pool_handle(niche_t)
+        : m_handle{config::kNiche}
+    {}
+
+    constexpr index_pool_handle(uint64_t index, uint64_t gen)
+        requires (!config::kHasUser)
+        : m_handle{static_cast<config::HandleType>(
+            config::kValidMask |
+            (index & config::kIndexMask) |
+            ((gen << config::kGenShift) & config::kGenMask))}
+    {
+        ASL_ASSERT((index & uint64_t{config::kIndexMask}) == index);
+        ASL_ASSERT((gen & (uint64_t{config::kGenMask} >> config::kGenShift)) == gen);
+    }
+
+    constexpr index_pool_handle(uint64_t index, uint64_t gen, config::UserType user)
+        requires config::kHasUser
+        : m_handle{static_cast<config::HandleType>(
+            config::kValidMask |
+            (index & config::kIndexMask) |
+            ((gen << config::kGenShift) & config::kGenMask) |
+            ((static_cast<config::HandleType>(bit_cast<typename config::PrimitiveUserType>(user)) << config::kUserShift) & config::kUserMask))}
+    {
+        ASL_ASSERT((index & uint64_t{config::kIndexMask}) == index);
+        ASL_ASSERT((gen & (uint64_t{config::kGenMask} >> config::kGenShift)) == gen);
+        ASL_ASSERT((bit_cast<typename config::PrimitiveUserType>(user) & (uint64_t{config::kUserMask} >> config::kUserShift)) == bit_cast<typename config::PrimitiveUserType>(user));
+    }
+
+    constexpr bool is_null(this index_pool_handle self)
+    {
+        return !(self.m_handle & config::kValidMask);
+    }
+
+    constexpr uint64_t index(this index_pool_handle self)
+    {
+        return self.m_handle & config::kIndexMask;
+    }
+
+    constexpr uint64_t gen(this index_pool_handle self)
+    {
+        return (self.m_handle & config::kGenMask) >> config::kGenShift;
+    }
+
+    constexpr config::UserType user(this index_pool_handle self)
+    {
+        return bit_cast<typename config::UserType>(static_cast<config::PrimitiveUserType>(
+            ((self.m_handle & config::kUserMask) >> config::kUserShift)));
+    }
+
+    constexpr bool operator==(this index_pool_handle self, index_pool_handle other) = default;
+
+    constexpr bool operator==(this index_pool_handle self, niche_t)
+    {
+        return self.m_handle == config::kNiche;
+    }
+};
+
+template<
+    int kIndexBits_,
+    int kGenBits_,
+    typename UserType_,
+    int kUserBits_
+>
+struct is_uniquely_represented<index_pool_handle<kIndexBits_, kGenBits_, UserType_, kUserBits_>> : true_type {};
+
+template<
+    int kIndexBits_,
+    int kGenBits_,
+    typename UserType_ = empty,
+    int kUserBits_ = 0,
+    typename Payload = empty,
+    allocator Allocator = DefaultAllocator
+>
+class IndexPool
+{
+public:
+    using handle = index_pool_handle<kIndexBits_, kGenBits_, UserType_, kUserBits_>;
+
+private:
+    using config = handle::config;
+
+    using internal_handle = index_pool_handle<
+        kIndexBits_,
+        kGenBits_,
+        typename config::PrimitiveUserType,
+        kUserBits_>;
+
+    static constexpr bool kHasPayload = !same_as<Payload, empty>;
+
+    // @Todo Remove need for default constructible & trivially destructible for payload
+    // Use maybe_uninit for it
+
+    static_assert(default_constructible<Payload>);
+    static_assert(copy_constructible<Payload>);
+    static_assert(trivially_destructible<Payload>);
+
+    struct Slot
+    {
+        bool is_end_of_list : 1;
+        bool is_active      : 1;
+
+        internal_handle handle;
+
+        ASL_NO_UNIQUE_ADDRESS Payload payload;
+    };
+
+    chunked_buffer<Slot, 256, Allocator> m_slots;
+
+    // We only use the index, this is essentially the head of the linked
+    // list to the first available slot.
+    // Then the index of each slot points to the next available one.
+    internal_handle m_first_available;
+
+    void allocate_new_slot()
+    {
+        const auto new_index = static_cast<uint64_t>(m_slots.size());
+        if (new_index > config::kMaxIndex) { return; }
+
+        const internal_handle new_handle = internal_handle(new_index, 0, 0);
+
+        m_slots.push(Slot{
+            .is_end_of_list = true,
+            .is_active      = false,
+            .handle         = new_handle,
+            .payload        = Payload{}
+        });
+
+        m_first_available = new_handle;
+    }
+
+    option<internal_handle> acquire_handle(const Payload& payload)
+    {
+        if (m_first_available.is_null())
+        {
+            allocate_new_slot();
+        }
+
+        if (m_first_available.is_null())
+        {
+            return nullopt;
+        }
+
+        auto index = m_first_available.index();
+
+        Slot& slot = m_slots[static_cast<isize_t>(index)];
+        ASL_ASSERT(!slot.is_active);
+
+        m_first_available = slot.is_end_of_list ? internal_handle{} : slot.handle;
+
+        slot.is_active = true;
+        slot.payload   = payload;
+
+        return internal_handle(index, slot.handle.gen(), 0);
+    }
+
+    auto get_slot_if_valid(this auto&& self, handle h)
+        -> copy_const_t<decltype(self), Slot>*
+    {
+        if (h.is_null()) { return nullptr; }
+
+        auto index = static_cast<isize_t>(h.index());
+        if (index < 0 || index >= self.m_slots.size()) { return nullptr; }
+
+        auto& slot = self.m_slots[index];
+        if (!slot.is_active || slot.handle.gen() != h.gen())
+        {
+            return nullptr;
+        }
+
+        return &slot;
+    }
+
+public:
+    IndexPool() requires default_constructible<Allocator> = default;
+
+    explicit IndexPool(Allocator allocator) : m_slots{std::move(allocator)} {}
+
+    [[nodiscard]] bool is_full() const
+    {
+        return m_first_available.is_null()
+            && static_cast<uint64_t>(m_slots.size()) > config::kMaxIndex;
+    }
+
+    option<handle> acquire()
+        requires (!kHasPayload && !config::kHasUser)
+    {
+        return acquire_handle({}).transform([](internal_handle h)
+        {
+            return handle(h.index(), h.gen());
+        });
+    }
+
+    handle acquire_ensure()
+        requires (!kHasPayload && !config::kHasUser)
+    {
+        auto opt = acquire();
+        ASL_ASSERT_RELEASE(opt.has_value());
+        return opt.value();
+    }
+
+    option<handle> acquire(const Payload& payload)
+        requires (kHasPayload && !config::kHasUser)
+    {
+        return acquire_handle(payload).transform([](internal_handle h)
+        {
+            return handle(h.index(), h.gen());
+        });
+    }
+
+    handle acquire_ensure(const Payload& payload)
+        requires (kHasPayload && !config::kHasUser)
+    {
+        auto opt = acquire(payload);
+        ASL_ASSERT_RELEASE(opt.has_value());
+        return opt.value();
+    }
+
+    option<handle> acquire(config::UserType user)
+        requires (!kHasPayload && config::kHasUser)
+    {
+        return acquire_handle({}).transform([user](internal_handle h)
+        {
+            return handle(h.index(), h.gen(), user);
+        });
+    }
+
+    handle acquire_ensure(config::UserType user)
+        requires (!kHasPayload && config::kHasUser)
+    {
+        auto opt = acquire(user);
+        ASL_ASSERT_RELEASE(opt.has_value());
+        return opt.value();
+    }
+
+    option<handle> acquire(config::UserType user, const Payload& payload)
+        requires (kHasPayload && config::kHasUser)
+    {
+        return acquire_handle(payload).transform([user](internal_handle h)
+        {
+            return handle(h.index(), h.gen(), user);
+        });
+    }
+
+    handle acquire_ensure(config::UserType user, const Payload& payload)
+        requires (kHasPayload && config::kHasUser)
+    {
+        auto opt = acquire(user, payload);
+        ASL_ASSERT_RELEASE(opt.has_value());
+        return opt.value();
+    }
+
+    // @Todo Add a policy to abandon slots that reached max generation
+    void release(handle h)
+    {
+        if (Slot* slot = get_slot_if_valid(h); slot != nullptr)
+        {
+            const uint64_t next_gen = h.gen() == config::kMaxGen ? 0 : h.gen() + 1;
+
+            slot->is_active = false;
+
+            if (m_first_available.is_null())
+            {
+                slot->is_end_of_list = true;
+                slot->handle = internal_handle(h.index(), next_gen, 0);
+            }
+            else
+            {
+                slot->is_end_of_list = false;
+                slot->handle = internal_handle(m_first_available.index(), next_gen, 0);
+            }
+
+            m_first_available = internal_handle(h.index(), 0, 0);
+        }
+    }
+
+    bool is_valid(handle h) const
+    {
+        return get_slot_if_valid(h) != nullptr;
+    }
+
+    const Payload* get_payload(handle h) const
+        requires kHasPayload
+    {
+        if (const Slot* slot = get_slot_if_valid(h); slot != nullptr)
+        {
+            return &slot->payload;
+        }
+        return nullptr;
+    }
+
+    option<Payload> exchange_payload(handle h, Payload new_payload)
+        requires kHasPayload
+    {
+        if (Slot* slot = get_slot_if_valid(h); slot != nullptr)
+        {
+            return asl::exchange(slot->payload, new_payload);
+        }
+        return nullopt;
+    }
+};
+
+} // namespace asl
+
--- a/asl/handle_pool/index_pool_tests.cpp
+++ b/asl/handle_pool/index_pool_tests.cpp
@ -0,0 +1,348 @@
+// Copyright 2025 Steven Le Rouzic
+//
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include "asl/testing/testing.hpp"
+#include "asl/handle_pool/index_pool.hpp"
+#include "asl/hashing/hash.hpp"
+
+enum Flags: uint8_t {
+    kFlag0 = 0,
+    kFlag1 = 1,
+    kFlag2 = 2,
+};
+
+using Cfg1 = asl::index_pool_config<4, 3>;
+static_assert(!Cfg1::kHasUser);
+static_assert(Cfg1::kUserBits == 0);
+static_assert(asl::same_as<Cfg1::HandleType, uint8_t>);
+static_assert(Cfg1::kValidMask == uint8_t{0x80});
+static_assert(Cfg1::kIndexMask == uint8_t{0x0f});
+static_assert(Cfg1::kGenMask   == uint8_t{0x70});
+static_assert(Cfg1::kGenShift  == 4);
+static_assert(Cfg1::kMaxGen    == 7);
+static_assert(Cfg1::kMaxIndex  == 15);
+
+using Cfg2 = asl::index_pool_config<5, 5, Flags>;
+static_assert(Cfg2::kHasUser);
+static_assert(Cfg2::kUserBits == 8);
+static_assert(asl::same_as<Cfg2::PrimitiveUserType, uint8_t>);
+static_assert(asl::same_as<Cfg2::HandleType, uint32_t>);
+static_assert(Cfg2::kValidMask == uint32_t{0x8000'0000});
+static_assert(Cfg2::kIndexMask == uint32_t{0x0000'001f});
+static_assert(Cfg2::kGenMask   == uint32_t{0x0000'03e0});
+static_assert(Cfg2::kUserMask  == uint32_t{0x0003'fc00});
+static_assert(Cfg2::kGenShift  == 5);
+static_assert(Cfg2::kUserShift == 10);
+static_assert(Cfg2::kMaxGen    == 31);
+static_assert(Cfg2::kMaxIndex  == 31);
+
+using Cfg3 = asl::index_pool_config<5, 6, Flags, 4>;
+static_assert(Cfg3::kHasUser);
+static_assert(Cfg3::kUserBits == 4);
+static_assert(asl::same_as<Cfg3::PrimitiveUserType, uint8_t>);
+static_assert(asl::same_as<Cfg3::HandleType, uint16_t>);
+static_assert(Cfg3::kValidMask == uint16_t{0x8000});
+static_assert(Cfg3::kIndexMask == uint16_t{0x001f});
+static_assert(Cfg3::kGenMask   == uint16_t{0x07e0});
+static_assert(Cfg3::kUserMask  == uint16_t{0x7800});
+static_assert(Cfg3::kGenShift  == 5);
+static_assert(Cfg3::kUserShift == 11);
+static_assert(Cfg3::kMaxGen    == 63);
+static_assert(Cfg3::kMaxIndex  == 31);
+
+static_assert(asl::default_constructible<asl::index_pool_handle<5, 5, uint8_t>>);
+static_assert(asl::trivially_copy_constructible<asl::index_pool_handle<5, 5, uint8_t>>);
+static_assert(asl::trivially_move_constructible<asl::index_pool_handle<5, 5, uint8_t>>);
+static_assert(asl::trivially_copy_assignable<asl::index_pool_handle<5, 5, uint8_t>>);
+static_assert(asl::trivially_move_assignable<asl::index_pool_handle<5, 5, uint8_t>>);
+static_assert(asl::trivially_destructible<asl::index_pool_handle<5, 5, uint8_t>>);
+
+static_assert(asl::hashable<asl::index_pool_handle<5, 5, uint8_t>>);
+static_assert(asl::has_niche<asl::index_pool_handle<5, 5, uint8_t>>);
+
+ASL_TEST(default_is_invalid)
+{
+    const asl::index_pool_handle<5, 5, uint8_t> idx;
+    ASL_TEST_EXPECT(idx.is_null());
+}
+
+ASL_TEST(niche_is_invalid)
+{
+    const asl::index_pool_handle<5, 5, uint8_t> idx{asl::niche_t{}};
+    ASL_TEST_EXPECT(idx.is_null());
+}
+
+ASL_TEST(construct)
+{
+    const asl::index_pool_handle<5, 5> idx(9, 11);
+    ASL_TEST_EXPECT(!idx.is_null());
+    ASL_TEST_EXPECT(idx.index() == 9);
+    ASL_TEST_EXPECT(idx.gen() == 11);
+}
+
+ASL_TEST(construct_user)
+{
+    const asl::index_pool_handle<5, 5, Flags, 4> idx(9, 11, kFlag2);
+    ASL_TEST_EXPECT(!idx.is_null());
+    ASL_TEST_EXPECT(idx.index() == 9);
+    ASL_TEST_EXPECT(idx.gen() == 11);
+    ASL_TEST_EXPECT(idx.user() == kFlag2);
+    static_assert(asl::same_as<Flags, decltype(idx.user())>);
+}
+
+ASL_TEST(compare) // NOLINT
+{
+    const asl::index_pool_handle<5, 5, Flags, 4> idx_default;
+    const asl::index_pool_handle<5, 5, Flags, 4> idx0;
+    const asl::index_pool_handle<5, 5, Flags, 4> idx1(9, 11, kFlag2);
+    const asl::index_pool_handle<5, 5, Flags, 4> idx2(9, 11, kFlag1);
+    const asl::index_pool_handle<5, 5, Flags, 4> idx3(9, 11, kFlag1);
+    const asl::index_pool_handle<5, 5, Flags, 4> idx4(9, 10, kFlag2);
+    const asl::index_pool_handle<5, 5, Flags, 4> idx5(8, 11, kFlag2);
+
+    ASL_TEST_EXPECT(idx0 == idx_default);
+
+    ASL_TEST_EXPECT(idx0 != idx1);
+    ASL_TEST_EXPECT(idx0 != idx2);
+    ASL_TEST_EXPECT(idx0 != idx3);
+    ASL_TEST_EXPECT(idx0 != idx4);
+    ASL_TEST_EXPECT(idx0 != idx5);
+
+    ASL_TEST_EXPECT(idx1 != idx2);
+    ASL_TEST_EXPECT(idx1 != idx3);
+    ASL_TEST_EXPECT(idx1 != idx4);
+    ASL_TEST_EXPECT(idx1 != idx5);
+
+    ASL_TEST_EXPECT(idx2 == idx3);
+    ASL_TEST_EXPECT(idx2 != idx4);
+    ASL_TEST_EXPECT(idx2 != idx5);
+
+    ASL_TEST_EXPECT(idx3 != idx4);
+    ASL_TEST_EXPECT(idx3 != idx5);
+
+    ASL_TEST_EXPECT(idx4 != idx5);
+}
+
+ASL_TEST(hashing) // NOLINT
+{
+    const asl::index_pool_handle<4, 4> idx0(asl::niche_t{});
+    const asl::index_pool_handle<4, 4> idx1{};
+    const asl::index_pool_handle<4, 4> idx2(1, 1);
+    const asl::index_pool_handle<4, 4> idx3(1, 1);
+    const asl::index_pool_handle<4, 4> idx4(2, 1);
+    const asl::index_pool_handle<4, 4> idx5(1, 2);
+
+    ASL_TEST_EXPECT(asl::hash_value(idx0) != asl::hash_value(idx1));
+    ASL_TEST_EXPECT(asl::hash_value(idx0) != asl::hash_value(idx2));
+    ASL_TEST_EXPECT(asl::hash_value(idx0) != asl::hash_value(idx3));
+    ASL_TEST_EXPECT(asl::hash_value(idx0) != asl::hash_value(idx4));
+    ASL_TEST_EXPECT(asl::hash_value(idx0) != asl::hash_value(idx5));
+
+    ASL_TEST_EXPECT(asl::hash_value(idx1) != asl::hash_value(idx2));
+    ASL_TEST_EXPECT(asl::hash_value(idx1) != asl::hash_value(idx3));
+    ASL_TEST_EXPECT(asl::hash_value(idx1) != asl::hash_value(idx4));
+    ASL_TEST_EXPECT(asl::hash_value(idx1) != asl::hash_value(idx5));
+
+    ASL_TEST_EXPECT(asl::hash_value(idx2) == asl::hash_value(idx3));
+    ASL_TEST_EXPECT(asl::hash_value(idx2) != asl::hash_value(idx4));
+    ASL_TEST_EXPECT(asl::hash_value(idx2) != asl::hash_value(idx5));
+
+    ASL_TEST_EXPECT(asl::hash_value(idx3) != asl::hash_value(idx4));
+    ASL_TEST_EXPECT(asl::hash_value(idx3) != asl::hash_value(idx5));
+
+    ASL_TEST_EXPECT(asl::hash_value(idx4) != asl::hash_value(idx5));
+}
+
+ASL_TEST(hashing_in_option) // NOLINT
+{
+    const asl::option<asl::index_pool_handle<4, 4>> idx0;
+    const asl::option<asl::index_pool_handle<4, 4>> idx1{asl::index_pool_handle<4, 4>()};
+    const asl::option<asl::index_pool_handle<4, 4>> idx2{asl::index_pool_handle<4, 4>(1, 1)};
+    const asl::option<asl::index_pool_handle<4, 4>> idx3{asl::index_pool_handle<4, 4>(1, 1)};
+    const asl::option<asl::index_pool_handle<4, 4>> idx4{asl::index_pool_handle<4, 4>(2, 1)};
+    const asl::option<asl::index_pool_handle<4, 4>> idx5{asl::index_pool_handle<4, 4>(1, 2)};
+
+    ASL_TEST_EXPECT(asl::hash_value(idx0) != asl::hash_value(idx1));
+    ASL_TEST_EXPECT(asl::hash_value(idx0) != asl::hash_value(idx2));
+    ASL_TEST_EXPECT(asl::hash_value(idx0) != asl::hash_value(idx3));
+    ASL_TEST_EXPECT(asl::hash_value(idx0) != asl::hash_value(idx4));
+    ASL_TEST_EXPECT(asl::hash_value(idx0) != asl::hash_value(idx5));
+
+    ASL_TEST_EXPECT(asl::hash_value(idx1) != asl::hash_value(idx2));
+    ASL_TEST_EXPECT(asl::hash_value(idx1) != asl::hash_value(idx3));
+    ASL_TEST_EXPECT(asl::hash_value(idx1) != asl::hash_value(idx4));
+    ASL_TEST_EXPECT(asl::hash_value(idx1) != asl::hash_value(idx5));
+
+    ASL_TEST_EXPECT(asl::hash_value(idx2) == asl::hash_value(idx3));
+    ASL_TEST_EXPECT(asl::hash_value(idx2) != asl::hash_value(idx4));
+    ASL_TEST_EXPECT(asl::hash_value(idx2) != asl::hash_value(idx5));
+
+    ASL_TEST_EXPECT(asl::hash_value(idx3) != asl::hash_value(idx4));
+    ASL_TEST_EXPECT(asl::hash_value(idx3) != asl::hash_value(idx5));
+
+    ASL_TEST_EXPECT(asl::hash_value(idx4) != asl::hash_value(idx5));
+}
+
+ASL_TEST(simple_pool) // NOLINT
+{
+    using Pool = asl::IndexPool<8, 8>;
+    Pool pool;
+
+    auto a = pool.acquire_ensure();
+    auto b = pool.acquire_ensure();
+
+    ASL_TEST_EXPECT(!a.is_null());
+    ASL_TEST_EXPECT(!b.is_null());
+    ASL_TEST_EXPECT(a.index() == 0);
+    ASL_TEST_EXPECT(b.index() == 1);
+    ASL_TEST_EXPECT(a.gen() == 0);
+    ASL_TEST_EXPECT(b.gen() == 0);
+    ASL_TEST_EXPECT(!pool.is_full());
+
+    ASL_TEST_EXPECT(a != b);
+
+    ASL_TEST_EXPECT(!pool.is_valid({}));
+    ASL_TEST_EXPECT(pool.is_valid(a));
+    ASL_TEST_EXPECT(pool.is_valid(b));
+
+    pool.release(a);
+
+    ASL_TEST_EXPECT(!pool.is_valid(a));
+    ASL_TEST_EXPECT(pool.is_valid(b));
+
+    auto c = pool.acquire_ensure();
+
+    ASL_TEST_EXPECT(!c.is_null());
+    ASL_TEST_EXPECT(c.index() == 0);
+    ASL_TEST_EXPECT(c.gen() == 1);
+
+    ASL_TEST_EXPECT(a != c);
+    ASL_TEST_EXPECT(b != c);
+
+    ASL_TEST_EXPECT(!pool.is_valid(a));
+    ASL_TEST_EXPECT(pool.is_valid(b));
+    ASL_TEST_EXPECT(pool.is_valid(c));
+
+    pool.release(b);
+
+    ASL_TEST_EXPECT(!pool.is_valid(a));
+    ASL_TEST_EXPECT(!pool.is_valid(b));
+    ASL_TEST_EXPECT(pool.is_valid(c));
+
+    pool.release(c);
+
+    ASL_TEST_EXPECT(!pool.is_valid(a));
+    ASL_TEST_EXPECT(!pool.is_valid(b));
+    ASL_TEST_EXPECT(!pool.is_valid(c));
+}
+
+ASL_TEST(pool_acquire_release_a_lot)
+{
+    using Pool = asl::IndexPool<3, 3>;
+    Pool pool;
+
+    for (int i = 0; i < 80; ++i)
+    {
+        pool.release(pool.acquire_ensure());
+        ASL_TEST_EXPECT(!pool.is_full());
+    }
+}
+
+ASL_TEST(pool_acquire_past_capacity)
+{
+    using Pool = asl::IndexPool<3, 3>;
+    Pool pool;
+
+    auto idx = pool.acquire_ensure();
+
+    for (int i = 0; i < 7; ++i)
+    {
+        ASL_TEST_EXPECT(!pool.is_full());
+        ASL_TEST_EXPECT(pool.acquire().has_value());
+    }
+
+    for (int i = 0; i < 8; ++i)
+    {
+        ASL_TEST_EXPECT(pool.is_full());
+        ASL_TEST_EXPECT(!pool.acquire().has_value());
+    }
+
+    pool.release(idx);
+    ASL_TEST_EXPECT(!pool.is_full());
+    ASL_TEST_EXPECT(pool.acquire().has_value());
+    ASL_TEST_EXPECT(pool.is_full());
+    ASL_TEST_EXPECT(!pool.acquire().has_value());
+}
+
+ASL_TEST(pool_with_user_type)
+{
+    using Pool = asl::IndexPool<8, 8, Flags, 4>;
+    Pool pool;
+
+    const auto a = pool.acquire_ensure(kFlag0);
+    const auto b = pool.acquire_ensure(kFlag2);
+
+    ASL_TEST_EXPECT(a.user() == kFlag0);
+    ASL_TEST_EXPECT(b.user() == kFlag2);
+}
+
+ASL_TEST(pool_with_payload)
+{
+    using Pool = asl::IndexPool<8, 8, asl::empty, 0, int>;
+    Pool pool;
+
+    const auto a = pool.acquire_ensure(37);
+    const auto b = pool.acquire_ensure(28);
+
+    ASL_TEST_EXPECT(*pool.get_payload(a) == 37);
+    ASL_TEST_EXPECT(*pool.get_payload(b) == 28);
+    ASL_TEST_EXPECT(pool.get_payload({}) == nullptr);
+
+    pool.release(a);
+
+    ASL_TEST_EXPECT(pool.get_payload(a) == nullptr);
+    ASL_TEST_EXPECT(*pool.get_payload(b) == 28);
+}
+
+ASL_TEST(pool_with_payload_and_user)
+{
+    using Pool = asl::IndexPool<8, 8, Flags, 8, int>;
+    Pool pool;
+
+    const auto a = pool.acquire_ensure(kFlag1, 37);
+    const auto b = pool.acquire_ensure(kFlag0, 28);
+
+    ASL_TEST_EXPECT(a.user() == kFlag1);
+    ASL_TEST_EXPECT(b.user() == kFlag0);
+
+    ASL_TEST_EXPECT(*pool.get_payload(a) == 37);
+    ASL_TEST_EXPECT(*pool.get_payload(b) == 28);
+    ASL_TEST_EXPECT(pool.get_payload({}) == nullptr);
+
+    pool.release(a);
+
+    ASL_TEST_EXPECT(pool.get_payload(a) == nullptr);
+    ASL_TEST_EXPECT(*pool.get_payload(b) == 28);
+}
+
+ASL_TEST(pool_exchange_payload)
+{
+    using Pool = asl::IndexPool<8, 8, asl::empty, 0, int>;
+    Pool pool;
+
+    const auto a = pool.acquire_ensure(37);
+    const auto b = pool.acquire_ensure(28);
+
+    ASL_TEST_EXPECT(*pool.get_payload(a) == 37);
+    ASL_TEST_EXPECT(*pool.get_payload(b) == 28);
+
+    ASL_TEST_EXPECT(!pool.exchange_payload({}, 0).has_value());
+
+    ASL_TEST_EXPECT(pool.exchange_payload(a, 101).value() == 37);
+    ASL_TEST_EXPECT(pool.exchange_payload(b, 102).value() == 28);
+
+    ASL_TEST_EXPECT(*pool.get_payload(a) == 101);
+    ASL_TEST_EXPECT(*pool.get_payload(b) == 102);
+}
+
--- a/asl/handle_pool/sparse_handle_pool.hpp
+++ b/asl/handle_pool/sparse_handle_pool.hpp
@ -0,0 +1,158 @@
+// Copyright 2025 Steven Le Rouzic
+//
+// SPDX-License-Identifier: BSD-3-Clause
+
+#pragma once
+
+#include "asl/handle_pool/index_pool.hpp"
+#include "asl/memory/allocator.hpp"
+#include "asl/containers/chunked_buffer.hpp"
+
+
+namespace asl
+{
+
+// @Todo If we want the allocator to be non-copyable, we could
+// introduce a reference allocator type that is copyable, and store
+// the "main" allocator in the pool.
+
+template<
+    is_object T,
+    int kIndexBits,
+    int kGenBits,
+    typename UserType = empty,
+    int kUserBits = 0,
+    isize_t kChunkSize = 32,
+    allocator Allocator = DefaultAllocator>
+requires copyable<Allocator>
+class SparseHandlePool
+{
+    using ThisIndexPool = IndexPool<kIndexBits, kGenBits, UserType, kUserBits, empty, Allocator>;
+
+    struct Slot
+    {
+        ThisIndexPool::handle h;
+        maybe_uninit<T> obj;
+
+        Slot() = default;
+        ASL_DELETE_COPY_MOVE(Slot);
+
+        ~Slot()
+        {
+            if (!h.is_null())
+            {
+                obj.destroy_unsafe();
+            }
+        }
+    };
+
+    using Buffer = chunked_buffer<Slot, kChunkSize, Allocator>;
+
+    ThisIndexPool m_index_pool{};
+    Buffer        m_buffer{};
+
+    using config = ThisIndexPool::handle::config;
+
+    template<typename... Args>
+    void set_object(ThisIndexPool::handle h, Args&&... args)
+    {
+        const auto index = static_cast<isize_t>(h.index());
+        if (m_buffer.size() <= index)
+        {
+            m_buffer.resize(index + 1);
+        }
+        m_buffer[index].h = h;
+        m_buffer[index].obj.construct_unsafe(std::forward<Args>(args)...);
+    }
+
+public:
+    using handle = ThisIndexPool::handle;
+
+    SparseHandlePool() requires default_constructible<Allocator> = default;
+
+    explicit SparseHandlePool(const Allocator& allocator)
+        : m_index_pool(allocator)
+        , m_buffer(allocator)
+    {}
+
+    ASL_DELETE_COPY(SparseHandlePool);
+    ASL_DEFAULT_MOVE(SparseHandlePool);
+    ~SparseHandlePool() = default;
+
+    [[nodiscard]] bool is_full() const
+    {
+        return m_index_pool.is_full();
+    }
+
+    bool is_valid(handle h) const
+    {
+        return m_index_pool.is_valid(h);
+    }
+
+    template<typename... Args>
+    option<handle> acquire(config::UserType user, Args&&... args)
+        requires config::kHasUser && constructible_from<T, Args&&...>
+    {
+        if (is_full()) { return nullopt; }
+        const auto handle = m_index_pool.acquire_ensure(user);
+        set_object(handle, std::forward<Args>(args)...);
+        return handle;
+    }
+
+    template<typename... Args>
+    option<handle> acquire(Args&&... args)
+        requires (!config::kHasUser) && constructible_from<T, Args&&...>
+    {
+        if (is_full()) { return nullopt; }
+        const auto handle = m_index_pool.acquire_ensure();
+        set_object(handle, std::forward<Args>(args)...);
+        return handle;
+    }
+
+    template<typename... Args>
+    handle acquire_ensure(config::UserType user, Args&&... args)
+        requires config::kHasUser && constructible_from<T, Args&&...>
+    {
+        ASL_ASSERT_RELEASE(!is_full());
+        const auto handle = m_index_pool.acquire_ensure(user);
+        set_object(handle, std::forward<Args>(args)...);
+        return handle;
+    }
+
+    template<typename... Args>
+    handle acquire_ensure(Args&&... args)
+        requires (!config::kHasUser) && constructible_from<T, Args&&...>
+    {
+        ASL_ASSERT_RELEASE(!is_full());
+        const auto handle = m_index_pool.acquire_ensure();
+        set_object(handle, std::forward<Args>(args)...);
+        return handle;
+    }
+
+    void release(handle h)
+    {
+        if (!is_valid(h)) { return; }
+        auto& slot = m_buffer[static_cast<isize_t>(h.index())];
+        slot.h = {};
+        slot.obj.destroy_unsafe();
+        m_index_pool.release(h);
+    }
+
+    auto get(this auto&& self, handle h)
+        -> copy_const_t<un_ref_t<decltype(self)>, T>*
+    {
+        if (!self.is_valid(h)) { return nullptr; }
+        return &std::forward<decltype(self)>(self).m_buffer[static_cast<isize_t>(h.index())]
+            .obj.as_init_unsafe();
+    }
+
+    auto get_ensure(this auto&& self, handle h)
+        -> copy_cref_t<decltype(self), T>
+    {
+        ASL_ASSERT_RELEASE(self.is_valid(h));
+        return std::forward<decltype(self)>(self).m_buffer[static_cast<isize_t>(h.index())]
+            .obj.as_init_unsafe();
+    }
+};
+
+} // namespace asl
--- a/asl/handle_pool/sparse_handle_pool_tests.cpp
+++ b/asl/handle_pool/sparse_handle_pool_tests.cpp
@ -0,0 +1,117 @@
+// Copyright 2025 Steven Le Rouzic
+//
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include "asl/testing/testing.hpp"
+#include "asl/tests/types.hpp"
+#include "asl/handle_pool/sparse_handle_pool.hpp"
+
+ASL_TEST(acquire_release) // NOLINT
+{
+    asl::SparseHandlePool<int, 1, 1> pool;
+
+    ASL_TEST_EXPECT(!pool.is_full());
+
+    const auto a = pool.acquire_ensure(6);
+    const auto b = pool.acquire_ensure(7);
+
+    ASL_TEST_EXPECT(pool.is_valid(a));
+    ASL_TEST_EXPECT(pool.is_valid(b));
+    ASL_TEST_EXPECT(pool.is_full());
+
+    ASL_TEST_EXPECT(pool.get_ensure(a) == 6);
+    ASL_TEST_EXPECT(pool.get_ensure(b) == 7);
+
+    pool.release(a);
+    ASL_TEST_EXPECT(!pool.is_valid(a));
+    ASL_TEST_EXPECT(pool.is_valid(b));
+    ASL_TEST_EXPECT(!pool.is_full());
+    ASL_TEST_EXPECT(pool.get(a) == nullptr);
+    ASL_TEST_EXPECT(*pool.get(b) == 7);
+
+    const auto c = pool.acquire_ensure(8);
+
+    ASL_TEST_EXPECT(!pool.is_valid(a));
+    ASL_TEST_EXPECT(pool.is_valid(b));
+    ASL_TEST_EXPECT(pool.is_valid(c));
+    ASL_TEST_EXPECT(pool.is_full());
+
+    ASL_TEST_EXPECT(*pool.get(b) == 7);
+    ASL_TEST_EXPECT(*pool.get(c) == 8);
+    ASL_TEST_EXPECT(pool.get(a) == nullptr);
+}
+
+ASL_TEST(element_destructor)
+{
+    asl::SparseHandlePool<DestructorObserver, 8, 8> pool;
+    bool d[3]{};
+
+    const auto d0 = pool.acquire_ensure(&d[0]);
+    const auto d1 = pool.acquire_ensure(&d[1]);
+    const auto d2 = pool.acquire_ensure(&d[2]);
+
+    ASL_TEST_EXPECT(!d[0]);
+    ASL_TEST_EXPECT(!d[1]);
+    ASL_TEST_EXPECT(!d[2]);
+
+    pool.release(d1);
+    ASL_TEST_EXPECT(!d[0]);
+    ASL_TEST_EXPECT(d[1]);
+    ASL_TEST_EXPECT(!d[2]);
+
+    pool.release(d0);
+    ASL_TEST_EXPECT(d[0]);
+    ASL_TEST_EXPECT(d[1]);
+    ASL_TEST_EXPECT(!d[2]);
+
+    pool.release(d2);
+    ASL_TEST_EXPECT(d[0]);
+    ASL_TEST_EXPECT(d[1]);
+    ASL_TEST_EXPECT(d[2]);
+}
+
+ASL_TEST(destructor)
+{
+    bool d[3]{};
+
+    {
+        asl::SparseHandlePool<DestructorObserver, 8, 8> pool;
+
+        pool.acquire_ensure(&d[0]);
+        const auto d1 = pool.acquire_ensure(&d[1]);
+        pool.acquire_ensure(&d[2]);
+
+        ASL_TEST_EXPECT(!d[0]);
+        ASL_TEST_EXPECT(!d[1]);
+        ASL_TEST_EXPECT(!d[2]);
+
+        pool.release(d1);
+        ASL_TEST_EXPECT(!d[0]);
+        ASL_TEST_EXPECT(d[1]);
+        ASL_TEST_EXPECT(!d[2]);
+    }
+
+    ASL_TEST_EXPECT(d[0]);
+    ASL_TEST_EXPECT(d[1]);
+    ASL_TEST_EXPECT(d[2]);
+}
+
+enum Flags : uint8_t
+{
+    kFlag1 = 1,
+    kFlag2 = 2,
+};
+
+ASL_TEST(user_type)
+{
+    asl::SparseHandlePool<int, 8, 8, Flags> pool;
+
+    auto a = pool.acquire_ensure(kFlag2, 22);
+    auto b = pool.acquire_ensure(kFlag1, 11);
+
+    ASL_TEST_EXPECT(pool.get_ensure(a) == 22);
+    ASL_TEST_EXPECT(pool.get_ensure(b) == 11);
+
+    ASL_TEST_EXPECT(a.user() == kFlag2);
+    ASL_TEST_EXPECT(b.user() == kFlag1);
+}
--- a/asl/hashing/hash.hpp
+++ b/asl/hashing/hash.hpp
@ -80,7 +80,7 @@ struct HashState
        {
            auto bytes = as_bytes(s);
            auto hashed = city_hash::CityHash128WithSeed(
-                reinterpret_cast<const char*>(bytes.data()),
+                reinterpret_cast<const char*>(bytes.data()), // NOLINT(*-reinterpret-cast)
                static_cast<size_t>(bytes.size()),
                h.state);
            return HashState{hashed};
@ -89,7 +89,7 @@ struct HashState
        {
            for (const auto& value: s)
            {
-                h = AslHashValue(ASL_MOVE(h), value);
+                h = AslHashValue(std::move(h), value);
            }
            return h;
        }
@ -103,7 +103,7 @@ struct HashState
    template<hashable_generic<HashState> Arg, hashable_generic<HashState>... Remaining>
    static constexpr HashState combine(HashState h, const Arg& arg, const Remaining&... remaining)
    {
-        return combine(AslHashValue(ASL_MOVE(h), arg), remaining...);
+        return combine(AslHashValue(std::move(h), arg), remaining...);
    }
 };

