init

wip wip, pt2 wip, pt3
author: Stefan Weigl-Bosker <stefan@s00.xyz> 2026-01-05 12:40:09 -0500
committer: Stefan Weigl-Bosker <stefan@s00.xyz> 2026-01-10 15:37:46 -0500
commit: d4b629cc275769c2553db819643849cda2395a17 (patch)
tree: 6dcc5d0c886945f8b58b4d8fd6c7eea4bb1b194d
download: compiler-d4b629cc275769c2553db819643849cda2395a17.tar.gz
24 files changed, 1179 insertions, 0 deletions
diff --git a/.bazelrc b/.bazelrc
new file mode 100644
index 0000000..9149678
--- /dev/null
+++ b/.bazelrc
@@ -0,0 +1,2 @@
+common --shell_executable=/nix/store/1jzhbwq5rjjaqa75z88ws2b424vh7m53-bash-5.2p32/bin/bash
+build --cxxopt='-std=c++23'
diff --git a/.clang-format b/.clang-format
new file mode 100644
index 0000000..76cc928
--- /dev/null
+++ b/.clang-format
@@ -0,0 +1,3 @@
+BasedOnStyle: LLVM
+AlwaysBreakTemplateDeclarations: Yes
+LineEnding: LF
diff --git a/.clang-tidy b/.clang-tidy
new file mode 100644
index 0000000..c419033
--- /dev/null
+++ b/.clang-tidy
@@ -0,0 +1,72 @@
+InheritParentConfig: true
+Checks: >
+        bugprone-argument-comment,
+        bugprone-assert-side-effect,
+        bugprone-branch-clone,
+        bugprone-copy-constructor-init,
+        bugprone-dangling-handle,
+        bugprone-dynamic-static-initializers,
+        bugprone-macro-parentheses,
+        bugprone-macro-repeated-side-effects,
+        bugprone-misplaced-widening-cast,
+        bugprone-move-forwarding-reference,
+        bugprone-multiple-statement-macro,
+        bugprone-suspicious-semicolon,
+        bugprone-swapped-arguments,
+        bugprone-terminating-continue,
+        bugprone-unused-raii,
+        bugprone-unused-return-value,
+        misc-redundant-expression,
+        misc-static-assert,
+        misc-unused-using-decls,
+        modernize-use-bool-literals,
+        modernize-loop-convert,
+        modernize-make-unique,
+        modernize-raw-string-literal,
+        modernize-use-equals-default,
+        modernize-use-default-member-init,
+        modernize-use-emplace,
+        modernize-use-nullptr,
+        modernize-use-override,
+        modernize-use-using,
+        performance-for-range-copy,
+        performance-implicit-conversion-in-loop,
+        performance-inefficient-algorithm,
+        performance-inefficient-vector-operation,
+        performance-move-const-arg,
+        performance-no-automatic-move,
+        performance-trivially-destructible,
+        performance-unnecessary-copy-initialization,
+        performance-unnecessary-value-param,
+        readability-avoid-const-params-in-decls,
+        readability-const-return-type,
+        readability-container-size-empty,
+        readability-inconsistent-declaration-parameter-name,
+        readability-misleading-indentation,
+        readability-redundant-control-flow,
+        readability-redundant-smartptr-get,
+        readability-simplify-boolean-expr,
+        readability-simplify-subscript-expr,
+        readability-use-anyofallof
+
+
+CheckOptions:
+  - key:             readability-identifier-naming.MemberCase
+    value:           lower_case
+  - key:             readability-identifier-naming.VariableCase
+    value:           lower_case
+  - key:             readability-identifier-naming.LocalVariableCase
+    value:           lower_case
+  - key:             readability-identifier-naming.ParameterCase
+    value:           lower_case
+  - key:             readability-identifier-naming.FunctionCase
+    value:           camelBack
+  - key:             readability-identifier-naming.ClassCase
+    value:           CamelCase
+  - key:             readability-identifier-naming.StructCase
+    value:           CamelCase
+  - key:             readability-identifier-naming.UnionCase
+    value:           CamelCase
+  - key:             readability-identifier-naming.ConstantCase
+    value:           UPPER_CASE
+
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..b267e53
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,7 @@
+# Ignore all bazel-* symlinks. There is no full list since this can change
+# based on the name of the directory bazel is cloned into.
+/bazel-*
+# Ignore outputs generated during Bazel bootstrapping.