@ -113,13 +113,13 @@ concept hashable = hashable_generic<T, HashState>;
 template<typename H, uniquely_represented T>
 constexpr H AslHashValue(H h, const T& value)
 {
-    return H::combine_contiguous(ASL_MOVE(h), span<const T>{&value, 1});
+    return H::combine_contiguous(std::move(h), span<const T>{&value, 1});
 }

 template<typename H>
 constexpr H AslHashValue(H h, bool value)
 {
-    return AslHashValue(ASL_MOVE(h), value ? 1 : 0);
+    return AslHashValue(std::move(h), value ? 1 : 0);
 }

 template<typename H, typename T>
@ -128,7 +128,7 @@ constexpr void AslHashValue(H h, T*); // Don't hash pointers
 template<typename H, hashable T>
 constexpr H AslHashValue(H h, const span<T>& s)
 {
-    return H::combine_contiguous(ASL_MOVE(h), span<const T>{s.data(), s.size()});
+    return H::combine_contiguous(std::move(h), span<const T>{s.data(), s.size()});
 }

 template<hashable T>
--- a/asl/hashing/hash_tests.cpp
+++ b/asl/hashing/hash_tests.cpp
@ -29,10 +29,10 @@ static_assert(asl::hashable<int64_t>);

 ASL_TEST(integers)
 {
-    uint64_t a = asl::hash_value<uint16_t>(45);
-    uint64_t b = asl::hash_value<uint16_t>(45);
-    uint64_t c = asl::hash_value<uint16_t>(46);
-    uint64_t d = asl::hash_value<uint32_t>(45);
+    const uint64_t a = asl::hash_value<uint16_t>(45);
+    const uint64_t b = asl::hash_value<uint16_t>(45);
+    const uint64_t c = asl::hash_value<uint16_t>(46);
+    const uint64_t d = asl::hash_value<uint32_t>(45);

    ASL_TEST_EXPECT(a == b);
    ASL_TEST_EXPECT(a != c);
@ -187,19 +187,19 @@ static_assert(asl::uniquely_represented<asl::option<NonZero>>);

 ASL_TEST(option)
 {
-    asl::option<int> int1 = 0;
-    asl::option<int> int2 = 0;
-    asl::option<int> int3 = 1;
-    asl::option<int> int4 = asl::nullopt;
+    const asl::option<int> int1 = 0;
+    const asl::option<int> int2 = 0;
+    const asl::option<int> int3 = 1;
+    const asl::option<int> int4 = asl::nullopt;

    ASL_TEST_EXPECT(asl::hash_value(int1) == asl::hash_value(int2));
    ASL_TEST_EXPECT(asl::hash_value(int1) != asl::hash_value(int3));
    ASL_TEST_EXPECT(asl::hash_value(int1) != asl::hash_value(int4));

-    asl::option<NonZero> noz1{8};
-    asl::option<NonZero> noz2{8};
-    asl::option<NonZero> noz3{9};
-    asl::option<NonZero> noz4 = asl::nullopt;
+    const asl::option<NonZero> noz1{8};
+    const asl::option<NonZero> noz2{8};
+    const asl::option<NonZero> noz3{9};
+    const asl::option<NonZero> noz4 = asl::nullopt;

    ASL_TEST_EXPECT(asl::hash_value(noz1) == asl::hash_value(noz2));
    ASL_TEST_EXPECT(asl::hash_value(noz1) != asl::hash_value(noz3));
@ -208,17 +208,18 @@ ASL_TEST(option)

 static_assert(asl::hashable<asl::status>);

+// NOLINTNEXTLINE(*-cognitive-complexity)
 ASL_TEST(status)
 {
-    asl::status s1 = asl::ok();
-    asl::status s2 = asl::ok();
-    asl::status s3 = asl::internal_error();
-    asl::status s4 = asl::internal_error();
-    asl::status s5 = asl::runtime_error();
-    asl::status s6 = asl::internal_error("Oh, no!");
-    asl::status s7 = asl::internal_error("Oh, no!");
-    asl::status s8 = asl::internal_error("Oh, no");
-    asl::status s9 = asl::runtime_error("Oh, no!");
+    const asl::status s1 = asl::ok();
+    const asl::status s2 = asl::ok();
+    const asl::status s3 = asl::internal_error();
+    const asl::status s4 = asl::internal_error();
+    const asl::status s5 = asl::runtime_error();
+    const asl::status s6 = asl::internal_error("Oh, no!");
+    const asl::status s7 = asl::internal_error("Oh, no!");
+    const asl::status s8 = asl::internal_error("Oh, no");
+    const asl::status s9 = asl::runtime_error("Oh, no!");

    ASL_TEST_EXPECT(asl::hash_value(s1) == asl::hash_value(s2));
    ASL_TEST_EXPECT(asl::hash_value(s3) == asl::hash_value(s4));
@ -244,13 +245,13 @@ static_assert(!asl::hashable<asl::status_or<int*>>);

 ASL_TEST(status_or)
 {
-    asl::status_or<int> s1 = 42;
-    asl::status_or<int> s2 = 42;
-    asl::status_or<int> s3 = 43;
-    asl::status_or<int> s4 = asl::runtime_error();
-    asl::status_or<int> s5 = asl::runtime_error();
-    asl::status_or<int> s6 = asl::runtime_error("Hello");
-    asl::status_or<int> s7 = asl::runtime_error("Hello");
+    const asl::status_or<int> s1 = 42;
+    const asl::status_or<int> s2 = 42;
+    const asl::status_or<int> s3 = 43;
+    const asl::status_or<int> s4 = asl::runtime_error();
+    const asl::status_or<int> s5 = asl::runtime_error();
+    const asl::status_or<int> s6 = asl::runtime_error("Hello");
+    const asl::status_or<int> s7 = asl::runtime_error("Hello");

    ASL_TEST_EXPECT(asl::hash_value(s1) == asl::hash_value(s2));
    ASL_TEST_EXPECT(asl::hash_value(s4) == asl::hash_value(s5));
--- a/asl/io/print.cpp
+++ b/asl/io/print.cpp
@ -18,7 +18,7 @@ public:

    void write(asl::span<const asl::byte> s) override
    {
-        fwrite(s.data(), 1, static_cast<size_t>(s.size()), m_handle);
+        (void)fwrite(s.data(), 1, static_cast<size_t>(s.size()), m_handle);
    }
 };

--- a/asl/logging/logging.cpp
+++ b/asl/logging/logging.cpp
@ -3,14 +3,22 @@
 // SPDX-License-Identifier: BSD-3-Clause

 #include "asl/logging/logging.hpp"
+
+#include "asl/containers/intrusive_list.hpp"
+#include "asl/formatting/format.hpp"
 #include "asl/io/print.hpp"
+#include "asl/io/writer.hpp"
 #include "asl/strings/string_builder.hpp"
+#include "asl/strings/string_view.hpp"
+#include "asl/types/span.hpp"

 // @Todo Don't use internal get_stdout_writer, make console module

+// NOLINTNEXTLINE(*-avoid-non-const-global-variables)
 static asl::log::DefaultLogger<asl::Writer*> g_default_logger{asl::print_internals::get_stdout_writer()};

 // @Todo Protect the loggers list being a mutex
+// NOLINTNEXTLINE(*-avoid-non-const-global-variables)
 static asl::IntrusiveList<asl::log::Logger> g_loggers(&g_default_logger);

 void asl::log::register_logger(Logger* logger)
@ -56,7 +64,7 @@ void asl::log::log_inner(
    StringWriter msg_writer{};
    asl::format_internals::format(&msg_writer, fmt, args);

-    message m{
+    const message m{
        .level = l,
        .message = msg_writer.as_string_view(),
        .location = sl,
--- a/asl/logging/logging.hpp
+++ b/asl/logging/logging.hpp
@ -48,7 +48,11 @@ class DefaultLogger : public DefaultLoggerBase
    W m_writer;

 public:
-    explicit constexpr DefaultLogger(W&& writer) : m_writer{ASL_FWD(writer)} {}
+    template<typename U>
+    explicit constexpr DefaultLogger(U&& writer)
+        requires constructible_from<W, U&&>
+        : m_writer{std::forward<U>(writer)}
+    {}

    constexpr void log(const message& m) override
    {
@ -74,7 +78,7 @@ void log(level l, const source_location& sl, string_view fmt, const Args&... arg
    }
    else
    {
-        format_internals::type_erased_arg type_erased_args[] = {
+        const format_internals::type_erased_arg type_erased_args[] = {
            format_internals::type_erased_arg(args)...
        };
        log_inner(l, fmt, type_erased_args, sl);
@ -83,9 +87,26 @@ void log(level l, const source_location& sl, string_view fmt, const Args&... arg

 } // namespace asl::log

-// @Todo Compile-time configuration of logging
+#if !defined(ASL_LOG_LEVEL) || ASL_LOG_LEVEL >= 4
+    #define ASL_LOG_DEBUG(...)   ::asl::log::log(::asl::log::kDebug,   ::asl::source_location{}, __VA_ARGS__)
+#else
+    #define ASL_LOG_DEBUG(...)
+#endif

-#define ASL_LOG_DEBUG(...) ::asl::log::log(::asl::log::kDebug, ::asl::source_location{}, __VA_ARGS__)
-#define ASL_LOG_INFO(...) ::asl::log::log(::asl::log::kInfo, ::asl::source_location{}, __VA_ARGS__)
-#define ASL_LOG_WARNING(...) ::asl::log::log(::asl::log::kWarning, ::asl::source_location{}, __VA_ARGS__)
-#define ASL_LOG_ERROR(...) ::asl::log::log(::asl::log::kError, ::asl::source_location{}, __VA_ARGS__)
+#if !defined(ASL_LOG_LEVEL) || ASL_LOG_LEVEL >= 3
+    #define ASL_LOG_INFO(...)    ::asl::log::log(::asl::log::kInfo,    ::asl::source_location{}, __VA_ARGS__)
+#else
+    #define ASL_LOG_DEBUG(...)
+#endif
+
+#if !defined(ASL_LOG_LEVEL) || ASL_LOG_LEVEL >= 2
+    #define ASL_LOG_WARNING(...) ::asl::log::log(::asl::log::kWarning, ::asl::source_location{}, __VA_ARGS__)
+#else
+    #define ASL_LOG_DEBUG(...)
+#endif
+
+#if !defined(ASL_LOG_LEVEL) || ASL_LOG_LEVEL >= 1
+    #define ASL_LOG_ERROR(...)   ::asl::log::log(::asl::log::kError,   ::asl::source_location{}, __VA_ARGS__)
+#else
+    #define ASL_LOG_DEBUG(...)
+#endif
--- a/asl/logging/logging_tests.cpp
+++ b/asl/logging/logging_tests.cpp
@ -2,10 +2,11 @@
 //
 // SPDX-License-Identifier: BSD-3-Clause

-#include "asl/logging/logging.hpp"
-#include "asl/testing/testing.hpp"
-#include "asl/strings/string_builder.hpp"
 #include "asl/base/defer.hpp"
+#include "asl/logging/logging.hpp"
+#include "asl/strings/string_builder.hpp"
+#include "asl/strings/string_view.hpp"
+#include "asl/testing/testing.hpp"

 ASL_TEST(log)
 {
@ -27,6 +28,6 @@ ASL_TEST(custom_writer)
    ASL_LOG_INFO("Hello");
    auto sv = string_writer.as_string_view();

-    ASL_TEST_EXPECT(sv == "[  INFO   ] asl/logging/logging_tests.cpp:27: Hello\n");
+    ASL_TEST_EXPECT(sv == "[  INFO   ] asl/logging/logging_tests.cpp:28: Hello\n");
 }

--- a/asl/memory/BUILD.bazel
+++ b/asl/memory/BUILD.bazel
@ -9,16 +9,27 @@ package(
 cc_library(
    name = "memory",
    hdrs = [
-        "allocator.hpp",
        "layout.hpp",
        "memory.hpp",
    ],
-    srcs = [
-        "allocator.cpp",
-    ],
    deps = [
        "//asl/base",
    ],
    visibility = ["//visibility:public"],
 )

+cc_library(
+    name = "allocator",
+    hdrs = [
+        "allocator.hpp",
+    ],
+    srcs = [
+        "allocator.cpp",
+    ],
+    deps = [
+        "//asl/base",
+        "//asl/memory",
+    ],
+    visibility = ["//visibility:public"],
+)
+
--- a/asl/memory/allocator.cpp
+++ b/asl/memory/allocator.cpp
@ -4,6 +4,7 @@

 #include "asl/memory/allocator.hpp"
 #include "asl/base/assert.hpp"
+#include "asl/base/numeric.hpp"
 #include "asl/memory/layout.hpp"

 #include <cstdlib>
--- a/asl/memory/allocator.hpp
+++ b/asl/memory/allocator.hpp
@ -37,7 +37,22 @@ template<typename T>
 T* alloc_new(allocator auto& a, auto&&... args)
 {
    void* ptr = a.alloc(layout::of<T>());
-    return construct_at<T>(ptr, ASL_FWD(args)...);
+    return construct_at<T>(ptr, std::forward<decltype(args)>(args)...);
+}
+
+template<typename T>
+T* alloc_uninit(allocator auto& a)
+    requires trivially_default_constructible<T>
+{
+    void* ptr = a.alloc(layout::of<T>());
+    return reinterpret_cast<T*>(ptr); // NOLINT(*-reinterpret-cast)
+}
+
+template<typename T>
+T* alloc_uninit_unsafe(allocator auto& a)
+{
+    void* ptr = a.alloc(layout::of<T>());
+    return reinterpret_cast<T*>(ptr); // NOLINT(*-reinterpret-cast)
 }

 template<typename T>
@ -50,13 +65,15 @@ void alloc_delete(allocator auto& a, T* ptr)
 template<typename T>
 constexpr T* alloc_new_default(auto&&... args)
 {
-    return alloc_new<T>(DefaultAllocator{}, ASL_FWD(args)...);
+    DefaultAllocator allocator{};
+    return alloc_new<T>(allocator, std::forward<decltype(args)>(args)...);
 }

 template<typename T>
 void alloc_delete_default(T* ptr)
 {
-    alloc_delete(DefaultAllocator{}, ptr);
+    DefaultAllocator allocator{};
+    alloc_delete(allocator, ptr);
 }

 } // namespace asl
--- a/asl/memory/memory.hpp
+++ b/asl/memory/memory.hpp
@ -9,7 +9,7 @@
 #include "asl/base/utility.hpp"
 #include "asl/memory/layout.hpp"

-constexpr void* operator new(size_t, void* ptr)
+constexpr void* operator new(size_t, void* ptr) noexcept
 {
    return ptr;
 }
@ -17,6 +17,17 @@ constexpr void* operator new(size_t, void* ptr)
 namespace asl
 {

+template<typename T>
+[[nodiscard]]
+constexpr T* address_of(T& obj)
+{
+    return __builtin_addressof(obj);
+}
+
+template<typename T>
+void address_of(const T&& obj) = delete;
+
+[[nodiscard]]
 constexpr isize_t memcmp(const void* a, const void* b, isize_t size)
 {
    return __builtin_memcmp(a, b, static_cast<size_t>(size));
@ -41,7 +52,7 @@ template<typename T, typename... Args>
 constexpr T* construct_at(void* ptr, Args&&... args)
    requires constructible_from<T, Args&&...>
 {
-    return new (ptr) T{ ASL_FWD(args)... };
+    return new (ptr) T{ std::forward<Args>(args)... }; // NOLINT(*-owning-memory)
 }

 template<typename T>
@ -112,7 +123,7 @@ constexpr void relocate_uninit_n(T* to, T* from, isize_t n)
        for (isize_t i = 0; i < n; ++i)
        {
            // NOLINTNEXTLINE(*-pointer-arithmetic)
-            construct_at<T>(to + i, ASL_MOVE(from[i]));
+            construct_at<T>(to + i, std::move(from[i]));
        }
        destroy_n(from, n);
    }
@ -131,7 +142,7 @@ constexpr void relocate_assign_n(T* to, T* from, isize_t n)
        for (isize_t i = 0; i < n; ++i)
        {
            // NOLINTNEXTLINE(*-pointer-arithmetic)
-            to[i] = ASL_MOVE(from[i]);
+            to[i] = std::move(from[i]);
        }
        destroy_n(from, n);
    }
--- a/asl/strings/BUILD.bazel
+++ b/asl/strings/BUILD.bazel
@ -45,6 +45,24 @@ cc_library(
    visibility = ["//visibility:public"],
 )

+cc_library(
+    name = "parse_number",
+    hdrs = [
+        "parse_number.hpp",
+    ],
+    srcs = [
+        "parse_number_float.cpp",
+        "parse_number.cpp",
+    ],
+    deps = [
+        "//asl/base",
+        "//asl/types:status",
+        ":string_view",
+        "//vendor/fast_float",
+    ],
+    visibility = ["//visibility:public"],
+)
+
 [cc_test(
    name = "%s_tests" % name,
    srcs = [
@ -54,6 +72,7 @@ cc_library(
        ":string",
        ":string_builder",
        ":string_view",
+        ":parse_number",
        "//asl/tests:utils",
        "//asl/testing",
    ],
@ -61,4 +80,5 @@ cc_library(
    "string",
    "string_view",
    "string_builder",
+    "parse_number",
 ]]
--- a/asl/strings/parse_number.cpp
+++ b/asl/strings/parse_number.cpp
@ -0,0 +1,162 @@
+// Copyright 2025 Steven Le Rouzic
+//
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include "asl/strings/parse_number.hpp"
+
+namespace asl
+{
+
+bool parse_float_impl(const char** begin, const char* end, float*);
+bool parse_double_impl(const char** begin, const char* end, double*);
+
+} // namespace asl
+
+asl::status_or<asl::parse_number_result<float32_t>> asl::parse_float32(asl::string_view sv)
+{
+    const auto* begin = sv.data();
+    // NOLINTNEXTLINE(*-pointer-arithmetic)
+    const auto* end = begin + sv.size();
+    if (float32_t value{}; parse_float_impl(&begin, end, &value))
+    {
+        return parse_number_result<float32_t>{
+            .value     = value,
+            .remaining = string_view{begin, end},
+        };
+    }
+    return invalid_argument_error();
+}
+
+asl::status_or<asl::parse_number_result<float64_t>> asl::parse_float64(asl::string_view sv)
+{
+    const auto* begin = sv.data();
+    // NOLINTNEXTLINE(*-pointer-arithmetic)
+    const auto* end = begin + sv.size();
+    if (float64_t value{}; parse_double_impl(&begin, end, &value))
+    {
+        return parse_number_result<float64_t>{
+            .value     = value,
+            .remaining = string_view{begin, end},
+        };
+    }
+    return invalid_argument_error();
+}
+
+namespace
+{
+
+constexpr int8_t kBase16Table[256] = {
+    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+     0,  1,  2,  3,  4,  5,  6,  7,  8,  9, -1, -1, -1, -1, -1, -1,
+    -1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+    -1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+};
+
+// @Todo Maybe monomorph this for common bases (2, 16, 10)?
+
+template<typename T>
+asl::status_or<asl::parse_number_result<T>> parse_integer(asl::string_view sv, int base)
+{
+    ASL_ASSERT(base >= 2 && base <= 16);
+
+    if (sv.is_empty()) { return asl::invalid_argument_error(); }
+
+    T value = 0;
+    bool is_negative = false;
+
+    if (asl::is_signed_integer<T> && sv[0] == '-')
+    {
+        is_negative = true;
+        sv = sv.substr(1);
+    }
+
+    isize_t cursor = 0;
+    while (cursor < sv.size())
+    {
+        // NOLINTNEXTLINE(*-array-index)
+        int8_t digit = kBase16Table[static_cast<uint8_t>(sv[cursor])];
+        if (digit < 0 || digit >= base) { break; }
+
+        if (__builtin_mul_overflow(value, static_cast<T>(base), &value))
+        {
+            return asl::invalid_argument_error("overflow");
+        }
+
+        if (asl::is_signed_integer<T> && is_negative)
+        {
+            digit = static_cast<int8_t>(-digit);
+        }
+
+        if (__builtin_add_overflow(value, static_cast<T>(digit), &value))
+        {
+            return asl::invalid_argument_error("overflow");
+        }
+
+        cursor += 1;
+    }
+
+    if (cursor == 0)
+    {
+        return asl::invalid_argument_error();
+    }
+
+    return asl::parse_number_result<T>{
+        .value     = value,
+        .remaining = sv.substr(cursor),
+    };
+}
+
+} // anonymous namespace
+
+asl::status_or<asl::parse_number_result<uint8_t>> asl::parse_uint8(string_view sv, int base)
+{
+    return parse_integer<uint8_t>(sv, base);
+}
+
+asl::status_or<asl::parse_number_result<uint16_t>> asl::parse_uint16(string_view sv, int base)
+{
+    return parse_integer<uint16_t>(sv, base);
+}
+
+asl::status_or<asl::parse_number_result<uint32_t>> asl::parse_uint32(string_view sv, int base)
+{
+    return parse_integer<uint32_t>(sv, base);
+}
+
+asl::status_or<asl::parse_number_result<uint64_t>> asl::parse_uint64(string_view sv, int base)
+{
+    return parse_integer<uint64_t>(sv, base);
+}
+
+asl::status_or<asl::parse_number_result<int8_t>> asl::parse_int8(string_view sv, int base)
+{
+    return parse_integer<int8_t>(sv, base);
+}
+
+asl::status_or<asl::parse_number_result<int16_t>> asl::parse_int16(string_view sv, int base)
+{
+    return parse_integer<int16_t>(sv, base);
+}
+
+asl::status_or<asl::parse_number_result<int32_t>> asl::parse_int32(string_view sv, int base)
+{
+    return parse_integer<int32_t>(sv, base);
+}
+
+asl::status_or<asl::parse_number_result<int64_t>> asl::parse_int64(string_view sv, int base)
+{
+    return parse_integer<int64_t>(sv, base);
+}
+
--- a/asl/strings/parse_number.hpp
+++ b/asl/strings/parse_number.hpp
@ -0,0 +1,35 @@
+// Copyright 2025 Steven Le Rouzic
+//
+// SPDX-License-Identifier: BSD-3-Clause
+
+#pragma once
+
+#include "asl/types/status_or.hpp"
+#include "asl/strings/string_view.hpp"
+#include "asl/base/float.hpp"
+
+namespace asl
+{
+
+template<typename T>
+struct parse_number_result
+{
+    T value;
+    string_view remaining;
+};
+
+status_or<parse_number_result<float32_t>> parse_float32(string_view);
+status_or<parse_number_result<float64_t>> parse_float64(string_view);
+
+status_or<parse_number_result<uint8_t>>  parse_uint8(string_view, int base = 10);
+status_or<parse_number_result<uint16_t>> parse_uint16(string_view, int base = 10);
+status_or<parse_number_result<uint32_t>> parse_uint32(string_view, int base = 10);
+status_or<parse_number_result<uint64_t>> parse_uint64(string_view, int base = 10);
+
+status_or<parse_number_result<int8_t>>  parse_int8(string_view, int base = 10);
+status_or<parse_number_result<int16_t>> parse_int16(string_view, int base = 10);
+status_or<parse_number_result<int32_t>> parse_int32(string_view, int base = 10);
+status_or<parse_number_result<int64_t>> parse_int64(string_view, int base = 10);
+
+} // namespace asl
+
--- a/asl/strings/parse_number_float.cpp
+++ b/asl/strings/parse_number_float.cpp
@ -0,0 +1,35 @@
+// Copyright 2025 Steven Le Rouzic
+//
+// SPDX-License-Identifier: BSD-3-Clause
+
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Weverything"
+#include <fast_float.h>
+#pragma clang diagnostic pop
+
+// We need to isolate fast_float.h completely from asl
+// because it conflicts with our redefinitions of things
+// from the STL. In this case it's operator new, but there
+// might be other conflicts.
+
+#pragma clang diagnostic ignored "-Wmissing-prototypes"
+
+namespace asl
+{
+
+extern bool parse_float_impl(const char** begin, const char* end, float* value)
+{
+    auto res = fast_float::from_chars(*begin, end, *value);
+    *begin = res.ptr;
+    return res.ec == std::errc{};
+}
+
+extern bool parse_double_impl(const char** begin, const char* end, double* value)
+{
+    auto res = fast_float::from_chars(*begin, end, *value);
+    *begin = res.ptr;
+    return res.ec == std::errc{};
+}
+
+} // namespace asl
+
--- a/asl/strings/parse_number_integer_table.py
+++ b/asl/strings/parse_number_integer_table.py
@ -0,0 +1,24 @@
+a = ord('a')
+f = ord('f')
+A = ord('A')
+F = ord('F')
+n0 = ord('0')
+n9 = ord('9')
+
+output = ""
+
+for i in range(0, 16):
+    for j in range(0, 16):
+        v = i * 16 + j
+        n = -1
+        if v >= a and v <= f:
+            n = v - a + 10
+        elif v >= A and v <= F:
+            n = v - A + 10
+        elif v >= n0 and v <= n9:
+            n = v - n0
+        output += f"{n:>2}, "
+    output += "\n"
+
+print(output)
+
--- a/asl/strings/parse_number_tests.cpp
+++ b/asl/strings/parse_number_tests.cpp
@ -0,0 +1,201 @@
+// Copyright 2025 Steven Le Rouzic
+//
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include "asl/strings/parse_number.hpp"
+#include "asl/base/numeric.hpp"
+#include "asl/testing/testing.hpp"
+
+ASL_TEST(parse_float_error)
+{
+    const asl::string_view sv = "this is not a number lmao";
+    auto res = asl::parse_float32(sv);
+    ASL_TEST_EXPECT(!res.ok());
+}
+
+ASL_TEST(parse_float_empty)
+{
+    const asl::string_view sv = "";
+    auto res = asl::parse_float32(sv);
+    ASL_TEST_EXPECT(!res.ok());
+}
+
+ASL_TEST(parse_float_simple)
+{
+    const asl::string_view sv = "3.1415";
+    auto res = asl::parse_float32(sv);
+    ASL_TEST_EXPECT(res.ok());
+    ASL_TEST_EXPECT(asl::are_nearly_equal(res.value().value, 3.1415F));
+    ASL_TEST_EXPECT(res.value().remaining.size() == 0);
+}
+
+ASL_TEST(parse_float_integer)
+{
+    const asl::string_view sv = "31415";
+    auto res = asl::parse_float32(sv);
+    ASL_TEST_EXPECT(res.ok());
+    ASL_TEST_EXPECT(res.value().value == 31415.0F);
+    ASL_TEST_EXPECT(res.value().remaining.size() == 0);
+}
+
+ASL_TEST(parse_float_scientific)
+{
+    const asl::string_view sv = "314.15e-2";
+    auto res = asl::parse_float32(sv);
+    ASL_TEST_EXPECT(res.ok());
+    ASL_TEST_EXPECT(asl::are_nearly_equal(res.value().value, 3.1415F));
+    ASL_TEST_EXPECT(res.value().remaining.size() == 0);
+}
+
+ASL_TEST(parse_float_suffix)
+{
+    const asl::string_view sv = "3.1415 yoyoyo";
+    auto res = asl::parse_float32(sv);
+    ASL_TEST_EXPECT(res.ok());
+    ASL_TEST_EXPECT(asl::are_nearly_equal(res.value().value, 3.1415F));
+    ASL_TEST_EXPECT(res.value().remaining == " yoyoyo");
+}
+
+ASL_TEST(parse_int)
+{
+    const asl::string_view sv = "926473";
+    auto res = asl::parse_uint32(sv);
+    ASL_TEST_EXPECT(res.ok());
+    ASL_TEST_EXPECT(res.value().value == 926473);
+    ASL_TEST_EXPECT(res.value().remaining.is_empty());
+}
+
+ASL_TEST(parse_int_negative)
+{
+    const asl::string_view sv = "-926473";
+    auto res = asl::parse_int32(sv);
+    ASL_TEST_EXPECT(res.ok());
+    ASL_TEST_EXPECT(res.value().value == -926473);
+    ASL_TEST_EXPECT(res.value().remaining.is_empty());
+}
+
+ASL_TEST(parse_int_suffix)
+{
+    const asl::string_view sv = "926473 what's this then";
+    auto res = asl::parse_uint32(sv);
+    ASL_TEST_EXPECT(res.ok());
+    ASL_TEST_EXPECT(res.value().value == 926473);
+    ASL_TEST_EXPECT(res.value().remaining == " what's this then");
+}
+
+ASL_TEST(parse_uint_with_minus)
+{
+    const asl::string_view sv = "-926473";
+    auto res = asl::parse_uint32(sv);
+    ASL_TEST_EXPECT(!res.ok());
+}
+
+ASL_TEST(parse_int_with_only_minus)
+{
+    const asl::string_view sv = "-@";
+    auto res = asl::parse_int32(sv);
+    ASL_TEST_EXPECT(!res.ok());
+}
+
+ASL_TEST(parse_uint_invalid)
+{
+    const asl::string_view sv = "abcd";
+    auto res = asl::parse_uint32(sv);
+    ASL_TEST_EXPECT(!res.ok());
+}
+
+ASL_TEST(parse_uint_empty)
+{
+    const asl::string_view sv = "";
+    auto res = asl::parse_uint32(sv);
+    ASL_TEST_EXPECT(!res.ok());
+}
+
+ASL_TEST(parse_uint_overflow)
+{
+    ASL_TEST_EXPECT(!asl::parse_uint16("80000").ok());
+    ASL_TEST_EXPECT(!asl::parse_uint16("65536").ok());
+}
+
+ASL_TEST(parse_uint16_max)
+{
+    const asl::string_view sv = "65535";
+    auto res = asl::parse_uint16(sv);
+    ASL_TEST_EXPECT(res.ok());
+    ASL_TEST_EXPECT(res.value().value == 65535);
+    ASL_TEST_EXPECT(res.value().remaining.is_empty());
+}
+
+ASL_TEST(parse_uint16_zero)
+{
+    const asl::string_view sv = "0";
+    auto res = asl::parse_uint16(sv);
+    ASL_TEST_EXPECT(res.ok());
+    ASL_TEST_EXPECT(res.value().value == 0);
+    ASL_TEST_EXPECT(res.value().remaining.is_empty());
+}
+
+ASL_TEST(parse_uint16_zeros)
+{
+    const asl::string_view sv = "00000";
+    auto res = asl::parse_uint16(sv);
+    ASL_TEST_EXPECT(res.ok());
+    ASL_TEST_EXPECT(res.value().value == 0);
+    ASL_TEST_EXPECT(res.value().remaining.is_empty());
+}
+
+ASL_TEST(parse_int_overflow)
+{
+    ASL_TEST_EXPECT(!asl::parse_int16("80000").ok());
+    ASL_TEST_EXPECT(!asl::parse_int16("40000").ok());
+    ASL_TEST_EXPECT(!asl::parse_int16("32768").ok());
+    ASL_TEST_EXPECT(!asl::parse_int16("-80000").ok());
+    ASL_TEST_EXPECT(!asl::parse_int16("-40000").ok());
+    ASL_TEST_EXPECT(!asl::parse_int16("-32769").ok());
+}
+
+ASL_TEST(parse_int16_max)
+{
+    const asl::string_view sv = "32767";
+    auto res = asl::parse_int16(sv);
+    ASL_TEST_EXPECT(res.ok());
+    ASL_TEST_EXPECT(res.value().value == 32767);
+    ASL_TEST_EXPECT(res.value().remaining.is_empty());
+}
+
+ASL_TEST(parse_int16_min)
+{
+    const asl::string_view sv = "-32768";
+    auto res = asl::parse_int16(sv);
+    ASL_TEST_EXPECT(res.ok());
+    ASL_TEST_EXPECT(res.value().value == -32768);
+    ASL_TEST_EXPECT(res.value().remaining.is_empty());
+}
+
+ASL_TEST(parse_hex)
+{
+    const asl::string_view sv = "1000a";
+    auto res = asl::parse_uint32(sv, 16);
+    ASL_TEST_EXPECT(res.ok());
+    ASL_TEST_EXPECT(res.value().value == 65546);
+    ASL_TEST_EXPECT(res.value().remaining.is_empty());
+}
+
+ASL_TEST(parse_bin)
+{
+    const asl::string_view sv = "101010";
+    auto res = asl::parse_uint32(sv, 2);
+    ASL_TEST_EXPECT(res.ok());
+    ASL_TEST_EXPECT(res.value().value == 42);
+    ASL_TEST_EXPECT(res.value().remaining.is_empty());
+}
+
+ASL_TEST(parse_oct)
+{
+    const asl::string_view sv = "644";
+    auto res = asl::parse_uint32(sv, 8);
+    ASL_TEST_EXPECT(res.ok());
+    ASL_TEST_EXPECT(res.value().value == 6 * 64 + 4 * 8 + 4);
+    ASL_TEST_EXPECT(res.value().remaining.is_empty());
+}
+
--- a/asl/strings/string.hpp
+++ b/asl/strings/string.hpp
@ -11,12 +11,12 @@ namespace asl
 {

 template<allocator Allocator = DefaultAllocator>
-class string
+class string : protected buffer<char, Allocator>
 {
-    buffer<char, Allocator> m_buffer;
+    using Base = buffer<char, Allocator>;