+/output/
+user.bazelrc
+/out
diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
new file mode 100644
index 0000000..2d278e4
--- /dev/null
+++ b/.pre-commit-config.yaml
@@ -0,0 +1,6 @@
+repos:
+  - repo: https://github.com/pre-commit/mirrors-clang-format
+    rev: v17.0.6
+    hooks:
+      - id: clang-format
+        files: "\\.(c|cc|cpp|cxx|h|hh|hpp)$"
diff --git a/BUILD b/BUILD
new file mode 100644
index 0000000..6cbf83c
--- /dev/null
+++ b/BUILD
@@ -0,0 +1,9 @@
+load("@hedron_compile_commands//:refresh_compile_commands.bzl", "refresh_compile_commands")
+
+refresh_compile_commands(
+    name = "refresh_compile_commands",
+
+    targets = {
+      "//willow:willow": "",
+    },
+)
diff --git a/LICENSE b/LICENSE
new file mode 100644
index 0000000..ddc8442
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,15 @@
+ISC License
+
+Copyright (c) 2026 Stefan Weigl-Bosker <stefan@s00.xyz>
+
+Permission to use, copy, modify, and/or distribute this software for any
+purpose with or without fee is hereby granted, provided that the above
+copyright notice and this permission notice appear in all copies.
+
+THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
+REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
+INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+PERFORMANCE OF THIS SOFTWARE.
diff --git a/MODULE.bazel b/MODULE.bazel
new file mode 100644
index 0000000..4e9fd6e
--- /dev/null
+++ b/MODULE.bazel
@@ -0,0 +1,19 @@
+module(
+  name = "compiler",
+  version = "0.0.1",
+)
+
+bazel_dep(name = "rules_cc", version = "0.2.16")
+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 = "abb61a688167623088f8768cc9264798df6a9d10",
+)
+
+bazel_dep(name = "willow", version = "0.0.1")
+
+local_path_override(
+  module_name = "willow",
+  path = "willow",
+)
diff --git a/MODULE.bazel.lock b/MODULE.bazel.lock
new file mode 100644
index 0000000..aafa0b4
--- /dev/null
+++ b/MODULE.bazel.lock
@@ -0,0 +1,207 @@
+{
+  "lockFileVersion": 24,
+  "registryFileHashes": {
+    "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",
+    "https://bcr.bazel.build/modules/abseil-cpp/20230125.1/MODULE.bazel": "89047429cb0207707b2dface14ba7f8df85273d484c2572755be4bab7ce9c3a0",
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+    "https://bcr.bazel.build/modules/bazel_features/1.1.1/MODULE.bazel": "27b8c79ef57efe08efccbd9dd6ef70d61b4798320b8d3c134fd571f78963dbcd",
+    "https://bcr.bazel.build/modules/bazel_features/1.11.0/MODULE.bazel": "f9382337dd5a474c3b7d334c2f83e50b6eaedc284253334cf823044a26de03e8",
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+    "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",
+    "https://bcr.bazel.build/modules/rules_java/4.0.0/MODULE.bazel": "5a78a7ae82cd1a33cef56dc578c7d2a46ed0dca12643ee45edbb8417899e6f74",
+    "https://bcr.bazel.build/modules/rules_java/5.3.5/MODULE.bazel": "a4ec4f2db570171e3e5eb753276ee4b389bae16b96207e9d3230895c99644b86",
+    "https://bcr.bazel.build/modules/rules_java/6.0.0/MODULE.bazel": "8a43b7df601a7ec1af61d79345c17b31ea1fedc6711fd4abfd013ea612978e39",
+    "https://bcr.bazel.build/modules/rules_java/6.4.0/MODULE.bazel": "e986a9fe25aeaa84ac17ca093ef13a4637f6107375f64667a15999f77db6c8f6",
+    "https://bcr.bazel.build/modules/rules_java/6.5.2/MODULE.bazel": "1d440d262d0e08453fa0c4d8f699ba81609ed0e9a9a0f02cd10b3e7942e61e31",
+    "https://bcr.bazel.build/modules/rules_java/7.10.0/MODULE.bazel": "530c3beb3067e870561739f1144329a21c851ff771cd752a49e06e3dc9c2e71a",
+    "https://bcr.bazel.build/modules/rules_java/7.12.2/MODULE.bazel": "579c505165ee757a4280ef83cda0150eea193eed3bef50b1004ba88b99da6de6",