-    explicit constexpr string(buffer<char, Allocator>&& buffer) :
-        m_buffer{ASL_MOVE(buffer)}
+    explicit constexpr string(buffer<char, Allocator>&& b) :
+        Base{std::move(b)}
    {}

    template<allocator A>
@ -24,38 +24,36 @@ class string

 public:
    constexpr string() requires default_constructible<Allocator> = default;
-    explicit constexpr string(Allocator allocator) : m_buffer{ASL_MOVE(allocator)} {}

-    // NOLINTNEXTLINE(*-explicit-conversions)
+    explicit constexpr string(Allocator allocator)
+        : Base{std::move(allocator)}
+    {}
+
+    // NOLINTNEXTLINE(*explicit*)
    constexpr string(string_view sv)
        requires default_constructible<Allocator>
-        : m_buffer{sv.as_span()}
+        : Base{sv.as_span()}
    {}

    constexpr string(string_view sv, Allocator allocator)
-        : m_buffer{sv.as_span(), ASL_MOVE(allocator)}
+        : Base{sv.as_span(), std::move(allocator)}
    {}

-    constexpr ~string() = default;
+    using Base::size;

-    constexpr string(const string&) requires copy_constructible<Allocator> = default;
-    constexpr string(string&&) = default;
+    using Base::is_empty;

-    constexpr string& operator=(const string&) requires copy_assignable<Allocator> = default;
-    constexpr string& operator=(string&&) = default;
+    [[nodiscard]] constexpr const char* data() const { return Base::data(); }

-    constexpr isize_t size() const { return m_buffer.size(); }
-    constexpr const char* data() const { return m_buffer.data(); }
-
-    // NOLINTNEXTLINE(*-explicit-conversions)
+    // NOLINTNEXTLINE(*explicit*)
    constexpr operator string_view() const
    {
        return as_string_view();
    }

-    constexpr string_view as_string_view() const
+    [[nodiscard]] constexpr string_view as_string_view() const
    {
-        auto span = m_buffer.as_span();
+        auto span = Base::as_span();
        return string_view{span.data(), span.size()};
    }

--- a/asl/strings/string_builder.hpp
+++ b/asl/strings/string_builder.hpp
@ -20,7 +20,7 @@ class StringBuilder

 public:
    constexpr StringBuilder() requires default_constructible<Allocator> = default;
-    explicit constexpr StringBuilder(Allocator allocator) : m_buffer{ASL_MOVE(allocator)} {}
+    explicit constexpr StringBuilder(Allocator allocator) : m_buffer{std::move(allocator)} {}

    constexpr ~StringBuilder() = default;

@ -30,7 +30,7 @@ public:
    constexpr StringBuilder& operator=(const StringBuilder&) requires copy_assignable<Allocator> = default;
    constexpr StringBuilder& operator=(StringBuilder&&) = default;

-    constexpr string_view as_string_view() const
+    [[nodiscard]] constexpr string_view as_string_view() const
    {
        auto span = m_buffer.as_span();
        return string_view{span.data(), span.size()};
@ -44,23 +44,23 @@ public:
    auto push(this auto&& self, string_view sv) -> decltype(self)
        requires (!is_const<un_ref_t<decltype(self)>>)
    {
-        isize_t old_size = self.m_buffer.size();
-        self.m_buffer.resize_zero(old_size + sv.size());
+        const isize_t old_size = self.m_buffer.size();
+        self.m_buffer.resize_uninit(old_size + sv.size());
        // NOLINTNEXTLINE(*-pointer-arithmetic)
        asl::memcpy(self.m_buffer.data() + old_size, sv.data(), sv.size());
-        return ASL_FWD(self);
+        return std::forward<decltype(self)>(self);
    }

    auto push(this auto&& self, char c) -> decltype(self)
        requires (!is_const<un_ref_t<decltype(self)>>)
    {
        self.m_buffer.push(c);
-        return ASL_FWD(self);
+        return std::forward<decltype(self)>(self);
    }

    string<Allocator> finish() &&
    {
-        return string<Allocator>{ASL_MOVE(m_buffer)};
+        return string<Allocator>{std::move(m_buffer)};
    }

    template<allocator StringAllocator = Allocator>
@ -73,7 +73,7 @@ public:
    template<allocator StringAllocator = Allocator>
    string<StringAllocator> as_string(Allocator allocator) const
    {
-        return string<StringAllocator>{as_string_view(), ASL_MOVE(allocator)};
+        return string<StringAllocator>{as_string_view(), std::move(allocator)};
    }
 };

@ -86,7 +86,7 @@ class StringWriter : public asl::Writer

 public:
    constexpr StringWriter() requires default_constructible<Allocator> = default;
-    explicit constexpr StringWriter(Allocator allocator) : m_builder{ASL_MOVE(allocator)} {}
+    explicit constexpr StringWriter(Allocator allocator) : m_builder{std::move(allocator)} {}

    constexpr ~StringWriter() override = default;

@ -98,17 +98,18 @@ public:

    void write(span<const byte> str) override
    {
+        // NOLINTNEXTLINE(*-reinterpret-cast)
        m_builder.push(string_view{reinterpret_cast<const char*>(str.data()), str.size()});
    }

-    constexpr string_view as_string_view() const
+    [[nodiscard]] constexpr string_view as_string_view() const
    {
        return m_builder.as_string_view();
    }

    string<Allocator> finish() &&
    {
-        return ASL_MOVE(m_builder).finish();
+        return std::move(m_builder).finish();
    }

    template<allocator StringAllocator = Allocator>
@ -121,7 +122,7 @@ public:
    template<allocator StringAllocator = Allocator>
    string<StringAllocator> as_string(Allocator allocator) const
    {
-        return m_builder.as_string(ASL_MOVE(allocator));
+        return m_builder.as_string(std::move(allocator));
    }
 };

@ -133,15 +134,15 @@ string<Allocator> format_to_string(string_view fmt, const formattable auto&... a
 {
    StringWriter writer{};
    format(&writer, fmt, args...);
-    return ASL_MOVE(writer).finish();
+    return std::move(writer).finish();
 }

 template<allocator Allocator = DefaultAllocator>
 string<Allocator> format_to_string(Allocator allocator, string_view fmt, const formattable auto&... args)
 {
-    StringWriter writer{ASL_MOVE(allocator)};
+    StringWriter writer{std::move(allocator)};
    format(&writer, fmt, args...);
-    return ASL_MOVE(writer).finish();
+    return std::move(writer).finish();
 }

 } // namespace asl
--- a/asl/strings/string_builder_tests.cpp
+++ b/asl/strings/string_builder_tests.cpp
@ -14,13 +14,13 @@ ASL_TEST(string_builder)

    ASL_TEST_EXPECT(b.as_string_view() == "abcdefg");

-    asl::string s = b.as_string();
+    const asl::string s = b.as_string();
    ASL_TEST_EXPECT(s == "abcdefg");
 }

 ASL_TEST(string_builder_rvalue)
 {
-    asl::string s = asl::StringBuilder{}.push('a').push("bcdef").push('g').finish();
+    const asl::string s = asl::StringBuilder{}.push('a').push("bcdef").push('g').finish();

    ASL_TEST_EXPECT(s == "abcdefg");
 }
--- a/asl/strings/string_tests.cpp
+++ b/asl/strings/string_tests.cpp
@ -8,7 +8,7 @@

 ASL_TEST(default)
 {
-    asl::string s;
+    const asl::string s;
    ASL_TEST_ASSERT(s.size() == 0);
    ASL_TEST_ASSERT(s.as_string_view().size() == 0);
    ASL_TEST_ASSERT(s == ""_sv);
@ -17,7 +17,7 @@ ASL_TEST(default)

 ASL_TEST(from_string_view)
 {
-    asl::string s = "hello"_sv;
+    const asl::string s = "hello"_sv;
    ASL_TEST_ASSERT(s.size() == 5);
    ASL_TEST_ASSERT(s == "hello"_sv);
 }
--- a/asl/strings/string_view.hpp
+++ b/asl/strings/string_view.hpp
@ -12,6 +12,7 @@
 namespace asl
 {

+// NOLINTBEGIN(*-convert-member-functions-to-static)
 class string_view
 {
    const char* m_data{};
@ -20,17 +21,24 @@ class string_view
 public:
    constexpr string_view() = default;

-    constexpr string_view(nullptr_t) : string_view() {} // NOLINT(*-explicit-conversions)
+    constexpr string_view(nullptr_t) : string_view() {} // NOLINT(*explicit*)

    constexpr string_view(const char* data, isize_t size)
        : m_data{data}
        , m_size{size}
    {}

+    constexpr string_view(const char* begin, const char* end)
+        : m_data{begin}
+        , m_size{end - begin}
+    {
+        ASL_ASSERT(begin <= end);
+    }
+
    template<isize_t kSize>
-    constexpr string_view(const char (&str)[kSize]) // NOLINT(*-explicit-conversions)
+    constexpr string_view(const char (&str)[kSize]) // NOLINT(*explicit*)
        requires (kSize >= 1)
-        : m_data{str}
+        : m_data{static_cast<const char*>(str)}
        , m_size{kSize - 1}
    {
        ASL_ASSERT(m_data[kSize - 1] == '\0'); // NOLINT(*-pointer-arithmetic)
@ -38,7 +46,7 @@ public:

    static constexpr string_view from_zstr(const char* str)
    {
-        return string_view(str, asl::strlen(str));
+        return {str, asl::strlen(str)};
    }

    constexpr string_view(const string_view&) = default;
@ -49,51 +57,69 @@ public:

    ~string_view() = default;

-    constexpr isize_t size() const { return m_size; }
-
-    constexpr bool is_empty() const { return m_size == 0; }
-
-    constexpr const char* data() const { return m_data; }
-
-    constexpr contiguous_iterator<const char> begin() const { return contiguous_iterator{m_data}; }
-
-    // NOLINTNEXTLINE(*-pointer-arithmetic)
-    constexpr contiguous_iterator<const char> end() const { return contiguous_iterator{m_data + m_size}; }
-
-    constexpr span<const char> as_span() const { return span<const char>(m_data, m_size); }
-
-    constexpr char operator[](isize_t i) const
+    [[nodiscard]] constexpr isize_t size(this string_view self)
    {
-        ASL_ASSERT(i >= 0 && i < m_size);
-        return m_data[i]; // NOLINT(*-pointer-arithmetic)
+        return self.m_size;
    }

-    constexpr string_view substr(isize_t offset, isize_t size) const
+    [[nodiscard]] constexpr bool is_empty(this string_view self)
    {
-        ASL_ASSERT(offset >= 0 && size >= 0 && offset + size <= m_size);
-        return string_view{m_data + offset, size}; // NOLINT(*-pointer-arithmetic)
+        return self.m_size == 0;
    }

-    constexpr string_view substr(isize_t offset) const
+    [[nodiscard]] constexpr const char* data(this string_view self)
    {
-        ASL_ASSERT(offset >= 0 && offset <= m_size);
-        return string_view{m_data + offset, m_size - offset}; // NOLINT(*-pointer-arithmetic)
+        return self.m_data;
    }

-    constexpr string_view first(isize_t size) const
+    [[nodiscard]] constexpr contiguous_iterator<const char> begin(this string_view self)
    {
-        return substr(0, size);
+        return contiguous_iterator{self.m_data};
    }

-    constexpr string_view last(isize_t size) const
+    [[nodiscard]] constexpr contiguous_iterator<const char> end(this string_view self)
    {
-        return substr(m_size - size);
+        // NOLINTNEXTLINE(*-pointer-arithmetic)
+        return contiguous_iterator{self.m_data + self.m_size};
    }

-    constexpr bool operator==(string_view other) const
+    [[nodiscard]] constexpr span<const char> as_span(this string_view self)
    {
-        if (m_size != other.m_size) { return false; }
-        return memcmp(m_data, other.m_data, m_size) == 0;
+        return {self.m_data, self.m_size};
+    }
+
+    [[nodiscard]] constexpr char operator[](this string_view self, isize_t i)
+    {
+        ASL_ASSERT(i >= 0 && i < self.m_size);
+        return self.m_data[i]; // NOLINT(*-pointer-arithmetic)
+    }
+
+    [[nodiscard]] constexpr string_view substr(this string_view self, isize_t offset, isize_t size)
+    {
+        ASL_ASSERT(offset >= 0 && size >= 0 && offset + size <= self.m_size);
+        return string_view{self.m_data + offset, size}; // NOLINT(*-pointer-arithmetic)
+    }
+
+    [[nodiscard]] constexpr string_view substr(this string_view self, isize_t offset)
+    {
+        ASL_ASSERT(offset >= 0 && offset <= self.m_size);
+        return string_view{self.m_data + offset, self.m_size - offset}; // NOLINT(*-pointer-arithmetic)
+    }
+
+    [[nodiscard]] constexpr string_view first(this string_view self, isize_t size)
+    {
+        return self.substr(0, size);
+    }
+
+    [[nodiscard]] constexpr string_view last(this string_view self, isize_t size)
+    {
+        return self.substr(self.m_size - size);
+    }
+
+    constexpr bool operator==(this string_view self, string_view other)
+    {
+        if (self.m_size != other.m_size) { return false; }
+        return asl::memcmp(self.m_data, other.m_data, self.m_size) == 0;
    }

    template<typename H>
@ -102,10 +128,11 @@ public:
        return H::combine(H::combine_contiguous(h, as_bytes(sv.as_span())), sv.size());
    }
 };
+// NOLINTEND(*-convert-member-functions-to-static)

 } // namespace asl

 constexpr asl::string_view operator ""_sv(const char* s, size_t len)
 {
-    return asl::string_view(s, static_cast<isize_t>(len));
+    return {s, static_cast<isize_t>(len)};
 }
--- a/asl/strings/string_view_tests.cpp
+++ b/asl/strings/string_view_tests.cpp
@ -10,20 +10,20 @@ static_assert(asl::trivially_copy_constructible<asl::string_view>);

 ASL_TEST(default)
 {
-    asl::string_view s1;
+    const asl::string_view s1;
    ASL_TEST_EXPECT(s1.is_empty());

-    asl::string_view s2 = nullptr;
+    const asl::string_view s2 = nullptr;
    ASL_TEST_EXPECT(s2.is_empty());
 }

 ASL_TEST(from_literal)
 {
-    asl::string_view s1 = "Hello"_sv;
+    const asl::string_view s1 = "Hello"_sv;
    ASL_TEST_ASSERT(s1.size() == 5);
    ASL_TEST_EXPECT(asl::memcmp(s1.data(), "Hello", 5) == 0);

-    asl::string_view s2 = ""_sv;
+    const asl::string_view s2 = ""_sv;
    ASL_TEST_EXPECT(s2.is_empty());
 }

@ -47,7 +47,7 @@ ASL_TEST(from_zstr)

 ASL_TEST(substr1)
 {
-    asl::string_view s1 = "abcd";
+    const asl::string_view s1 = "abcd";

    asl::string_view s2 = s1.substr(0);
    ASL_TEST_ASSERT(s2.size() == 4);
@ -63,7 +63,7 @@ ASL_TEST(substr1)

 ASL_TEST(substr2)
 {
-    asl::string_view s1 = "abcd";
+    const asl::string_view s1 = "abcd";

    asl::string_view s2 = s1.substr(0, 4);
    ASL_TEST_ASSERT(s2.size() == 4);
@ -82,7 +82,7 @@ ASL_TEST(substr2)

 ASL_TEST(first)
 {
-    asl::string_view s1 = "abcd";
+    const asl::string_view s1 = "abcd";

    asl::string_view s2 = s1.first(0);
    ASL_TEST_ASSERT(s2.size() == 0);
@ -98,7 +98,7 @@ ASL_TEST(first)

 ASL_TEST(last)
 {
-    asl::string_view s1 = "abcd";
+    const asl::string_view s1 = "abcd";

    asl::string_view s2 = s1.last(0);
    ASL_TEST_ASSERT(s2.size() == 0);
--- a/asl/testing/testing.cpp
+++ b/asl/testing/testing.cpp
@ -4,37 +4,51 @@

 #include "asl/testing/testing.hpp"

+#include "asl/base/assert.hpp"
+#include "asl/base/meta.hpp"
+#include "asl/base/utility.hpp"
 #include "asl/io/print.hpp"

-static asl::testing::Test* g_head = nullptr;
-static asl::testing::Test* g_tail = nullptr;
+namespace
+{
+
+struct TestingState
+{
+    asl::testing::Test* head = nullptr;
+    asl::testing::Test* tail = nullptr;
+
+    bool current_test_fail = false;
+};
+
+}  // namespace
+
+// NOLINTNEXTLINE(*-avoid-non-const-global-variables)
+static TestingState g_state{};

 void asl::testing::register_test(Test* test)
 {
-    if (g_head == nullptr && g_tail == nullptr)
+    if (g_state.head == nullptr && g_state.tail == nullptr)
    {
-        g_head = test;
-        g_tail = test;
+        g_state.head = test;
+        g_state.tail = test;
    }
    else
    {
-        g_tail->m_next = test;
-        test->m_prev = asl::exchange(g_tail, test);
+        g_state.tail->m_next = test;
+        test->m_prev = asl::exchange(g_state.tail, test);
    }
 }

-static bool g_current_test_fail = false;
-
 void asl::testing::report_failure(const char* msg, const asl::source_location& sl)
 {
    asl::eprint("--------------------------------------------------------------\n");
    asl::eprint("Test assertion failed at {}, line {}:\n", sl.file, sl.line);
    asl::eprint("    {}\n", msg);
    asl::eprint("--------------------------------------------------------------\n");
-    g_current_test_fail = true;
+    g_state.current_test_fail = true;
 }

-static void report_assert_failure(const char* msg, const asl::source_location& sl, void*)
+static void report_assert_failure(const char* msg, const asl::source_location& sl, void* /* userdata */)
 {
    asl::eprint("------------------------------------------------------------\n");
    asl::eprint("Assertion failure at {}, line {}:\n", sl.file, sl.line);
@ -55,24 +69,28 @@ int main([[maybe_unused]] int argc, [[maybe_unused]] char* argv[])

    asl::testing::Test* failed_head = nullptr;

-    for (auto* it = g_head; it != nullptr; it = it->m_next)
+    for (auto* it = g_state.head; it != nullptr;)
    {
        asl::eprint(GREEN("[ RUN      ]") " {}\n", it->m_case_name);

-        g_current_test_fail = false;
+        g_state.current_test_fail = false;
        it->m_fn();

-        if (!g_current_test_fail)
+        if (!g_state.current_test_fail)
        {
            asl::eprint(GREEN("[       OK ]") " {}\n", it->m_case_name);
            pass += 1;
+            it = it->m_next;
        }
        else
        {
            asl::eprint(RED("[  FAILED  ]") " {}\n", it->m_case_name);
            fail += 1;

-            it->m_next = asl::exchange(failed_head, it);
+            auto* this_test = it;
+            it = it->m_next;
+
+            this_test->m_next = asl::exchange(failed_head, this_test);
        }
    }

--- a/asl/testing/testing.hpp
+++ b/asl/testing/testing.hpp
@ -4,7 +4,7 @@

 #pragma once

-#include "asl/base/utility.hpp"
+#include "asl/base/meta.hpp"

 namespace asl::testing
 {
@ -35,7 +35,8 @@ struct Test
 } // namespace asl::testing

 #define ASL_TEST(CASE)                              \
-    static void asl_test_fn_##CASE();               \
+    static void asl_test_fn_##CASE(); /* NOLINT */  \
+    /* NOLINTNEXTLINE */                            \
    static ::asl::testing::Test asl_test_##CASE(    \
        #CASE,                                      \
        asl_test_fn_##CASE);                        \
@ -45,6 +46,6 @@ struct Test
    if (EXPR) {}              \
    else { ::asl::testing::report_failure(#EXPR); return; }

-#define ASL_TEST_EXPECT(EXPR) \
-    if (EXPR) {}              \
-    else { ::asl::testing::report_failure(#EXPR); }
+#define ASL_TEST_EXPECT(...) \
+    if (__VA_ARGS__) {}      \
+    else { ::asl::testing::report_failure(#__VA_ARGS__); }
--- a/asl/tests/BUILD.bazel
+++ b/asl/tests/BUILD.bazel
@ -9,10 +9,12 @@ package(
 cc_library(
    name = "utils",
    hdrs = [
+        "counting_allocator.hpp",
        "types.hpp",
    ],
    deps = [
        "//asl/base",
+        "//asl/memory:allocator",
    ],
    visibility = ["//asl:__subpackages__"],
 )
--- a/asl/tests/counting_allocator.hpp
+++ b/asl/tests/counting_allocator.hpp
@ -0,0 +1,48 @@
+// Copyright 2025 Steven Le Rouzic
+//
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include "asl/memory/allocator.hpp"
+
+struct CountingAllocator
+{
+    struct Stats
+    {
+        isize_t alloc_count{};
+        isize_t realloc_count{};
+        isize_t dealloc_count{};
+        isize_t alive_bytes{};
+
+        [[nodiscard]] constexpr isize_t any_alloc_count() const
+        {
+            return alloc_count + realloc_count;
+        }
+    };
+
+    Stats* stats;
+
+    [[nodiscard]]
+    void* alloc(const asl::layout& layout) const
+    {
+        stats->alloc_count += 1;
+        stats->alive_bytes += layout.size;
+        return asl::GlobalHeap::alloc(layout);
+    }
+
+    void* realloc(void* ptr, const asl::layout& old, const asl::layout& new_layout) const
+    {
+        stats->realloc_count += 1;
+        stats->alive_bytes += new_layout.size - old.size;
+        return asl::GlobalHeap::realloc(ptr, old, new_layout);
+    }
+
+    void dealloc(void* ptr, const asl::layout& layout) const
+    {
+        stats->dealloc_count += 1;
+        stats->alive_bytes -= layout.size;
+        asl::GlobalHeap::dealloc(ptr, layout);
+    }
+
+    constexpr bool operator==(const CountingAllocator&) const { return true; }
+};
+static_assert(asl::allocator<CountingAllocator>);
--- a/asl/tests/types.hpp
+++ b/asl/tests/types.hpp
@ -77,7 +77,7 @@ struct DestructorObserver
    {
        if (this != &other)
        {
-            destroyed = asl::exchange(other.destroyed, nullptr);
+            asl::swap(destroyed, other.destroyed);
        }
        return *this;
    }
--- a/asl/types/BUILD.bazel
+++ b/asl/types/BUILD.bazel
@ -6,6 +6,18 @@ package(
    default_applicable_licenses = ["//:license"],
 )

+cc_library(
+    name = "array",
+    hdrs = [
+        "array.hpp",
+    ],
+    deps = [
+        "//asl/base",
+        "//asl/types:span",
+    ],
+    visibility = ["//visibility:public"],
+)
+
 cc_library(
    name = "box",
    hdrs = [
@ -14,6 +26,7 @@ cc_library(
    deps = [
        "//asl/base",
        "//asl/memory",
+        "//asl/memory:allocator",
        "//asl/hashing",
    ],
    visibility = ["//visibility:public"],
@ -78,6 +91,61 @@ cc_library(
    visibility = ["//visibility:public"],
 )

+cc_library(
+    name = "function",
+    hdrs = [
+        "function.hpp",
+    ],
+    deps = [
+        "//asl/base",
+        "//asl/memory",
+        "//asl/memory:allocator",
+    ],
+    visibility = ["//visibility:public"],
+)
+
+cc_library(
+    name = "function_ref",
+    hdrs = [
+        "function_ref.hpp",
+    ],
+    deps = [
+        "//asl/base",
+        "//asl/memory",
+    ],
+    visibility = ["//visibility:public"],
+)
+
+cc_test(
+    name = "function_tests",
+    srcs = ["function_tests.cpp"],
+    deps = [
+        "//asl/tests:utils",
+        "//asl/testing",
+        "//asl/types:function",
+    ],
+)
+
+cc_test(
+    name = "function_ref_tests",
+    srcs = ["function_ref_tests.cpp"],
+    deps = [
+        "//asl/tests:utils",
+        "//asl/testing",
+        "//asl/types:function_ref",
+    ],
+)
+
+cc_test(
+    name = "array_tests",
+    srcs = ["array_tests.cpp"],
+    deps = [
+        "//asl/tests:utils",
+        "//asl/testing",
+        "//asl/types:array",
+    ],
+)
+
 cc_test(
    name = "box_tests",
    srcs = ["box_tests.cpp"],
--- a/asl/types/array.hpp
+++ b/asl/types/array.hpp
@ -0,0 +1,70 @@
+// Copyright 2025 Steven Le Rouzic
+//
+// SPDX-License-Identifier: BSD-3-Clause
+
+#pragma once
+
+#include "asl/base/assert.hpp"
+#include "asl/base/meta.hpp"
+#include "asl/base/utility.hpp"
+#include "asl/types/span.hpp"
+
+namespace asl
+{
+
+template<is_object T, isize_t kSize>
+requires (kSize > 0)
+struct array
+{
+    T m_data[kSize];
+
+    [[nodiscard]] constexpr bool is_empty() const { return false; }
+
+    [[nodiscard]] constexpr isize_t size() const { return kSize; }
+
+    constexpr auto data(this auto&& self)
+    {
+        using return_type = copy_const_t<un_ref_t<decltype(self)>, T>*;
+        return static_cast<return_type>(self.m_data);
+    }
+
+    constexpr auto begin(this auto&& self)
+    {
+        return contiguous_iterator{self.data()};
+    }
+
+    constexpr auto end(this auto&& self)
+    {
+        return contiguous_iterator{self.data() + kSize};
+    }
+
+    template<isize_t kSpanSize>
+    requires (kSpanSize == kSize || kSpanSize == dynamic_size)
+    constexpr operator span<const T, kSpanSize>() const // NOLINT(*explicit*)
+    {
+        return as_span();
+    }
+
+    template<isize_t kSpanSize>
+    requires (kSpanSize == kSize || kSpanSize == dynamic_size)
+    constexpr operator span<T, kSpanSize>() // NOLINT(*explicit*)
+    {
+        return as_span();
+    }
+
+    constexpr auto as_span(this auto&& self)
+    {
+        using type = copy_const_t<un_ref_t<decltype(self)>, T>;
+        return span<type, kSize>{self.data(), self.size()};
+    }
+
+    constexpr auto&& operator[](this auto&& self, isize_t i)
+    {
+        ASL_ASSERT(i >= 0 && i <= self.size());
+        return std::forward_like<decltype(self)>(std::forward<decltype(self)>(self).data()[i]);
+    }
+};
+
+
+} // namespace asl
+
--- a/asl/types/array_tests.cpp
+++ b/asl/types/array_tests.cpp
@ -0,0 +1,122 @@
+// Copyright 2025 Steven Le Rouzic
+//
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include "asl/types/array.hpp"
+
+#include "asl/testing/testing.hpp"
+#include "asl/tests/types.hpp"
+
+static_assert(sizeof(asl::array<int32_t, 8>) == 32);
+
+static_assert(asl::default_constructible<asl::array<int, 6>>);
+static_assert(asl::trivially_default_constructible<asl::array<int, 6>>);
+
+static_assert(asl::default_constructible<asl::array<TrivialType, 6>>);
+static_assert(asl::trivially_default_constructible<asl::array<TrivialType, 6>>);
+static_assert(asl::trivially_copy_constructible<asl::array<TrivialType, 6>>);
+static_assert(asl::trivially_copy_assignable<asl::array<TrivialType, 6>>);
+static_assert(asl::trivially_move_constructible<asl::array<TrivialType, 6>>);
+static_assert(asl::trivially_move_assignable<asl::array<TrivialType, 6>>);
+
+static_assert(asl::default_constructible<asl::array<TrivialTypeDefaultValue, 6>>);
+static_assert(!asl::trivially_default_constructible<asl::array<TrivialTypeDefaultValue, 6>>);
+
+static_assert(asl::trivially_destructible<asl::array<int, 6>>);
+static_assert(asl::trivially_destructible<asl::array<TrivialType, 6>>);
+static_assert(!asl::trivially_destructible<asl::array<WithDestructor, 6>>);
+
+static_assert(asl::copyable<asl::array<Copyable, 6>>);
+static_assert(!asl::copyable<asl::array<MoveableOnly, 6>>);
+static_assert(!asl::copyable<asl::array<Pinned, 6>>);
+
+static_assert(asl::moveable<asl::array<Copyable, 6>>);
+static_assert(asl::moveable<asl::array<MoveableOnly, 6>>);
+static_assert(!asl::moveable<asl::array<Pinned, 6>>);
+
+ASL_TEST(construct_default)
+{
+    asl::array<int, 4> arr{};
+
+    ASL_TEST_EXPECT(static_cast<void*>(&arr) == static_cast<void*>(arr.data()));
+
+    ASL_TEST_EXPECT(arr[0] == 0);
+    ASL_TEST_EXPECT(arr[1] == 0);
+    ASL_TEST_EXPECT(arr[2] == 0);
+    ASL_TEST_EXPECT(arr[3] == 0);
+
+    ASL_TEST_EXPECT(arr.data()[0] == 0); // NOLINT
+    ASL_TEST_EXPECT(arr.data()[1] == 0); // NOLINT
+    ASL_TEST_EXPECT(arr.data()[2] == 0); // NOLINT
+    ASL_TEST_EXPECT(arr.data()[3] == 0); // NOLINT
+}
+
+ASL_TEST(construct)
+{
+    asl::array<int, 4> arr{10, 11, 12, 13};
+
+    ASL_TEST_EXPECT(arr[0] == 10);
+    ASL_TEST_EXPECT(arr[1] == 11);
+    ASL_TEST_EXPECT(arr[2] == 12);
+    ASL_TEST_EXPECT(arr[3] == 13);
+
+    ASL_TEST_EXPECT(arr.data()[0] == 10); // NOLINT
+    ASL_TEST_EXPECT(arr.data()[1] == 11); // NOLINT
+    ASL_TEST_EXPECT(arr.data()[2] == 12); // NOLINT
+    ASL_TEST_EXPECT(arr.data()[3] == 13); // NOLINT
+}
+
+static_assert(asl::convertible_to<asl::array<int, 4>, asl::span<int, 4>>);
+static_assert(asl::convertible_to<asl::array<int, 4>, asl::span<int>>);
+
+ASL_TEST(sized_span)
+{
+    asl::array<int, 4> arr{10, 11, 12, 13};
+    const asl::span<int, 4> s1 = arr;
+
+    ASL_TEST_EXPECT(s1.size() == 4);
+    ASL_TEST_EXPECT(s1.data() == arr.data());
+    ASL_TEST_EXPECT(s1[0] == 10);
+    ASL_TEST_EXPECT(s1[1] == 11);
+    ASL_TEST_EXPECT(s1[2] == 12);
+    ASL_TEST_EXPECT(s1[3] == 13);
+}
+
+ASL_TEST(unsized_span)
+{
+    asl::array<int, 4> arr{10, 11, 12, 13};
+    const asl::span<int> s2 = arr;
+
+    ASL_TEST_EXPECT(s2.size() == 4);
+    ASL_TEST_EXPECT(s2[0] == 10);
+    ASL_TEST_EXPECT(s2[1] == 11);
+    ASL_TEST_EXPECT(s2[2] == 12);
+    ASL_TEST_EXPECT(s2[3] == 13);
+}
+
+ASL_TEST(iterator)
+{
+    const asl::array<int, 4> arr{10, 11, 12, 13};
+
+    auto it = arr.begin();
+    auto end = arr.end();
+
+    ASL_TEST_ASSERT(it != end);
+    ASL_TEST_EXPECT(*it == 10);
+    it++;
+
+    ASL_TEST_ASSERT(it != end);
+    ASL_TEST_EXPECT(*it == 11);
+    it++;
+
+    ASL_TEST_ASSERT(it != end);
+    ASL_TEST_EXPECT(*it == 12);
+    it++;
+
+    ASL_TEST_ASSERT(it != end);
+    ASL_TEST_EXPECT(*it == 13);
+    it++;
+
+    ASL_TEST_ASSERT(it == end);
+}
+
--- a/asl/types/box.hpp
+++ b/asl/types/box.hpp
@ -29,21 +29,21 @@ public:

    constexpr box(T* ptr, Allocator alloc)
        : m_ptr{ptr}
-        , m_alloc{ASL_MOVE(alloc)}
+        , m_alloc{std::move(alloc)}
    {
        ASL_ASSERT(m_ptr != nullptr);
    }

    constexpr box(box&& other)
        : m_ptr{exchange(other.m_ptr, nullptr)}
-        , m_alloc{ASL_MOVE(other.m_alloc)}
+        , m_alloc{std::move(other.m_alloc)}
    {}

    template<is_object U>
-    requires convertible_from<T*, U*>
-    constexpr box(box<U, Allocator>&& other) // NOLINT(*-explicit-conversions)
+    requires convertible_to<U*, T*>
+    constexpr box(box<U, Allocator>&& other) // NOLINT(*explicit*,*-not-moved)
        : m_ptr{exchange(other.m_ptr, nullptr)}
-        , m_alloc{ASL_MOVE(other.m_alloc)}
+        , m_alloc{std::move(other.m_alloc)}
    {}

    constexpr box& operator=(box&& other)
@ -53,7 +53,7 @@ public:
        if (m_ptr != nullptr) { reset(); }

        m_ptr = exchange(other.m_ptr, nullptr);
-        m_alloc = ASL_MOVE(other.m_alloc);
+        m_alloc = std::move(other.m_alloc);

        return *this;
    }
@ -76,18 +76,21 @@ public:
        }
    }

-    constexpr T* get() const { return m_ptr; }
-
-    constexpr T& operator*() const
+    constexpr auto* get(this auto&& self)
    {
-        ASL_ASSERT(m_ptr != nullptr);
-        return *m_ptr;
+        return self.m_ptr;
    }

-    constexpr T* operator->() const
+    constexpr auto&& operator*(this auto&& self)
    {
-        ASL_ASSERT(m_ptr != nullptr);
-        return m_ptr;
+        ASL_ASSERT(self.m_ptr != nullptr);
+        return std::forward_like<decltype(self)&&>(*self.m_ptr);
+    }
+
+    constexpr auto* operator->(this auto&& self)
+    {
+        ASL_ASSERT(self.m_ptr != nullptr);
+        return self.m_ptr;
    }

    constexpr bool operator==(niche_t) const
@ -99,7 +102,7 @@ public:
    requires hashable<T>
    friend H AslHashValue(H h, const box& b)
    {
-        return H::combine(ASL_MOVE(h), *b);
+        return H::combine(std::move(h), *b);
    }

    template<is_object U, allocator A>
@ -114,8 +117,8 @@ constexpr box<T, Allocator> make_box_in(Allocator allocator, Args&&... args)
    requires constructible_from<T, Args&&...>
 {
    void* raw_ptr = allocator.alloc(layout::of<T>());
-    auto* ptr = construct_at<T>(raw_ptr, ASL_FWD(args)...);
-    return box(ptr, ASL_MOVE(allocator));
+    auto* ptr = construct_at<T>(raw_ptr, std::forward<Args>(args)...);
+    return box(ptr, std::move(allocator));
 }

 template<is_object T, allocator Allocator = DefaultAllocator, typename... Args>
@ -124,14 +127,14 @@ constexpr box<T, Allocator> make_box(Args&&... args)
 {
    Allocator allocator{};
    void* raw_ptr = allocator.alloc(layout::of<T>());
-    auto* ptr = construct_at<T>(raw_ptr, ASL_FWD(args)...);
-    return box<T>(ptr, ASL_MOVE(allocator));
+    auto* ptr = construct_at<T>(raw_ptr, std::forward<Args>(args)...);
+    return box<T>(ptr, std::move(allocator));
 }

 template<is_object T, allocator A>
 constexpr T* leak(box<T, A>&& b)
 {
-    return exchange(b.m_ptr, nullptr);
+    return exchange(std::move(b).m_ptr, nullptr);
 }

 } // namespace asl
--- a/asl/types/box_tests.cpp
+++ b/asl/types/box_tests.cpp
@ -23,7 +23,7 @@ ASL_TEST(destructor)
        ASL_TEST_ASSERT(!d);


-        auto box3 = ASL_MOVE(box);
+        auto box3 = std::move(box);
        ASL_TEST_ASSERT(!d);
    }

@ -35,7 +35,7 @@ ASL_TEST(value)
    auto b = asl::make_box<int>(24);
    ASL_TEST_EXPECT(*b == 24);

-    auto b2 = ASL_MOVE(b);
+    auto b2 = std::move(b);
    ASL_TEST_EXPECT(*b2 == 24);
 }

@ -44,7 +44,7 @@ ASL_TEST(ptr)
    auto b = asl::make_box<int>(24);
    auto* ptr1 = b.get();

-    auto b2 = ASL_MOVE(b);
+    auto b2 = std::move(b);
    auto* ptr2 = b2.get();
    ASL_TEST_EXPECT(ptr1 == ptr2);
 }
@ -81,7 +81,7 @@ ASL_TEST(niche)
    ASL_TEST_EXPECT(destroyed);
 }

-class Base
+class Base // NOLINT
 {
 public:
    virtual ~Base() = default;
@ -94,10 +94,10 @@ public:
    int number() override { return 2; }
 };

-static_assert(asl::convertible_from<asl::box<Base>, asl::box<Derived>>);
-static_assert(asl::convertible_from<asl::box<Base>, asl::box<Base>>);
-static_assert(!asl::convertible_from<asl::box<Derived>, asl::box<Base>>);
-static_assert(!asl::convertible_from<asl::box<int>, asl::box<float>>);
+static_assert(asl::convertible_to<asl::box<Derived>, asl::box<Base>>);
+static_assert(asl::convertible_to<asl::box<Base>, asl::box<Base>>);
+static_assert(!asl::convertible_to<asl::box<Base>, asl::box<Derived>>);
+static_assert(!asl::convertible_to<asl::box<float>, asl::box<int>>);