+    "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/8.14.0/MODULE.bazel": "717717ed40cc69994596a45aec6ea78135ea434b8402fb91b009b9151dd65615",
+    "https://bcr.bazel.build/modules/rules_java/8.14.0/source.json": "8a88c4ca9e8759da53cddc88123880565c520503321e2566b4e33d0287a3d4bc",
+    "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",
+    "https://bcr.bazel.build/modules/rules_jvm_external/5.3/MODULE.bazel": "bf93870767689637164657731849fb887ad086739bd5d360d90007a581d5527d",
+    "https://bcr.bazel.build/modules/rules_jvm_external/6.1/MODULE.bazel": "75b5fec090dbd46cf9b7d8ea08cf84a0472d92ba3585b476f44c326eda8059c4",
+    "https://bcr.bazel.build/modules/rules_jvm_external/6.3/MODULE.bazel": "c998e060b85f71e00de5ec552019347c8bca255062c990ac02d051bb80a38df0",
+    "https://bcr.bazel.build/modules/rules_jvm_external/6.3/source.json": "6f5f5a5a4419ae4e37c35a5bb0a6ae657ed40b7abc5a5189111b47fcebe43197",
+    "https://bcr.bazel.build/modules/rules_kotlin/1.9.0/MODULE.bazel": "ef85697305025e5a61f395d4eaede272a5393cee479ace6686dba707de804d59",
+    "https://bcr.bazel.build/modules/rules_kotlin/1.9.6/MODULE.bazel": "d269a01a18ee74d0335450b10f62c9ed81f2321d7958a2934e44272fe82dcef3",
+    "https://bcr.bazel.build/modules/rules_kotlin/1.9.6/source.json": "2faa4794364282db7c06600b7e5e34867a564ae91bda7cae7c29c64e9466b7d5",
+    "https://bcr.bazel.build/modules/rules_license/0.0.3/MODULE.bazel": "627e9ab0247f7d1e05736b59dbb1b6871373de5ad31c3011880b4133cafd4bd0",
+    "https://bcr.bazel.build/modules/rules_license/0.0.7/MODULE.bazel": "088fbeb0b6a419005b89cf93fe62d9517c0a2b8bb56af3244af65ecfe37e7d5d",
+    "https://bcr.bazel.build/modules/rules_license/1.0.0/MODULE.bazel": "a7fda60eefdf3d8c827262ba499957e4df06f659330bbe6cdbdb975b768bb65c",
+    "https://bcr.bazel.build/modules/rules_license/1.0.0/source.json": "a52c89e54cc311196e478f8382df91c15f7a2bfdf4c6cd0e2675cc2ff0b56efb",
+    "https://bcr.bazel.build/modules/rules_pkg/0.7.0/MODULE.bazel": "df99f03fc7934a4737122518bb87e667e62d780b610910f0447665a7e2be62dc",
+    "https://bcr.bazel.build/modules/rules_pkg/1.0.1/MODULE.bazel": "5b1df97dbc29623bccdf2b0dcd0f5cb08e2f2c9050aab1092fd39a41e82686ff",
+    "https://bcr.bazel.build/modules/rules_pkg/1.0.1/source.json": "bd82e5d7b9ce2d31e380dd9f50c111d678c3bdaca190cb76b0e1c71b05e1ba8a",
+    "https://bcr.bazel.build/modules/rules_proto/4.0.0/MODULE.bazel": "a7a7b6ce9bee418c1a760b3d84f83a299ad6952f9903c67f19e4edd964894e06",
+    "https://bcr.bazel.build/modules/rules_proto/5.3.0-21.7/MODULE.bazel": "e8dff86b0971688790ae75528fe1813f71809b5afd57facb44dad9e8eca631b7",
+    "https://bcr.bazel.build/modules/rules_proto/6.0.2/MODULE.bazel": "ce916b775a62b90b61888052a416ccdda405212b6aaeb39522f7dc53431a5e73",
+    "https://bcr.bazel.build/modules/rules_proto/7.0.2/MODULE.bazel": "bf81793bd6d2ad89a37a40693e56c61b0ee30f7a7fdbaf3eabbf5f39de47dea2",
+    "https://bcr.bazel.build/modules/rules_proto/7.0.2/source.json": "1e5e7260ae32ef4f2b52fd1d0de8d03b606a44c91b694d2f1afb1d3b28a48ce1",
+    "https://bcr.bazel.build/modules/rules_python/0.10.2/MODULE.bazel": "cc82bc96f2997baa545ab3ce73f196d040ffb8756fd2d66125a530031cd90e5f",
+    "https://bcr.bazel.build/modules/rules_python/0.23.1/MODULE.bazel": "49ffccf0511cb8414de28321f5fcf2a31312b47c40cc21577144b7447f2bf300",
+    "https://bcr.bazel.build/modules/rules_python/0.25.0/MODULE.bazel": "72f1506841c920a1afec76975b35312410eea3aa7b63267436bfb1dd91d2d382",
+    "https://bcr.bazel.build/modules/rules_python/0.28.0/MODULE.bazel": "cba2573d870babc976664a912539b320cbaa7114cd3e8f053c720171cde331ed",