 ASL_TEST(derived)
 {
--- a/asl/types/function.hpp
+++ b/asl/types/function.hpp
@ -0,0 +1,288 @@
+// Copyright 2025 Steven Le Rouzic
+//
+// SPDX-License-Identifier: BSD-3-Clause
+
+#pragma once
+
+#include "asl/base/utility.hpp"
+#include "asl/base/meta.hpp"
+#include "asl/base/integers.hpp"
+#include "asl/memory/allocator.hpp"
+#include "asl/base/functional.hpp"
+
+namespace asl
+{
+
+namespace function_detail
+{
+
+static constexpr isize_t kStorageSize = size_of<void*> * 2;
+
+struct Storage
+{
+    alignas(align_of<void*>) byte raw[kStorageSize];
+
+    [[nodiscard]]
+    void* get_ptr() const
+    {
+        // NOLINTNEXTLINE(*-const-cast)
+        return const_cast<void*>(static_cast<const void*>(raw));
+    }
+};
+
+template<typename T>
+concept can_be_stored_inline =
+    size_of<T> <= size_of<Storage> &&
+    align_of<Storage> % align_of<T> == 0;
+
+enum class FunctionOp : uint8_t
+{
+    kDestroyThis,
+    kCopyFromOtherToThisUninit,
+    kMoveFromOtherToThisUninit,
+};
+
+template<typename Functor, bool kStoreInline = can_be_stored_inline<Functor>>
+struct FunctionImplBase
+{
+    using Allocator = DefaultAllocator;
+
+    template<typename T>
+    static void create(Storage* storage, T&& t)
+    {
+        Allocator allocator{};
+        auto* ptr = alloc_new<Functor>(allocator, std::forward<T>(t));
+        asl::memcpy(storage->get_ptr(), static_cast<void*>(&ptr), size_of<void*>);
+    }
+
+    static Functor** get_functor_ptr(const Storage* storage)
+    {
+        // NOLINTNEXTLINE(*-reinterpret-cast)
+        return std::launder(reinterpret_cast<Functor**>(storage->get_ptr()));
+    }
+
+    static Functor* get_functor(const Storage* storage)
+    {
+        return *get_functor_ptr(storage);
+    }
+
+    static void op(Storage* this_storage, Storage* other_storage, FunctionOp op)
+    {
+        switch (op)
+        {
+            using enum FunctionOp;
+            case kDestroyThis:
+            {
+                Allocator allocator{};
+                alloc_delete(allocator, get_functor(this_storage));
+                break;
+            }
+            case kCopyFromOtherToThisUninit:
+            {
+                create(this_storage, *static_cast<const Functor*>(get_functor(other_storage)));
+                break;
+            }
+            case kMoveFromOtherToThisUninit:
+            {
+                auto* ptr = asl::exchange(*get_functor_ptr(other_storage), nullptr);
+                asl::memcpy(this_storage->get_ptr(), static_cast<void*>(&ptr), size_of<void*>);
+                break;
+            }
+            default: break;
+        }
+    }
+};
+
+template<typename Functor>
+struct FunctionImplBase<Functor, true>
+{
+    template<typename T>
+    static void create(Storage* storage, T&& t)
+    {
+        new (storage->get_ptr()) Functor(std::forward<T>(t));
+    }
+
+    static Functor* get_functor(const Storage* storage)
+    {
+        // NOLINTNEXTLINE(*-reinterpret-cast)
+        return std::launder(reinterpret_cast<Functor*>(storage->get_ptr()));
+    }
+
+    static void op(Storage* this_storage, Storage* other_storage, FunctionOp op)
+    {
+        switch (op)
+        {
+            using enum FunctionOp;
+            case kDestroyThis:
+            {
+                destroy(get_functor(this_storage));
+                break;
+            }
+            case kCopyFromOtherToThisUninit:
+            {
+                create(this_storage, *static_cast<const Functor*>(get_functor(other_storage)));
+                break;
+            }
+            case kMoveFromOtherToThisUninit:
+            {
+                auto* other_functor = get_functor(other_storage);
+                create(this_storage, std::move(*static_cast<const Functor*>(other_functor)));
+                destroy(other_functor);
+                break;
+            }
+            default: break;
+        }
+    }
+};
+
+template<typename Functor, typename R, typename... Args>
+struct FunctionImpl : FunctionImplBase<Functor>
+{
+    static R invoke(Args... args, const Storage& storage)
+    {
+        auto* functor = FunctionImplBase<Functor>::get_functor(&storage);
+        return asl::invoke(*functor, std::forward<Args>(args)...);
+    }
+};
+
+
+template<typename T, typename R, typename... Args>
+concept valid_functor =
+    copy_constructible<T>
+    && move_constructible<T>
+    && invocable<T, Args...>
+    && same_as<R, invoke_result_t<T, Args...>>;
+
+}  // namespace function_detail
+
+template<typename T>
+class function;
+
+template<typename R, typename... Args>
+class function<R(Args...)> // NOLINT(*-member-init)
+{
+    using InvokeFn = R (*)(Args..., const function_detail::Storage&);
+    using OpFn = void (*)(function_detail::Storage*, function_detail::Storage*, function_detail::FunctionOp);
+
+    function_detail::Storage m_storage;
+    InvokeFn                 m_invoke{};
+    OpFn                     m_op{};
+
+    void destroy()
+    {
+        if (m_op != nullptr)
+        {
+            (*m_op)(&m_storage, nullptr, function_detail::FunctionOp::kDestroyThis);
+        }
+    }
+
+public:
+    function() = default;
+
+    template<typename T>
+    function(T&& func) // NOLINT(*explicit*,*-member-init)
+        requires (
+            !same_as<function, un_cvref_t<T>>
+            && function_detail::valid_functor<T, R, Args...>
+        )
+    {
+        using Functor = decay_t<T>;
+        using Impl = function_detail::FunctionImpl<Functor, R, Args...>;
+
+        Impl::create(&m_storage, std::forward<T>(func));
+        m_invoke = &Impl::invoke; // NOLINT(*-member-initializer)
+        m_op = &Impl::op; // NOLINT(*-member-initializer)
+    }
+
+    function(const function& other) // NOLINT(*-member-init)
+        : m_invoke{other.m_invoke}
+        , m_op{other.m_op}
+    {
+        if (m_op != nullptr)
+        {
+            m_op(
+                &m_storage,
+                const_cast<function_detail::Storage*>(&other.m_storage), // NOLINT(*-const-cast)
+                function_detail::FunctionOp::kCopyFromOtherToThisUninit);
+        }
+    }
+
+    function(function&& other) // NOLINT(*-member-init)
+        : m_invoke{asl::exchange(other.m_invoke, nullptr)}
+        , m_op{asl::exchange(other.m_op, nullptr)}
+    {
+        if (m_op != nullptr)
+        {
+            m_op(
+                &m_storage,
+                &other.m_storage,
+                function_detail::FunctionOp::kMoveFromOtherToThisUninit);
+        }
+    }
+
+    ~function()
+    {
+        destroy();
+    }
+
+    function& operator=(const function& other)
+    {
+        if (this != &other)
+        {
+            destroy();
+
+            m_invoke = other.m_invoke;
+            m_op = other.m_op;
+
+            m_op(
+                &m_storage,
+                const_cast<function_detail::Storage*>(&other.m_storage), // NOLINT(*-const-cast)
+                function_detail::FunctionOp::kCopyFromOtherToThisUninit);
+        }
+        return *this;
+    }
+
+    function& operator=(function&& other)
+    {
+        if (this != &other)
+        {
+            destroy();
+
+            m_invoke = asl::exchange(other.m_invoke, nullptr);
+            m_op = asl::exchange(other.m_op, nullptr);
+
+            m_op(
+                &m_storage,
+                &other.m_storage,
+                function_detail::FunctionOp::kMoveFromOtherToThisUninit);
+        }
+        return *this;
+    }
+
+    template<typename T>
+    function& operator=(T&& func)
+        requires (
+            !same_as<function, un_cvref_t<T>>
+            && function_detail::valid_functor<T, R, Args...>
+        )
+    {
+        destroy();
+
+        using Functor = decay_t<T>;
+        using Impl = function_detail::FunctionImpl<Functor, R, Args...>;
+
+        Impl::create(&m_storage, std::forward<T>(func));
+        m_invoke = &Impl::invoke;
+        m_op = &Impl::op;
+
+        return *this;
+    }
+
+    constexpr R operator()(Args... args) const
+    {
+        ASL_ASSERT(m_invoke);
+        return m_invoke(args..., m_storage);
+    }
+};
+
+} // namespace asl
--- a/asl/types/function_ref.hpp
+++ b/asl/types/function_ref.hpp
@ -0,0 +1,72 @@
+// Copyright 2025 Steven Le Rouzic
+//
+// SPDX-License-Identifier: BSD-3-Clause
+
+#pragma once
+
+#include "asl/base/utility.hpp"
+#include "asl/base/meta.hpp"
+#include "asl/base/functional.hpp"
+#include "asl/memory/memory.hpp"
+
+namespace asl
+{
+
+template<typename T>
+class function_ref;
+
+template<typename R, typename... Args>
+class function_ref<R(Args...)>
+{
+    using InvokeFn = R (*)(Args..., void*);
+
+    void*       m_obj;
+    InvokeFn    m_invoke;
+
+    template<typename T>
+    static R invoke(Args... args, void* obj)
+    {
+        // NOLINTNEXTLINE(*-reinterpret-cast)
+        return asl::invoke(*reinterpret_cast<T*>(obj), std::forward<Args>(args)...);
+    }
+
+public:
+    function_ref() = delete;
+
+    ASL_DEFAULT_COPY_MOVE(function_ref);
+    ~function_ref() = default;
+
+    template<typename T>
+    function_ref(T&& t) // NOLINT(*-missing-std-forward, *explicit*)
+        requires (
+            !same_as<un_cvref_t<T>, function_ref>
+            && invocable<T, Args...>
+            && same_as<invoke_result_t<T, Args...>, R>
+        )
+        // NOLINTNEXTLINE(*cast*)
+        : m_obj{const_cast<void*>(reinterpret_cast<const void*>(address_of(t)))}
+        , m_invoke{invoke<un_ref_t<T>>}
+    {}
+
+    template<typename T>
+    function_ref& operator=(T&& t) // NOLINT(*-missing-std-forward)
+        requires (
+            !same_as<un_cvref_t<T>, function_ref>
+            && invocable<T, Args...>
+            && same_as<invoke_result_t<T, Args...>, R>
+        )
+    {
+        // NOLINTNEXTLINE(*cast*)
+        m_obj = const_cast<void*>(reinterpret_cast<const void*>(address_of(t)));
+        m_invoke = invoke<un_ref_t<T>>;
+
+        return *this;
+    }
+
+    constexpr R operator()(this function_ref self, Args... args)
+    {
+        return self.m_invoke(std::forward<Args>(args)..., self.m_obj);
+    }
+};
+
+} // namespace asl
--- a/asl/types/function_ref_tests.cpp
+++ b/asl/types/function_ref_tests.cpp
@ -0,0 +1,54 @@
+// Copyright 2025 Steven Le Rouzic
+//
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include "asl/testing/testing.hpp"
+#include "asl/types/function_ref.hpp"
+
+static int add(int a, int b)
+{
+    return a + b;
+}
+
+struct Functor
+{
+    int state = 0;
+
+    int operator()(int x, int)
+    {
+        state += x;
+        return state;
+    }
+};
+
+static int invoke_fn_ref(asl::function_ref<int(int, int)> fn, int a, int b)
+{
+    return fn(a, b);
+}
+
+ASL_TEST(function_ref)
+{
+    const asl::function_ref<int(int, int)> fn(add);
+    ASL_TEST_EXPECT(invoke_fn_ref(fn, 4, 5) == 9);
+
+    ASL_TEST_EXPECT(invoke_fn_ref(add, 4, 5) == 9);
+
+    ASL_TEST_EXPECT(invoke_fn_ref([](int a, int b) { return a * b; }, 4, 5) == 20);
+
+    Functor fun;
+    ASL_TEST_EXPECT(invoke_fn_ref(fun, 4, 5) == 4);
+    ASL_TEST_EXPECT(invoke_fn_ref(fun, 4, 5) == 8);
+    ASL_TEST_EXPECT(invoke_fn_ref(fun, 4, 5) == 12);
+
+    asl::function_ref<int(int, int)> fn2 = fn;
+    ASL_TEST_EXPECT(invoke_fn_ref(fn2, 4, 5) == 9);
+
+    fn2 = [](int a, int b) { return a - b; };
+    ASL_TEST_EXPECT(invoke_fn_ref(fn2, 4, 5) == -1);
+
+    fn2 = fn;
+    ASL_TEST_EXPECT(invoke_fn_ref(fn2, 4, 5) == 9);
+
+    fn2 = add;
+    ASL_TEST_EXPECT(invoke_fn_ref(fn2, 4, 5) == 9);
+}
--- a/asl/types/function_tests.cpp
+++ b/asl/types/function_tests.cpp
@ -0,0 +1,195 @@
+// Copyright 2025 Steven Le Rouzic
+//
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include "asl/testing/testing.hpp"
+#include "asl/types/function.hpp"
+
+static_assert(asl::function_detail::can_be_stored_inline<int(*)(int, int, int)>);
+static_assert(asl::function_detail::can_be_stored_inline<decltype([](){})>);
+static_assert(asl::function_detail::can_be_stored_inline<decltype([]() static {})>);
+static_assert(asl::function_detail::can_be_stored_inline<decltype([a = 1ULL, b = 2ULL](){ return a + b; })>); // NOLINT
+static_assert(asl::function_detail::can_be_stored_inline<decltype([a = 1ULL, b = 2ULL]() mutable { return a = b++; })>); // NOLINT
+static_assert(!asl::function_detail::can_be_stored_inline<decltype([a = 1ULL, b = 2ULL, c = 3ULL](){ return a + b + c; })>); // NOLINT
+
+static int add(int x, int y)
+{
+    return x + y;
+}
+
+ASL_TEST(function_pointer)
+{
+    const asl::function<int(int, int)> fn = add;
+    ASL_TEST_EXPECT(fn(4, 5) == 9);
+    ASL_TEST_EXPECT(fn(40, 50) == 90);
+}
+
+ASL_TEST(lambda)
+{
+    const asl::function<int(int, int)> fn = [](int a, int b) {
+        return a + b;
+    };
+    ASL_TEST_EXPECT(fn(4, 5) == 9);
+}
+
+ASL_TEST(lambda_static)
+{
+    const asl::function<int(int, int)> fn = [](int a, int b) static {
+        return a + b;
+    };
+    ASL_TEST_EXPECT(fn(4, 5) == 9);
+}
+
+ASL_TEST(lambda_static_state)
+{
+    const asl::function<int(int)> fn = [state = 0](int b) mutable {
+        state += b;
+        return state;
+    };
+
+    ASL_TEST_EXPECT(fn(1) == 1);
+    ASL_TEST_EXPECT(fn(2) == 3);
+    ASL_TEST_EXPECT(fn(3) == 6);
+    ASL_TEST_EXPECT(fn(4) == 10);
+}
+
+ASL_TEST(lambda_state)
+{
+    int state = 0;
+    const asl::function<void(int)> fn = [&state](int x) {
+        state += x;
+    };
+
+    ASL_TEST_EXPECT(state == 0);
+
+    fn(5);
+    ASL_TEST_EXPECT(state == 5);
+
+    fn(4);
+    ASL_TEST_EXPECT(state == 9);
+}
+
+ASL_TEST(lambda_big_state)
+{
+    int s0 = 0;
+    int s1 = 0;
+    int s2 = 0;
+    int s3 = 0;
+
+    const asl::function<void(int)> fn = [&](int x) {
+        s0 += x;
+        s1 += x + 1;
+        s2 += x + 2;
+        s3 += x + 3;
+    };
+
+    ASL_TEST_EXPECT(s0 == 0);
+    ASL_TEST_EXPECT(s1 == 0);
+    ASL_TEST_EXPECT(s2 == 0);
+    ASL_TEST_EXPECT(s3 == 0);
+
+    fn(5);
+    ASL_TEST_EXPECT(s0 == 5);
+    ASL_TEST_EXPECT(s1 == 6);
+    ASL_TEST_EXPECT(s2 == 7);
+    ASL_TEST_EXPECT(s3 == 8);
+
+    fn(4);
+    ASL_TEST_EXPECT(s0 == 9);
+    ASL_TEST_EXPECT(s1 == 11);
+    ASL_TEST_EXPECT(s2 == 13);
+    ASL_TEST_EXPECT(s3 == 15);
+}
+
+struct Functor
+{
+    int state{};
+
+    int operator()(int x)
+    {
+        state += x;
+        return state;
+    }
+};
+
+ASL_TEST(functor)
+{
+    const asl::function<int(int)> fn = Functor{};
+
+    ASL_TEST_EXPECT(fn(1) == 1);
+    ASL_TEST_EXPECT(fn(2) == 3);
+    ASL_TEST_EXPECT(fn(3) == 6);
+    ASL_TEST_EXPECT(fn(4) == 10);
+}
+
+ASL_TEST(copy_move_construct_small)
+{
+    asl::function<int(int, int)> fn = [x = 0](int a, int b) mutable { return x++ + a + b; };
+    ASL_TEST_EXPECT(fn(1, 3) == 4);
+
+    asl::function<int(int, int)> fn2 = fn;
+    ASL_TEST_EXPECT(fn(1, 3) == 5);
+    ASL_TEST_EXPECT(fn2(5, 3) == 9);
+
+    asl::function<int(int, int)> fn3 = std::move(fn2);
+    ASL_TEST_EXPECT(fn(1, 3) == 6);
+    ASL_TEST_EXPECT(fn3(5, 3) == 10);
+
+    fn2 = fn;
+    ASL_TEST_EXPECT(fn(1, 3) == 7);
+    ASL_TEST_EXPECT(fn2(5, 3) == 11);
+    ASL_TEST_EXPECT(fn3(5, 3) == 11);
+
+    fn3 = std::move(fn);
+    ASL_TEST_EXPECT(fn2(5, 3) == 12);
+    ASL_TEST_EXPECT(fn3(5, 3) == 12);
+}
+
+ASL_TEST(copy_move_construct_big)
+{
+    const int64_t v1 = 1;
+    const int64_t v2 = 2;
+    const int64_t v3 = 3;
+    const int64_t v4 = 4;
+
+    asl::function<int64_t(int)> fn = [=](int x) { return v1 + v2 + v3 + v4 + x; };
+    ASL_TEST_EXPECT(fn(1) == 11);
+
+    asl::function<int64_t(int)> fn2 = fn;
+    ASL_TEST_EXPECT(fn(3) == 13);
+    ASL_TEST_EXPECT(fn2(5) == 15);
+
+    asl::function<int64_t(int)> fn3 = std::move(fn2);
+    ASL_TEST_EXPECT(fn(1) == 11);
+    ASL_TEST_EXPECT(fn3(3) == 13);
+
+    fn2 = fn;
+    ASL_TEST_EXPECT(fn(1) == 11);
+    ASL_TEST_EXPECT(fn2(5) == 15);
+    ASL_TEST_EXPECT(fn3(3) == 13);
+
+    fn3 = std::move(fn);
+    ASL_TEST_EXPECT(fn2(5) == 15);
+    ASL_TEST_EXPECT(fn3(3) == 13);
+}
+
+ASL_TEST(replace)
+{
+    asl::function<int(int)> fn = [](int x) { return x + 1; };
+    ASL_TEST_EXPECT(fn(5) == 6);
+
+    fn = [](int x) { return x + 3; };
+    ASL_TEST_EXPECT(fn(5) == 8);
+}
+
+static int foo(const asl::function<int(int, int)>& fn)
+{
+    return fn(5, 5);
+}
+
+ASL_TEST(function_parameter)
+{
+    ASL_TEST_EXPECT(foo(add) == 10);
+    ASL_TEST_EXPECT(foo([](int a, int b) { return a + b; }) == 10);
+}
+
--- a/asl/types/maybe_uninit.hpp
+++ b/asl/types/maybe_uninit.hpp
@ -23,7 +23,7 @@ public:

    explicit constexpr maybe_uninit(in_place_t, auto&&... args)
        requires constructible_from<T, decltype(args)...>
-        : m_value{ASL_FWD(args)...}
+        : m_value{std::forward<decltype(args)>(args)...}
    {}

    constexpr maybe_uninit(const maybe_uninit&) requires trivially_copy_constructible<T> = default;
@ -33,10 +33,10 @@ public:
    constexpr maybe_uninit(maybe_uninit&&) requires (!trivially_move_constructible<T>) {} // NOLINT

    constexpr maybe_uninit& operator=(const maybe_uninit&) requires trivially_copy_assignable<T> = default;
-    constexpr maybe_uninit& operator=(const maybe_uninit&) requires (!trivially_copy_assignable<T>) {}
+    constexpr maybe_uninit& operator=(const maybe_uninit&) requires (!trivially_copy_assignable<T>) { return *this; } // NOLINT

    constexpr maybe_uninit& operator=(maybe_uninit&&) requires trivially_move_assignable<T> = default;
-    constexpr maybe_uninit& operator=(maybe_uninit&&) requires (!trivially_move_assignable<T>) {}
+    constexpr maybe_uninit& operator=(maybe_uninit&&) requires (!trivially_move_assignable<T>) { return *this; } // NOLINT

    constexpr ~maybe_uninit() requires trivially_destructible<T> = default;
    constexpr ~maybe_uninit() requires (!trivially_destructible<T>) {} // NOLINT
@ -45,14 +45,14 @@ public:
    constexpr void construct_unsafe(auto&&... args)
        requires constructible_from<T, decltype(args)...>
    {
-        construct_at<T>(&m_value, ASL_FWD(args)...);
+        construct_at<T>(&m_value, std::forward<decltype(args)>(args)...);
    }

    // @Safety Value must have been initialized
    constexpr void assign_unsafe(auto&& value)
        requires assignable_from<T&, decltype(value)>
    {
-        m_value = ASL_FWD(value);
+        m_value = std::forward<decltype(value)>(value);
    }

    // @Safety Value must have been initialized
@ -67,7 +67,7 @@ public:
    // @Safety Value must have been initialized
    constexpr auto&& as_init_unsafe(this auto&& self)
    {
-        return ASL_FWD(self).m_value;
+        return std::forward<decltype(self)>(self).m_value;
    }
 };

--- a/asl/types/maybe_uninit_tests.cpp
+++ b/asl/types/maybe_uninit_tests.cpp
@ -10,6 +10,8 @@ static_assert(asl::size_of<int> == asl::size_of<asl::maybe_uninit<int>>);
 static_assert(asl::align_of<int> == asl::align_of<asl::maybe_uninit<int>>);

 #define TEST_TYPE_PROPERTIES(PRP) \
+    static_assert(asl::PRP<asl::maybe_uninit<int>> == asl::PRP<int>); \
+    static_assert(asl::PRP<asl::maybe_uninit<void*>> == asl::PRP<void*>); \
    static_assert(asl::PRP<asl::maybe_uninit<TrivialType>> == asl::PRP<TrivialType>); \
    static_assert(asl::PRP<asl::maybe_uninit<TrivialTypeDefaultValue>> == asl::PRP<TrivialTypeDefaultValue>); \
    static_assert(asl::PRP<asl::maybe_uninit<WithDestructor>> == asl::PRP<WithDestructor>); \
@ -17,6 +19,8 @@ static_assert(asl::align_of<int> == asl::align_of<asl::maybe_uninit<int>>);
    static_assert(asl::PRP<asl::maybe_uninit<MoveableOnly>> == asl::PRP<MoveableOnly>); \
    static_assert(asl::PRP<asl::maybe_uninit<Pinned>> == asl::PRP<Pinned>);

+// @Todo(C++26) We expect this to break once trivial unions land.
+// https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2025/p3074r7.html#just-make-it-work
 TEST_TYPE_PROPERTIES(trivially_default_constructible);
 TEST_TYPE_PROPERTIES(trivially_copy_constructible);
 TEST_TYPE_PROPERTIES(trivially_move_constructible);
--- a/asl/types/option.hpp
+++ b/asl/types/option.hpp
@ -74,19 +74,19 @@ class option

        if constexpr (!kHasNiche)
        {
-            m_payload.construct_unsafe(ASL_FWD(args)...);
+            m_payload.construct_unsafe(std::forward<Args>(args)...);
            m_has_value = true;
        }
        else
        {
            if constexpr (move_assignable<T>)
            {
-                m_payload.assign_unsafe(ASL_MOVE(T{ASL_FWD(args)...}));
+                m_payload.assign_unsafe(T{std::forward<Args>(args)...});
            }
            else
            {
                m_payload.destroy_unsafe();
-                m_payload.construct_unsafe(ASL_FWD(args)...);
+                m_payload.construct_unsafe(std::forward<Args>(args)...);
            }
        }
    }
@ -95,7 +95,7 @@ class option
    constexpr void assign(U&& arg)
    {
        ASL_ASSERT(has_value());
-        m_payload.assign_unsafe(ASL_FWD(arg));
+        m_payload.assign_unsafe(std::forward<U>(arg));
    }

 public:
@ -103,32 +103,32 @@ public:

    constexpr option() : option{nullopt} {}

-     // NOLINTNEXTLINE(*-explicit-conversions)
+     // NOLINTNEXTLINE(*explicit*)
    constexpr option(nullopt_t) requires (!kHasNiche) {}

-     // NOLINTNEXTLINE(*-explicit-conversions)
+     // NOLINTNEXTLINE(*explicit*)
    constexpr option(nullopt_t) requires kHasNiche : m_payload{in_place, niche_t{}} {}

    template<typename U = T>
-    constexpr explicit (!convertible_from<T, U&&>)
+    constexpr explicit (!convertible_to<U&&, T>)
    option(U&& value)
        requires (
            kHasNiche &&
            constructible_from<T, U&&> &&
            !same_as<un_cvref_t<U>, option>
        )
-        : m_payload{in_place, ASL_FWD(value)}
+        : m_payload{in_place, std::forward<U>(value)}
    {}

    template<typename U = T>
-    constexpr explicit (!convertible_from<T, U&&>)
+    constexpr explicit (!convertible_to<U&&, T>)
    option(U&& value)
        requires (
            !kHasNiche &&
            constructible_from<T, U&&> &&
            !is_option<U>
        )
-        : m_payload{in_place, ASL_FWD(value)}
+        : m_payload{in_place, std::forward<U>(value)}
        , m_has_value{true}
    {}

@ -154,12 +154,12 @@ public:
    {
        if (other.has_value())
        {
-            construct(ASL_MOVE(other.m_payload.as_init_unsafe()));
+            construct(std::move(other.m_payload.as_init_unsafe()));
        }
    }

    template<typename U>
-    constexpr explicit (!convertible_from<T, const U&>)
+    constexpr explicit (!convertible_to<const U&, T>)
    option(const option<U>& other)
        requires (
            constructible_from<T, const U&> &&
@ -174,7 +174,7 @@ public:
    }

    template<typename U>
-    constexpr explicit (!convertible_from<T, U&&>)
+    constexpr explicit (!convertible_to<U&&, T>)
    option(option<U>&& other)
        requires (
            constructible_from<T, U&&> &&
@ -184,7 +184,7 @@ public:
    {
        if (other.has_value())
        {
-            construct(ASL_MOVE(other.m_payload.as_init_unsafe()));
+            construct(std::move(other).m_payload.as_init_unsafe());
        }
    }

@ -204,11 +204,11 @@ public:
    {
        if (has_value())
        {
-            assign(ASL_FWD(value));
+            assign(std::forward<U>(value));
        }
        else
        {
-            construct(ASL_FWD(value));
+            construct(std::forward<U>(value));
        }

        return *this;
@ -259,11 +259,11 @@ public:
        {
            if (has_value())
            {
-                assign(ASL_MOVE(other.m_payload.as_init_unsafe()));
+                assign(std::move(other.m_payload.as_init_unsafe()));
            }
            else
            {
-                construct(ASL_MOVE(other.m_payload.as_init_unsafe()));
+                construct(std::move(other.m_payload.as_init_unsafe()));
            }
        }
        else if (has_value())
@ -313,11 +313,11 @@ public:
        {
            if (has_value())
            {
-                assign(ASL_MOVE(other.m_payload.as_init_unsafe()));
+                assign(std::move(other).m_payload.as_init_unsafe());
            }
            else
            {
-                construct(ASL_MOVE(other.m_payload.as_init_unsafe()));
+                construct(std::move(other).m_payload.as_init_unsafe());
            }
        }
        else if (has_value())
@ -342,7 +342,7 @@ public:
        {
            if constexpr (move_assignable<T>)
            {
-                m_payload.assign_unsafe(ASL_MOVE(T{niche_t{}}));
+                m_payload.assign_unsafe(std::move(T{niche_t{}}));
            }
            else
            {
@ -357,7 +357,7 @@ public:
        }
    }

-    constexpr bool has_value() const
+    [[nodiscard]] constexpr bool has_value() const
    {
        if constexpr (kHasNiche)
        {
@ -372,28 +372,28 @@ public:
    constexpr auto&& value(this auto&& self)
    {
        ASL_ASSERT_RELEASE(self.has_value());
-        return ASL_FWD(self).m_payload.as_init_unsafe();
+        return std::forward<decltype(self)>(self).m_payload.as_init_unsafe();
    }

    template<typename U>
    constexpr T value_or(U&& other_value) const&
-        requires copy_constructible<T> && convertible_from<T, U&&>
+        requires copy_constructible<T> && convertible_to<U&&, T>
    {
-        return has_value() ? value() : static_cast<T>(ASL_FWD(other_value));
+        return has_value() ? value() : static_cast<T>(std::forward<U>(other_value));
    }

    template<typename U>
    constexpr T value_or(U&& other_value) &&
-        requires move_constructible<T> && convertible_from<T, U&&>
+        requires move_constructible<T> && convertible_to<U&&, T>
    {
-        return has_value() ? ASL_MOVE(value()) : static_cast<T>(ASL_FWD(other_value));
+        return has_value() ? std::move(value()) : static_cast<T>(std::forward<U>(other_value));
    }

    constexpr T& emplace(auto&&... args) &
        requires constructible_from<T, decltype(args)...>
    {
        if (has_value()) { reset(); }
-        construct(ASL_FWD(args)...);
+        construct(std::forward<decltype(args)>(args)...);
        return value();
    }

@ -405,7 +405,7 @@ public:

        if (self.has_value())
        {
-            return invoke(ASL_FWD(f), ASL_FWD(self).value());
+            return invoke(std::forward<F>(f), std::forward<decltype(self)>(self).value());
        }
        return Result{ asl::nullopt };
    }
@ -417,7 +417,7 @@ public:
        if (self.has_value())
        {
            return option<un_cvref_t<Result>>{
-                invoke(ASL_FWD(f), ASL_FWD(self).value())
+                invoke(std::forward<F>(f), std::forward<decltype(self)>(self).value())
            };
        }
        return option<un_cvref_t<Result>>{ asl::nullopt };
@ -427,14 +427,14 @@ public:
    constexpr option or_else(F&& f) const&
        requires same_as<un_cvref_t<invoke_result_t<F>>, option>
    {
-        return has_value() ? *this : invoke(ASL_FWD(f));
+        return has_value() ? *this : invoke(std::forward<F>(f));
    }

    template<typename F>
    constexpr option or_else(F&& f) &&
        requires same_as<un_cvref_t<invoke_result_t<F>>, option>
    {
-        return has_value() ? ASL_MOVE(*this) : invoke(ASL_FWD(f));
+        return has_value() ? std::move(*this) : invoke(std::forward<F>(f));
    }

    template<typename H>
@ -443,9 +443,9 @@ public:
    {
        if (!opt.has_value())
        {
-            return H::combine(ASL_MOVE(h), 0);
+            return H::combine(std::move(h), 0);
        }
-        return H::combine(ASL_MOVE(h), 1, opt.value());
+        return H::combine(std::move(h), 1, opt.value());
    }
 };

--- a/asl/types/option_tests.cpp
+++ b/asl/types/option_tests.cpp
@ -62,20 +62,20 @@ static_assert(!asl::move_assignable<asl::option<Pinned>>);
 static_assert(asl::assignable_from<asl::option<Base*>&, asl::option<Derived*>>);
 static_assert(!asl::assignable_from<asl::option<Derived*>&, asl::option<Base*>>);

-static_assert(asl::convertible_from<asl::option<Base*>, asl::option<Derived*>>);
-static_assert(!asl::convertible_from<asl::option<Derived*>, asl::option<Base*>>);
+static_assert(asl::convertible_to<asl::option<Derived*>, asl::option<Base*>>);
+static_assert(!asl::convertible_to<asl::option<Base*>, asl::option<Derived*>>);

 class ExplicitConversion { public: explicit ExplicitConversion(int) {} };
 class ImplicitConversion { public: ImplicitConversion(int) {} }; // NOLINT

-static_assert(!asl::convertible_from<ExplicitConversion, int>);
-static_assert(asl::convertible_from<ImplicitConversion, int>);
+static_assert(!asl::convertible_to<int, ExplicitConversion>);
+static_assert(asl::convertible_to<int, ImplicitConversion>);

-static_assert(!asl::convertible_from<asl::option<ExplicitConversion>, int>);
-static_assert(asl::convertible_from<asl::option<ImplicitConversion>, int>);
+static_assert(!asl::convertible_to<int, asl::option<ExplicitConversion>>);
+static_assert(asl::convertible_to<int, asl::option<ImplicitConversion>>);

-static_assert(!asl::convertible_from<asl::option<ExplicitConversion>, asl::option<int>>);
-static_assert(asl::convertible_from<asl::option<ImplicitConversion>, asl::option<int>>);
+static_assert(!asl::convertible_to<asl::option<int>, asl::option<ExplicitConversion>>);
+static_assert(asl::convertible_to<asl::option<int>, asl::option<ImplicitConversion>>);

 static_assert(asl::trivially_copy_constructible<asl::option<int>>);
 static_assert(asl::trivially_copy_constructible<asl::option<TrivialType>>);
@ -99,8 +99,8 @@ static_assert(!asl::trivially_move_assignable<asl::option<MoveableOnly>>);

 ASL_TEST(make_null)
 {
-    asl::option<int> a;
-    asl::option<int> b = asl::nullopt;
+    const asl::option<int> a;
+    const asl::option<int> b = asl::nullopt;

    ASL_TEST_EXPECT(!a.has_value());
    ASL_TEST_EXPECT(!b.has_value());
@ -108,7 +108,7 @@ ASL_TEST(make_null)

 ASL_TEST(make_value)
 {
-    asl::option<int> a = 48;
+    const asl::option<int> a = 48;

    ASL_TEST_EXPECT(a.has_value());
 }
@ -129,10 +129,10 @@ ASL_TEST(call_destructor)
    {
        DestructorObserver obs(&destroyed);

-        asl::option<DestructorObserver> opt(ASL_MOVE(obs));
+        asl::option<DestructorObserver> opt(std::move(obs));
        ASL_TEST_EXPECT(!destroyed);

-        asl::option<DestructorObserver> opt2 = ASL_MOVE(opt);
+        const asl::option<DestructorObserver> opt2 = std::move(opt);
        ASL_TEST_EXPECT(!destroyed);
    }

@ -172,7 +172,7 @@ ASL_TEST(value_move)
    ASL_TEST_EXPECT(!destroyed);

    {
-        auto x = ASL_MOVE(opt).value();
+        auto x = std::move(opt).value();
        ASL_TEST_EXPECT(!destroyed);
    }

@ -208,27 +208,27 @@ ASL_TEST(convert_copy)
 ASL_TEST(convert_move)
 {
    asl::option<uint8_t> opt8 = uint8_t{8};
-    asl::option<uint16_t> opt16 = ASL_MOVE(opt8);
+    asl::option<uint16_t> opt16 = std::move(opt8);

    ASL_TEST_ASSERT(opt16.has_value());
    ASL_TEST_EXPECT(opt16.value() == 8);

-    opt8 = ASL_MOVE(uint8_t{10});
+    opt8 = uint8_t{10};
    ASL_TEST_ASSERT(opt8.has_value());
    ASL_TEST_EXPECT(opt8.value() == 10);

    opt16 = asl::nullopt;
    ASL_TEST_EXPECT(!opt16.has_value());

-    opt16 = ASL_MOVE(opt8);
+    opt16 = std::move(opt8);
    ASL_TEST_ASSERT(opt16.has_value());
    ASL_TEST_EXPECT(opt16.value() == 10);
 }

 ASL_TEST(value_or)
 {
-    asl::option<int> a = asl::nullopt;
-    asl::option<int> b = 2;
+    const asl::option<int> a = asl::nullopt;
+    const asl::option<int> b = 2;

    ASL_TEST_EXPECT(a.value_or(5) == 5);
    ASL_TEST_EXPECT(b.value_or(5) == 2);
@ -296,8 +296,8 @@ ASL_TEST(transform)

 ASL_TEST(or_else)
 {
-    asl::option<int> a = 5;
-    asl::option<int> b;
+    const asl::option<int> a = 5;
+    const asl::option<int> b;

    auto fn = []() -> asl::option<int> { return 12; };

--- a/asl/types/span.hpp
+++ b/asl/types/span.hpp
@ -14,6 +14,7 @@ namespace asl

 static constexpr isize_t dynamic_size = -1;

+// NOLINTBEGIN(*-convert-member-functions-to-static)
 template<typename T>
 class contiguous_iterator
 {
@ -22,7 +23,7 @@ class contiguous_iterator
 public:
    constexpr explicit contiguous_iterator(T* ptr) : m_ptr{ptr} {}

-    constexpr bool operator==(const contiguous_iterator& other) const = default;
+    constexpr bool operator==(this contiguous_iterator self, contiguous_iterator other) = default;

    constexpr contiguous_iterator& operator++()
    {
@ -35,9 +36,9 @@ public:
        return contiguous_iterator{ exchange(m_ptr, m_ptr + 1) };
    }

-    constexpr T& operator*() const { return *m_ptr; }
+    constexpr T& operator*(this contiguous_iterator self) { return *self.m_ptr; }

-    constexpr T* operator->() const { return m_ptr; }
+    constexpr T* operator->(this contiguous_iterator self) { return self.m_ptr; }
 };

 template<typename T>
@ -67,7 +68,7 @@ public:
        , m_size{size}
    {}

-    constexpr explicit span(T* data, isize_t size)
+    constexpr explicit span(T* data, [[maybe_unused]] isize_t size)
        requires (!kIsDynamic)
        : m_data{data}
    {
@ -75,27 +76,27 @@ public:
    }

    template<isize_t N>
-    constexpr span(T (&array)[N]) // NOLINT(*-explicit-conversions)
+    constexpr span(T (&array)[N]) // NOLINT(*explicit*)
        requires (kIsDynamic)
-        : m_data{array}
+        : m_data{static_cast<T*>(array)}
        , m_size{N}
    {}

    template<isize_t N>
-    constexpr span(T (&array)[N]) // NOLINT(*-explicit-conversions)
+    constexpr span(T (&array)[N]) // NOLINT(*explicit*)
        requires (!kIsDynamic) && (N == kSize)
-        : m_data{array}
+        : m_data{static_cast<T*>(array)}
    {}

    template<is_object U, isize_t kOtherSize>
    constexpr explicit(!kIsDynamic)
-    span(const span<U, kOtherSize>& other) // NOLINT(*-explicit-conversions)
+    span(const span<U, kOtherSize>& other)
        requires (
            (
                kIsDynamic ||
                is_dynamic(kOtherSize) ||
                kOtherSize == kSize
-            ) && convertible_from<T(&)[], U(&)[]>
+            ) && convertible_to<U(&)[], T(&)[]>
        )
        : span{static_cast<U*>(other.data()), other.size()}
    {
@ -109,115 +110,116 @@ public:

    ~span() = default;

-    constexpr isize_t size() const
+    [[nodiscard]] constexpr isize_t size(this span self)
    {
-        if constexpr (kIsDynamic) { return m_size; }
+        if constexpr (kIsDynamic) { return self.m_size; }
        else { return kSize; }
    }

-    constexpr isize_t size_bytes() const { return size() * size_of<T>; }
+    [[nodiscard]] constexpr isize_t size_bytes(this span self) { return self.size() * size_of<T>; }

-    constexpr bool is_empty() const { return size() == 0; }
+    [[nodiscard]] constexpr bool is_empty(this span self) { return self.size() == 0; }

-    constexpr T* data() const { return m_data; }
+    [[nodiscard]] constexpr T* data(this span self) { return self.m_data; }

-    constexpr contiguous_iterator<T> begin() const
+    [[nodiscard]] constexpr contiguous_iterator<T> begin(this span self)
    {
-        return contiguous_iterator{m_data};
+        return contiguous_iterator{self.m_data};
    }

-    constexpr contiguous_iterator<T> end() const
+    [[nodiscard]] constexpr contiguous_iterator<T> end(this span self)
    {
-        return contiguous_iterator{m_data + size()};
+        return contiguous_iterator{self.m_data + self.size()};
    }

-    constexpr T& operator[](isize_t i) const
+    constexpr T& operator[](this span self, isize_t i)
    {
-        ASL_ASSERT(i >= 0 && i < size());
-        return m_data[i]; // NOLINT(*-pointer-arithmetic)
+        ASL_ASSERT(i >= 0 && i < self.size());
+        return self.m_data[i]; // NOLINT(*-pointer-arithmetic)
    }

    template<isize_t kOffset, isize_t kSubSize = dynamic_size>
-    constexpr auto subspan() const
+    [[nodiscard]] constexpr auto subspan(this span self)
        requires (
            kOffset >= 0 &&
            (kIsDynamic || kOffset <= kSize) &&
            (kIsDynamic || is_dynamic(kSubSize) || kSubSize <= kSize - kOffset)
        )
    {
-        ASL_ASSERT(kOffset <= size());
+        ASL_ASSERT(kOffset <= self.size());

        if constexpr (is_dynamic(kSubSize))
        {
            if constexpr (kIsDynamic)
            {
-                return span<T>(data() + kOffset, size() - kOffset);
+                return span<T>(self.data() + kOffset, self.size() - kOffset);
            }
            else
            {
-                return span<T, kSize - kOffset>(data() + kOffset, size() - kOffset);
+                return span<T, kSize - kOffset>(self.data() + kOffset, self.size() - kOffset);
            }
        }
        else
        {
-            ASL_ASSERT(kSubSize <= size() - kOffset);
-            return span<T, kSubSize>(data() + kOffset, kSubSize);
+            ASL_ASSERT(kSubSize <= self.size() - kOffset);
+            return span<T, kSubSize>(self.data() + kOffset, kSubSize);
        }
    }

-    constexpr span<T> subspan(isize_t offset) const
+    [[nodiscard]] constexpr span<T> subspan(this span self, isize_t offset)
    {
-        ASL_ASSERT(offset <= size());
-        return span<T>{ data() + offset, size() - offset };
+        ASL_ASSERT(offset <= self.size());
+        return span<T>{ self.data() + offset, self.size() - offset };
    }

-    constexpr span<T> subspan(isize_t offset, isize_t sub_size) const
+    [[nodiscard]] constexpr span<T> subspan(this span self, isize_t offset, isize_t sub_size)
    {
-        ASL_ASSERT(offset <= size() && !is_dynamic(sub_size));
-        ASL_ASSERT(sub_size <= size() - offset);
-        return span<T>{ data() + offset, sub_size };
+        ASL_ASSERT(offset <= self.size() && !is_dynamic(sub_size));
+        ASL_ASSERT(sub_size <= self.size() - offset);
+        return span<T>{ self.data() + offset, sub_size };
    }

    template<isize_t kSubSize>
-    constexpr auto first() const
+    [[nodiscard]] constexpr auto first(this span self)
        requires (
            kSubSize >= 0 &&
            (kIsDynamic || kSubSize <= kSize)
        )
    {
-        ASL_ASSERT(kSubSize <= size());
-        return span<T, kSubSize>{ data(), kSubSize };
+        ASL_ASSERT(kSubSize <= self.size());
+        return span<T, kSubSize>{ self.data(), kSubSize };
    }

-    constexpr span<T> first(isize_t sub_size) const
+    [[nodiscard]] constexpr span<T> first(this span self, isize_t sub_size)
    {
-        ASL_ASSERT(sub_size >= 0 && sub_size <= size());
-        return span<T>{ data(), sub_size };
+        ASL_ASSERT(sub_size >= 0 && sub_size <= self.size());
+        return span<T>{ self.data(), sub_size };
    }

    template<isize_t kSubSize>
-    constexpr auto last() const
+    [[nodiscard]] constexpr auto last(this span self)
        requires (
            kSubSize >= 0 &&
            (kIsDynamic || kSubSize <= kSize)
        )
    {
-        ASL_ASSERT(kSubSize <= size());
-        return span<T, kSubSize>{ data() + size() - kSubSize, kSubSize };
+        ASL_ASSERT(kSubSize <= self.size());
+        return span<T, kSubSize>{ self.data() + self.size() - kSubSize, kSubSize };
    }

-    constexpr span<T> last(isize_t sub_size) const
+    [[nodiscard]] constexpr span<T> last(this span self, isize_t sub_size)
    {
-        ASL_ASSERT(sub_size >= 0 && sub_size <= size());
-        return span<T>{ data() + size() - sub_size, sub_size };
+        ASL_ASSERT(sub_size >= 0 && sub_size <= self.size());
+        return span<T>{ self.data() + self.size() - sub_size, sub_size };
    }
 };
+// NOLINTEND(*-convert-member-functions-to-static)

 template<is_object T, isize_t kSize>
 inline span<const byte> as_bytes(span<T, kSize> s)
 {
    return span<const byte>(
-        reinterpret_cast<const byte*>(s.data()),
+        reinterpret_cast<const byte*>(s.data()), // NOLINT(*-reinterpret-cast)
        s.size_bytes());
 }

@ -226,7 +228,7 @@ inline span<byte> as_mutable_bytes(span<T, kSize> s)
    requires (!is_const<T>)
 {
    return span<byte>(
-        reinterpret_cast<byte*>(s.data()),
+        reinterpret_cast<byte*>(s.data()), // NOLINT(*-reinterpret-cast)
        s.size_bytes());
 }

--- a/asl/types/span_tests.cpp
+++ b/asl/types/span_tests.cpp
@ -17,7 +17,7 @@ static_assert(asl::size_of<asl::span<int, 2>> == asl::size_of<void*>);

 ASL_TEST(empty_dynamic)
 {
-    asl::span<int> s;
+    const asl::span<int> s;
    ASL_TEST_EXPECT(s.size() == 0);
    ASL_TEST_EXPECT(s.size_bytes() == 0);
    ASL_TEST_EXPECT(s.is_empty());
@ -26,7 +26,7 @@ ASL_TEST(empty_dynamic)

 ASL_TEST(empty_static)
 {
-    asl::span<int, 0> s;
+    const asl::span<int, 0> s;
    ASL_TEST_EXPECT(s.size() == 0);
    ASL_TEST_EXPECT(s.size_bytes() == 0);
    ASL_TEST_EXPECT(s.is_empty());
@ -35,7 +35,7 @@ ASL_TEST(empty_static)
 ASL_TEST(from_array_dynamic)
 {
    int array[] = {1, 2, 3};
-    asl::span<int> span = array;
+    const asl::span<int> span = array;
    ASL_TEST_ASSERT(span.size() == 3);
    ASL_TEST_EXPECT(span[0] == 1);
    ASL_TEST_EXPECT(span[1] == 2);
@ -56,7 +56,7 @@ static_assert(!asl::constructible_from<asl::span<int32_t, 8>, int32_t(&)[10]>);
 ASL_TEST(from_array_static)
 {
    int array[] = {1, 2, 3};
-    asl::span<int, 3> span = array;
+    const asl::span<int, 3> span = array;
    ASL_TEST_ASSERT(span.size() == 3);
    ASL_TEST_EXPECT(span[0] == 1);
    ASL_TEST_EXPECT(span[1] == 2);
@ -77,21 +77,21 @@ ASL_TEST(conversion)
 {
    int array[] = {1, 2, 3};

-    asl::span<int> span1 = array;
+    const asl::span<int> span1 = array;

-    asl::span<int, 3> span2{span1};
+    const asl::span<int, 3> span2{span1};
    ASL_TEST_ASSERT(span2.size() == 3);
    ASL_TEST_EXPECT(span2[0] == 1);
    ASL_TEST_EXPECT(span2[1] == 2);
    ASL_TEST_EXPECT(span2[2] == 3);

-    asl::span<int> span3 = span2;
+    const asl::span<int> span3 = span2;
    ASL_TEST_ASSERT(span3.size() == 3);
    ASL_TEST_EXPECT(span3[0] == 1);
    ASL_TEST_EXPECT(span3[1] == 2);
    ASL_TEST_EXPECT(span3[2] == 3);

-    asl::span<const int, 3> span4{span2};
+    const asl::span<const int, 3> span4{span2};
    ASL_TEST_ASSERT(span4.size() == 3);
    ASL_TEST_EXPECT(span4[0] == 1);
    ASL_TEST_EXPECT(span4[1] == 2);
@ -138,7 +138,7 @@ static_assert(!IsValidSubspan<asl::span<int, 4>, 2, 3>);
 ASL_TEST(subspan_static_from_static)
 {
    int array[] = {1, 2, 3, 4};
-    asl::span<int, 4> span{array};
+    const asl::span<int, 4> span{array};

    auto s1 = span.subspan<0>();
    ASL_TEST_ASSERT(s1.size() == 4);
@ -164,7 +164,7 @@ ASL_TEST(subspan_static_from_static)
 ASL_TEST(subspan_static_from_dynamic)
 {
    int array[] = {1, 2, 3, 4};
-    asl::span<int> span{array};
+    const asl::span<int> span{array};

    auto s1 = span.subspan<0>();
    ASL_TEST_ASSERT(s1.size() == 4);
@ -190,7 +190,7 @@ ASL_TEST(subspan_static_from_dynamic)
 ASL_TEST(subspan_dynamic)
 {
    int array[] = {1, 2, 3, 4};
-    asl::span<int> span{array};
+    const asl::span<int> span{array};

    auto s1 = span.subspan(0);
    ASL_TEST_ASSERT(s1.size() == 4);
@ -249,7 +249,7 @@ static_assert(!IsValidFirst<asl::span<int, 4>, asl::dynamic_size>);
 ASL_TEST(first_static_from_static)
 {
    int array[] = {1, 2, 3, 4};
-    asl::span<int, 4> span{array};
+    const asl::span<int, 4> span{array};

    auto s1 = span.first<0>();
    ASL_TEST_ASSERT(s1.size() == 0);
@ -270,7 +270,7 @@ ASL_TEST(first_static_from_static)
 ASL_TEST(first_static_from_dynamic)
 {
    int array[] = {1, 2, 3, 4};
-    asl::span<int> span{array};
+    const asl::span<int> span{array};

    auto s1 = span.first<0>();
    ASL_TEST_ASSERT(s1.size() == 0);
@ -291,7 +291,7 @@ ASL_TEST(first_static_from_dynamic)
 ASL_TEST(first_dynamic)
 {
    int array[] = {1, 2, 3, 4};
-    asl::span<int> span{array};
+    const asl::span<int> span{array};

    auto s1 = span.first(0);
    ASL_TEST_ASSERT(s1.size() == 0);
@ -345,7 +345,7 @@ static_assert(!IsValidLast<asl::span<int, 4>, asl::dynamic_size>);
 ASL_TEST(last_static_from_static)
 {
    int array[] = {1, 2, 3, 4};
-    asl::span<int, 4> span{array};
+    const asl::span<int, 4> span{array};

    auto s1 = span.last<0>();
    ASL_TEST_ASSERT(s1.size() == 0);
@ -366,7 +366,7 @@ ASL_TEST(last_static_from_static)
 ASL_TEST(last_static_from_dynamic)
 {
    int array[] = {1, 2, 3, 4};
-    asl::span<int> span{array};
+    const asl::span<int> span{array};

    auto s1 = span.last<0>();
    ASL_TEST_ASSERT(s1.size() == 0);
@ -387,7 +387,7 @@ ASL_TEST(last_static_from_dynamic)
 ASL_TEST(last_dynamic)
 {
    int array[] = {1, 2, 3, 4};
-    asl::span<int> span{array};
+    const asl::span<int> span{array};

    auto s1 = span.last(0);
    ASL_TEST_ASSERT(s1.size() == 0);
@ -416,8 +416,8 @@ static_assert(HasAsMutableBytes<const int*>);
 ASL_TEST(as_bytes)
 {
     uint32_t data[] = {0x01020304, 0x05060708};
-     asl::span s1(data);
-     asl::span s2 = asl::as_bytes(s1);
+     const asl::span s1(data);
+     const asl::span s2 = asl::as_bytes(s1);