+    "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/0.40.0/source.json": "939d4bd2e3110f27bfb360292986bb79fd8dcefb874358ccd6cdaa7bda029320",
+    "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",
+    "https://bcr.bazel.build/modules/stardoc/0.5.3/MODULE.bazel": "c7f6948dae6999bf0db32c1858ae345f112cacf98f174c7a8bb707e41b974f1c",
+    "https://bcr.bazel.build/modules/stardoc/0.5.6/MODULE.bazel": "c43dabc564990eeab55e25ed61c07a1aadafe9ece96a4efabb3f8bf9063b71ef",
+    "https://bcr.bazel.build/modules/stardoc/0.7.0/MODULE.bazel": "05e3d6d30c099b6770e97da986c53bd31844d7f13d41412480ea265ac9e8079c",
+    "https://bcr.bazel.build/modules/stardoc/0.7.1/MODULE.bazel": "3548faea4ee5dda5580f9af150e79d0f6aea934fc60c1cc50f4efdd9420759e7",
+    "https://bcr.bazel.build/modules/stardoc/0.7.1/source.json": "b6500ffcd7b48cd72c29bb67bcac781e12701cc0d6d55d266a652583cfcdab01",
+    "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.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": {
+    "@@rules_kotlin+//src/main/starlark/core/repositories:bzlmod_setup.bzl%rules_kotlin_extensions": {
+      "general": {
+        "bzlTransitiveDigest": "rL/34P1aFDq2GqVC2zCFgQ8nTuOC6ziogocpvG50Qz8=",
+        "usagesDigest": "QI2z8ZUR+mqtbwsf2fLqYdJAkPOHdOV+tF2yVAUgRzw=",
+        "recordedFileInputs": {},
+        "recordedDirentsInputs": {},
+        "envVariables": {},
+        "generatedRepoSpecs": {
+          "com_github_jetbrains_kotlin_git": {
+            "repoRuleId": "@@rules_kotlin+//src/main/starlark/core/repositories:compiler.bzl%kotlin_compiler_git_repository",
+            "attributes": {
+              "urls": [
+                "https://github.com/JetBrains/kotlin/releases/download/v1.9.23/kotlin-compiler-1.9.23.zip"
+              ],
+              "sha256": "93137d3aab9afa9b27cb06a824c2324195c6b6f6179d8a8653f440f5bd58be88"
+            }
+          },
+          "com_github_jetbrains_kotlin": {
+            "repoRuleId": "@@rules_kotlin+//src/main/starlark/core/repositories:compiler.bzl%kotlin_capabilities_repository",
+            "attributes": {
+              "git_repository_name": "com_github_jetbrains_kotlin_git",
+              "compiler_version": "1.9.23"
+            }
+          },
+          "com_github_google_ksp": {
+            "repoRuleId": "@@rules_kotlin+//src/main/starlark/core/repositories:ksp.bzl%ksp_compiler_plugin_repository",
+            "attributes": {
+              "urls": [
+                "https://github.com/google/ksp/releases/download/1.9.23-1.0.20/artifacts.zip"
+              ],
+              "sha256": "ee0618755913ef7fd6511288a232e8fad24838b9af6ea73972a76e81053c8c2d",
+              "strip_version": "1.9.23-1.0.20"
+            }
+          },
+          "com_github_pinterest_ktlint": {
+            "repoRuleId": "@@bazel_tools//tools/build_defs/repo:http.bzl%http_file",
+            "attributes": {
+              "sha256": "01b2e0ef893383a50dbeb13970fe7fa3be36ca3e83259e01649945b09d736985",
+              "urls": [
+                "https://github.com/pinterest/ktlint/releases/download/1.3.0/ktlint"
+              ],
+              "executable": true
+            }
+          },
+          "rules_android": {
+            "repoRuleId": "@@bazel_tools//tools/build_defs/repo:http.bzl%http_archive",
+            "attributes": {
+              "sha256": "cd06d15dd8bb59926e4d65f9003bfc20f9da4b2519985c27e190cddc8b7a7806",
+              "strip_prefix": "rules_android-0.1.1",
+              "urls": [
+                "https://github.com/bazelbuild/rules_android/archive/v0.1.1.zip"
+              ]
+            }
+          }