     ASL_TEST_ASSERT(s2.size() == 8);
     ASL_TEST_ASSERT(static_cast<int>(s2[0]) == 0x04);
@ -433,8 +433,8 @@ ASL_TEST(as_bytes)
 ASL_TEST(as_mutable_bytes)
 {
     uint32_t data[] = {0x01020304, 0x05060708};
-     asl::span s1(data);
-     asl::span s2 = asl::as_mutable_bytes(s1);
+     const asl::span s1(data);
+     const asl::span s2 = asl::as_mutable_bytes(s1);

     ASL_TEST_ASSERT(s2.size() == 8);
     ASL_TEST_ASSERT(static_cast<int>(s2[0]) == 0x04);
--- a/asl/types/status.cpp
+++ b/asl/types/status.cpp
@ -11,9 +11,11 @@

 // @Todo Use custom allocator
 using Allocator = asl::DefaultAllocator;
+
+// NOLINTNEXTLINE(*-non-const-global-variables)
 static Allocator g_allocator{};

-namespace
+namespace asl
 {

 struct StatusInternal
@ -23,7 +25,7 @@ struct StatusInternal
    asl::atomic<int32_t> ref_count;

    constexpr StatusInternal(asl::string<Allocator>&& msg_, asl::status_code code_)
-        : msg{ASL_MOVE(msg_)}
+        : msg{std::move(msg_)}
        , code{code_}
    {
        ASL_ASSERT(code != asl::status_code::ok);
@ -31,7 +33,7 @@ struct StatusInternal
    }
 };

-} // anonymous namespace
+}  // namespace asl

 asl::status::status(status_code code, string_view msg)
    : m_payload{alloc_new<StatusInternal>(g_allocator, msg, code)}
@ -41,36 +43,35 @@ asl::status::status(status_code code, string_view fmt, span<format_internals::ty
 {
    StringWriter<Allocator> sink{g_allocator};
    format_internals::format(&sink, fmt, args);
-    m_payload = alloc_new<StatusInternal>(g_allocator, ASL_MOVE(sink).finish(), code);
+    m_payload = alloc_new<StatusInternal>(g_allocator, std::move(sink).finish(), code);
 }

 asl::status_code asl::status::code_internal() const
 {
    ASL_ASSERT(!is_inline());
-    return reinterpret_cast<const StatusInternal*>(m_payload)->code;
+    return m_payload->code;
 }

 asl::string_view asl::status::message_internal() const
 {
    ASL_ASSERT(!is_inline());
-    return reinterpret_cast<const StatusInternal*>(m_payload)->msg;
+    return m_payload->msg;
 }

 void asl::status::ref()
 {
    ASL_ASSERT(!is_inline());
-    auto* internal = reinterpret_cast<StatusInternal*>(m_payload);
-    atomic_fetch_increment(&internal->ref_count, memory_order::relaxed);
+    atomic_fetch_increment(&m_payload->ref_count, memory_order::relaxed);
 }

 void asl::status::unref()
 {
    ASL_ASSERT(!is_inline());
-    auto* internal = reinterpret_cast<StatusInternal*>(m_payload);
-    if (atomic_fetch_decrement(&internal->ref_count, memory_order::release) == 1)
+    if (atomic_fetch_decrement(&m_payload->ref_count, memory_order::release) == 1)
    {
        atomic_fence(memory_order::acquire);
-        alloc_delete(g_allocator, internal);
+        alloc_delete(g_allocator, m_payload);
+        m_payload = nullptr;
    }
 }

--- a/asl/types/status.hpp
+++ b/asl/types/status.hpp
@ -22,15 +22,17 @@ enum class status_code : uint8_t
    invalid_argument = 4,
 };

+struct StatusInternal;
+
 class status
 {
-    void* m_payload{};
+    StatusInternal* m_payload{};

-    static constexpr void* status_to_payload(status_code code)
+    static constexpr StatusInternal* status_to_payload(status_code code)
    {
        return code == status_code::ok
            ? nullptr
-            : bit_cast<void*>((static_cast<uintptr_t>(code) << 1) | 1);
+            : bit_cast<StatusInternal*>((static_cast<uintptr_t>(code) << 1) | 1);
    }

    static constexpr status_code payload_to_status(void* payload)
@ -38,12 +40,12 @@ class status
        return static_cast<status_code>(bit_cast<uintptr_t>(payload) >> 1);
    }

-    constexpr bool is_inline() const
+    [[nodiscard]] constexpr bool is_inline() const
    {
        return m_payload == nullptr || (bit_cast<uintptr_t>(m_payload) & 1) != 0;
    }

-    constexpr status_code code_inline() const
+    [[nodiscard]] constexpr status_code code_inline() const
    {
        ASL_ASSERT(is_inline());
        if (m_payload == nullptr)
@ -53,8 +55,8 @@ class status
        return payload_to_status(m_payload);
    }

-    status_code code_internal() const;
-    string_view message_internal() const;
+    [[nodiscard]] status_code code_internal() const;
+    [[nodiscard]] string_view message_internal() const;

    void ref();
    void unref();
@ -103,17 +105,17 @@ public:
        return *this;
    }

-    constexpr bool ok() const
+    [[nodiscard]] constexpr bool ok() const
    {
        return m_payload == nullptr;
    }

-    constexpr status_code code() const
+    [[nodiscard]] constexpr status_code code() const
    {
        return is_inline() ? code_inline() : code_internal();
    }

-    constexpr string_view message() const
+    [[nodiscard]] constexpr string_view message() const
    {
        if (!is_inline())
        {
@ -122,7 +124,7 @@ public:
        return {};
    }

-    constexpr status&& throw_status() && { return ASL_MOVE(*this); }
+    constexpr status&& throw_status() && { return std::move(*this); }

    friend void AslFormat(Formatter& f, const status&);

@ -131,9 +133,9 @@ public:
    {
        if (s.is_inline())
        {
-            return H::combine(ASL_MOVE(h), s.code());
+            return H::combine(std::move(h), s.code());
        }
-        return H::combine(ASL_MOVE(h), s.code(), s.message());
+        return H::combine(std::move(h), s.code(), s.message());
    }
 };

@ -156,6 +158,6 @@ ASL_DEFINE_ERROR_(internal)
 ASL_DEFINE_ERROR_(runtime)
 ASL_DEFINE_ERROR_(invalid_argument)

-#define ASL_TRY(VALUE) if (VALUE.ok()) {} else { return ASL_MOVE(VALUE).throw_status(); }
+#define ASL_TRY(VALUE) if ((VALUE).ok()) {} else { return std::move(VALUE).throw_status(); }

 } // namespace asl
--- a/asl/types/status_or.hpp
+++ b/asl/types/status_or.hpp
@ -33,11 +33,11 @@ public:

    constexpr status_or(status_or&& other)
        requires move_constructible<T>
-        : m_status{ASL_MOVE(other.m_status)}
+        : m_status{std::move(other.m_status)}
    {
        if (other.ok())
        {
-            m_value.construct_unsafe(ASL_MOVE(other.m_value.as_init_unsafe()));
+            m_value.construct_unsafe(std::move(other.m_value.as_init_unsafe()));
        }
    }

@ -75,7 +75,7 @@ public:
            {
                if (other.ok())
                {
-                    m_value.assign_unsafe(ASL_MOVE(other.m_value.as_init_unsafe()));
+                    m_value.assign_unsafe(std::move(other.m_value.as_init_unsafe()));
                }
                else
                {
@ -84,9 +84,9 @@ public:
            }
            else if (other.ok())
            {
-                m_value.construct_unsafe(ASL_MOVE(other.m_value.as_init_unsafe()));
+                m_value.construct_unsafe(std::move(other.m_value.as_init_unsafe()));
            }
-            m_status = ASL_MOVE(other.m_status);
+            m_status = std::move(other.m_status);
        }
        return *this;
    }
@ -99,14 +99,14 @@ public:
        }
    }

-    // NOLINTNEXTLINE(*-explicit-conversions)
+    // NOLINTNEXTLINE(*explicit*)
    constexpr status_or(const status& status) : m_status{status}
    {
        ASL_ASSERT_RELEASE(!m_status.ok());
    }

-    // NOLINTNEXTLINE(*-explicit-conversions)
-    constexpr status_or(status&& status) : m_status{ASL_MOVE(status)}
+    // NOLINTNEXTLINE(*explicit*)
+    constexpr status_or(status&& status) : m_status{std::move(status)}
    {
        ASL_ASSERT_RELEASE(!m_status.ok());
    }
@ -114,7 +114,7 @@ public:
    status_or& operator=(status status) = delete;

    template<typename U = T>
-    constexpr explicit (!convertible_from<T, U&&>)
+    constexpr explicit (!convertible_to<U&&, T>)
    status_or(U&& value)
        requires (
            constructible_from<T, U&&> &&
@ -122,35 +122,35 @@ public:
            !same_as<un_cvref_t<U>, status>
        )
        : m_status{status_code::ok}
-        , m_value{in_place, ASL_FWD(value)}
+        , m_value{in_place, std::forward<U>(value)}
    {}

-    constexpr bool ok() const { return m_status.ok(); }
+    [[nodiscard]] constexpr bool ok() const { return m_status.ok(); }

-    constexpr status_code code() const { return m_status.code(); }
+    [[nodiscard]] constexpr status_code code() const { return m_status.code(); }

-    constexpr string_view message() const { return m_status.message(); }
+    [[nodiscard]] constexpr string_view message() const { return m_status.message(); }

-    constexpr status&& throw_status() && { return ASL_MOVE(m_status); }
+    constexpr status&& throw_status() && { return std::move(m_status); }

    constexpr auto&& value(this auto&& self)
    {
        ASL_ASSERT_RELEASE(self.ok());
-        return ASL_FWD(self).m_value.as_init_unsafe();
+        return std::forward<decltype(self)>(self).m_value.as_init_unsafe();
    }

    template<typename U>
    constexpr T value_or(U&& other_value) const&
-        requires copy_constructible<T> && convertible_from<T, U&&>
+        requires copy_constructible<T> && convertible_to<U&&, T>
    {
-        return ok() ? value() : static_cast<T>(ASL_FWD(other_value));
+        return ok() ? value() : static_cast<T>(std::forward<U>(other_value));
    }

    template<typename U>
    constexpr T value_or(U&& other_value) &&
-        requires move_constructible<T> && convertible_from<T, U&&>
+        requires move_constructible<T> && convertible_to<U&&, T>
    {
-        return ok() ? ASL_MOVE(value()) : static_cast<T>(ASL_FWD(other_value));
+        return ok() ? std::move(value()) : static_cast<T>(std::forward<U>(other_value));
    }

    friend void AslFormat(Formatter& f, const status_or& status)
@ -164,9 +164,9 @@ public:
    {
        if (s.ok())
        {
-            return H::combine(ASL_MOVE(h), s.m_status, s.value());
+            return H::combine(std::move(h), s.m_status, s.value());
        }
-        return H::combine(ASL_MOVE(h), s.m_status);
+        return H::combine(std::move(h), s.m_status);
    }
 };

--- a/asl/types/status_or_tests.cpp
+++ b/asl/types/status_or_tests.cpp
@ -20,24 +20,24 @@ static_assert(!asl::moveable<asl::status_or<Pinned>>);

 ASL_TEST(ok)
 {
-    asl::status_or<int> s = 6;
+    const  asl::status_or<int> s = 6;
    ASL_TEST_EXPECT(s.ok());
    ASL_TEST_EXPECT(s.code() == asl::status_code::ok);
 }

 ASL_TEST(from_status)
 {
-    asl::status_or<char> s = asl::internal_error();
+    const asl::status_or<char> s = asl::internal_error();
    ASL_TEST_EXPECT(!s.ok());
    ASL_TEST_EXPECT(s.code() == asl::status_code::internal);
    ASL_TEST_EXPECT(s.message() == ""_sv);

-    asl::status_or<int> s2 = asl::internal_error("oh no");
+    const asl::status_or<int> s2 = asl::internal_error("oh no");
    ASL_TEST_EXPECT(!s2.ok());
    ASL_TEST_EXPECT(s2.code() == asl::status_code::internal);
    ASL_TEST_EXPECT(s2.message() == "oh no"_sv);

-    asl::status_or<int> s3 = asl::internal_error("{} {}", 1, 2);
+    const asl::status_or<int> s3 = asl::internal_error("{} {}", 1, 2);
    ASL_TEST_EXPECT(!s3.ok());
    ASL_TEST_EXPECT(s3.code() == asl::status_code::internal);
    ASL_TEST_EXPECT(s3.message() == "1 2"_sv);
@ -52,11 +52,11 @@ ASL_TEST(destructor)
        ASL_TEST_EXPECT(s.ok());
        ASL_TEST_EXPECT(!d);

-        asl::status_or s2 = ASL_MOVE(s);
-        ASL_TEST_EXPECT(s.ok());
+        asl::status_or s2 = std::move(s);
+        ASL_TEST_EXPECT(s2.ok());
        ASL_TEST_EXPECT(!d);

-        s = ASL_MOVE(s2);
+        s = std::move(s2);
        ASL_TEST_EXPECT(s.ok());
        ASL_TEST_EXPECT(!d);
    }
@ -79,8 +79,8 @@ ASL_TEST(copy)

 ASL_TEST(value_or)
 {
-    asl::status_or<int> s = 7;
-    asl::status_or<int> s2 = asl::internal_error();
+    const asl::status_or<int> s = 7;
+    const asl::status_or<int> s2 = asl::internal_error();

    ASL_TEST_EXPECT(s.value_or(45) == 7);
    ASL_TEST_EXPECT(s2.value_or(45) == 45);
--- a/asl/types/status_tests.cpp
+++ b/asl/types/status_tests.cpp
@ -9,14 +9,14 @@

 ASL_TEST(simple_ok)
 {
-    asl::status s = asl::ok();
+    const asl::status s = asl::ok();
    ASL_TEST_ASSERT(s.ok());
    ASL_TEST_ASSERT(s.code() == asl::status_code::ok);
 }

 ASL_TEST(simple_code)
 {
-    asl::status s = asl::runtime_error();
+    const asl::status s = asl::runtime_error();
    ASL_TEST_ASSERT(!s.ok());
    ASL_TEST_ASSERT(s.code() == asl::status_code::runtime);
    ASL_TEST_ASSERT(s.message() == ""_sv);
@ -24,7 +24,7 @@ ASL_TEST(simple_code)

 ASL_TEST(with_message)
 {
-    asl::status s = asl::internal_error("We done goofed");
+    const asl::status s = asl::internal_error("We done goofed");
    ASL_TEST_ASSERT(!s.ok());
    ASL_TEST_ASSERT(s.code() == asl::status_code::internal);
    ASL_TEST_ASSERT(s.message() == "We done goofed"_sv);
@ -32,8 +32,8 @@ ASL_TEST(with_message)

 ASL_TEST(copy_inline)
 {
-    asl::status s = asl::ok();
-    asl::status s2 = asl::internal_error();
+    const asl::status s = asl::ok();
+    const asl::status s2 = asl::internal_error();

    asl::status s3 = s;
    ASL_TEST_ASSERT(s3.code() == asl::status_code::ok);
@ -47,7 +47,7 @@ ASL_TEST(copy_message)
    asl::status s2 = asl::ok();

    {
-        asl::status s = asl::internal_error("Oh no!");
+        const asl::status s = asl::internal_error("Oh no!");
        ASL_TEST_ASSERT(!s.ok());
        ASL_TEST_ASSERT(s.code() == asl::status_code::internal);
        ASL_TEST_ASSERT(s.message() == "Oh no!"_sv);
--- a/todo.txt
+++ b/todo.txt
@ -1 +1 @@
-
+C++26: constexpr cast from void* https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2023/p2738r1.pdf
--- a/tools/fix_line_endings.py
+++ b/tools/fix_line_endings.py
@ -12,6 +12,7 @@ import time
 TO_FIX = [
    ".bazelrc",
    ".clang-tidy",
+    ".clangd",
    ".gitignore",
    "**/*.hpp",
    "**/*.h",
--- a/vendor/dragonbox/BUILD.bazel
+++ b/vendor/dragonbox/BUILD.bazel
@ -18,7 +18,7 @@ cc_library(
    name = "dragonbox",
    hdrs = ["dragonbox.h"],
    includes = ["."],
-    visibility = ["//:__subpackages__"],
+    visibility = ["//asl:__subpackages__"],
    applicable_licenses = [
        ":license",
    ],
--- a/vendor/fast_float/BUILD.bazel
+++ b/vendor/fast_float/BUILD.bazel
@ -0,0 +1,25 @@
+# Copyright 2025 Steven Le Rouzic
+#
+# SPDX-License-Identifier: BSD-3-Clause
+
+load("@rules_license//rules:license.bzl", "license")
+
+license(
+    name = "license",
+    license_kinds = [
+        "@rules_license//licenses/spdx:MIT",
+    ],
+    license_text = "LICENSE.txt",
+    package_name = "fast_float",
+    package_url = "https://github.com/fastfloat/fast_float",
+)
+
+cc_library(
+    name = "fast_float",
+    hdrs = ["fast_float.h"],
+    includes = ["."],
+    visibility = ["//asl:__subpackages__"],
+    applicable_licenses = [
+        ":license",
+    ],
+)
--- a/vendor/fast_float/LICENSE.txt
+++ b/vendor/fast_float/LICENSE.txt
@ -0,0 +1,27 @@
+MIT License
+
+Copyright (c) 2021 The fast_float authors
+
+Permission is hereby granted, free of charge, to any
+person obtaining a copy of this software and associated
+documentation files (the "Software"), to deal in the
+Software without restriction, including without
+limitation the rights to use, copy, modify, merge,
+publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software
+is furnished to do so, subject to the following
+conditions:
+
+The above copyright notice and this permission notice
+shall be included in all copies or substantial portions
+of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
+ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
+TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
+PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
+SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
+IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.
--- a/vendor/fast_float/fast_float.h
+++ b/vendor/fast_float/fast_float.h
Author	SHA1	Message	Date
Steven Le Rouzic	00ea14788f	Fix a bunch of warnings	2025-07-06 17:05:36 +02:00
Steven Le Rouzic	bcdad5b876	Add numbers parsing	2025-07-04 20:44:04 +02:00
Steven Le Rouzic	cca2e26724	Add integer traits	2025-07-04 18:22:03 +02:00
Steven Le Rouzic	195f20ff17	Add SparseHandlePool	2025-07-03 18:35:25 +02:00
Steven Le Rouzic	a78e24e9eb	Add DenseHandlePool	2025-07-03 18:34:45 +02:00
Steven Le Rouzic	43ab95880d	Add pop method to chunked_buffer	2025-06-26 18:25:00 +02:00
Steven Le Rouzic	47c6677405	Add IndexPool	2025-06-26 12:37:02 +02:00
Steven Le Rouzic	92f908ee1b	Add index_pool_handle	2025-06-18 00:05:33 +02:00
Steven Le Rouzic	30237bb78f	Add index_pool_config	2025-06-18 00:05:33 +02:00
Steven Le Rouzic	8f59f113e8	Fix test execution after a fail	2025-06-18 00:05:33 +02:00
Steven Le Rouzic	afb237c513	Add smallest_unsigned_integer_type_for_width	2025-06-14 12:56:11 +02:00
Steven Le Rouzic	19e2164441	Use the new Bazel registry	2025-06-04 21:59:48 +02:00
Steven Le Rouzic	b8a87223bb	Add compile-time configuration for build settings	2025-05-26 22:38:04 +02:00
Steven Le Rouzic	a1db1cd9e2	Implement chunked_buffer	2025-05-26 00:48:06 +02:00
Steven Le Rouzic	54b95b1662	Buffer type has to be moveable, always	2025-05-17 23:01:51 +02:00
Steven Le Rouzic	e7e7023340	Fix build on Linux	2025-05-16 22:59:09 +02:00
Steven Le Rouzic	f7a2699ac0	Add and use copy_const_t	2025-05-14 00:41:51 +02:00
Steven Le Rouzic	088e03708a	Add array	2025-05-14 00:41:51 +02:00
Steven Le Rouzic	5bca42b049	Version 0.4.0	2025-05-08 00:16:26 +02:00
Steven Le Rouzic	e1ba7dd7a9	Add enum underlying utilities	2025-05-08 00:15:26 +02:00
Steven Le Rouzic	837f696971	Update some Bazel rules	2025-04-11 19:57:37 +02:00
Steven Le Rouzic	afbfd0e781	Add numeric library	2025-04-03 23:27:39 +02:00
Steven Le Rouzic	0776012d09	Add bit library	2025-04-03 00:34:54 +02:00
Steven Le Rouzic	4f8cbd442a	Add invoke_r & co	2025-03-26 21:52:00 +01:00
Steven Le Rouzic	2d309a2cff	Separate allocator from memory	2025-03-26 21:35:18 +01:00
Steven Le Rouzic	f19d93a69a	Improve implementation of invoke	2025-03-26 18:54:54 +01:00
Steven Le Rouzic	e034efe8bd	Add member pointer stuff to meta lib	2025-03-26 18:54:53 +01:00
Steven Le Rouzic	2c457c4275	Add address_of	2025-03-26 18:54:49 +01:00
Steven Le Rouzic	95598e24e1	Add missing license headers	2025-03-22 19:36:26 +01:00
Steven Le Rouzic	99c8ae9530	Enable platform specific config	2025-03-22 19:31:09 +01:00
Steven Le Rouzic	781877bd26	Add function_ref	2025-03-22 19:24:40 +01:00
Steven Le Rouzic	c692909ff3	Add function	2025-03-21 23:46:39 +01:00
Steven Le Rouzic	a665c590d5	Add decay	2025-03-20 19:29:08 +01:00
Steven Le Rouzic	7023c0cc9a	Use launder to access buffer SSO storage	2025-03-18 23:42:30 +01:00
Steven Le Rouzic	4884b59433	Make status implementation more correct wrt type punning	2025-03-18 22:39:35 +01:00
Steven Le Rouzic	a7475b6af2	Remove redundant methods in hash_map	2025-03-14 18:59:32 +01:00
Steven Le Rouzic	8b6f57dc6a	Pass string_view, span, and iterators by value	2025-03-14 18:57:02 +01:00
Steven Le Rouzic	d1bb5a83f6	Use inheritance for string implementation	2025-03-14 18:56:58 +01:00
Steven Le Rouzic	4630cb5237	Add missing is_empty methods	2025-03-14 18:53:37 +01:00
Steven Le Rouzic	dce2c187ec	Upgrade to Clang 20.1.0	2025-03-14 18:53:35 +01:00
Steven Le Rouzic	cbade33906	Some more shit	2025-03-12 22:32:38 +01:00
Steven Le Rouzic	c8b73031d8	Remove convertible_from	2025-03-12 00:08:18 +01:00
Steven Le Rouzic	af4e29f8c0	Remake deref	2025-03-11 23:51:51 +01:00
Steven Le Rouzic	636882316b	Some work on clang-tidy-ing things up	2025-03-07 00:00:43 +01:00
Steven Le Rouzic	f0cccbe328	Replace ASL_MOVE, ASL_FWD, and ASL_FWD_LIKE by their std:: equivalent This is because some compiler stuff and diagnostics tools rely on those symboles being what they are.	2025-03-06 22:56:56 +01:00
				`@ -1 +1 @@`

				`C++26: constexpr cast from void* https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2023/p2738r1.pdf`