+        },
+        "recordedRepoMappingEntries": [
+          [
+            "rules_kotlin+",
+            "bazel_tools",
+            "bazel_tools"
+          ]
+        ]
+      }
+    }
+  },
+  "facts": {}
+}
diff --git a/nix/flake.lock b/nix/flake.lock
new file mode 100644
index 0000000..5fd6f52
--- /dev/null
+++ b/nix/flake.lock
@@ -0,0 +1,61 @@
+{
+  "nodes": {
+    "flake-utils": {
+      "inputs": {
+        "systems": "systems"
+      },
+      "locked": {
+        "lastModified": 1731533236,
+        "narHash": "sha256-l0KFg5HjrsfsO/JpG+r7fRrqm12kzFHyUHqHCVpMMbI=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "11707dc2f618dd54ca8739b309ec4fc024de578b",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1767379071,
+        "narHash": "sha256-EgE0pxsrW9jp9YFMkHL9JMXxcqi/OoumPJYwf+Okucw=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "fb7944c166a3b630f177938e478f0378e64ce108",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "flake-utils": "flake-utils",
+        "nixpkgs": "nixpkgs"
+      }
+    },
+    "systems": {
+      "locked": {
+        "lastModified": 1681028828,
+        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
+        "owner": "nix-systems",
+        "repo": "default",
+        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-systems",
+        "repo": "default",
+        "type": "github"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}
diff --git a/nix/flake.nix b/nix/flake.nix
new file mode 100644
index 0000000..240619c
--- /dev/null
+++ b/nix/flake.nix
@@ -0,0 +1,60 @@
+{
+  description = "pedagogical compiler monorepo (bazel + nix + clang + ccache)";
+
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
+    flake-utils.url = "github:numtide/flake-utils";
+  };
+
+  outputs =
+    {
+      self,
+      nixpkgs,
+      flake-utils,
+      ...
+    }:
+    flake-utils.lib.eachDefaultSystem (
+      system:
+      let
+        # pkgs = import nixpkgs { inherit system; config.replaceStdenv = {pkgs, ...}: pkgs.clangStdenv; };
+        pkgs = import nixpkgs { inherit system; };
+        # lock = builtins.fromJSON (builtins.readFile ./flake.lock);
+        # spec = lock.nodes.nixpkgs.locked;
+        # nixpkgs = fetchTarball "https://github.com/${spec.owner}/${spec.repo}/archive/${spec.rev}.tar.gz";
+      in
+      {
+        devShells.default = pkgs.mkShell {
+          name = "compiler stuff";
+          packages = with pkgs; [
+            # clang-tools
+            # bazelisk
+            bazel_8
+            bazel-buildtools
+            nix
+            git
+            gcc
+
+            doxygen
+            ccache
+            python3
+
+            ninja
+            clang-tools
+
+            z3
+            gtest
+            pkg-config
+            lit
+
+            buildifier
+            buildozer
+          ];
+          CC = "ccache clang";
+          CXX = "ccache clang++";
+          # LD_LIBRARY_PATH = nixpkgs.lib.makeLibraryPath [ pkgs.libcxx ];
+          NIX_HARDENING_ENABLE = "";
+        };
+      }
+    );
+}
+
diff --git a/willow/BUILD.bazel b/willow/BUILD.bazel
new file mode 100644
index 0000000..8726cbd
--- /dev/null
+++ b/willow/BUILD.bazel
@@ -0,0 +1,13 @@
+cc_library(
+    name = "willow",
+    srcs = [
+        "lib/IR/TypeContext.cpp",
+    ],
+    hdrs = glob([
+        "include/willow/**/*.h",
+    ]),
+    strip_include_prefix = "include",
+    visibility = ["//visibility:public"],
+    deps = [
+    ],
+)
diff --git a/willow/MODULE.bazel b/willow/MODULE.bazel
new file mode 100644
index 0000000..3597596
--- /dev/null
+++ b/willow/MODULE.bazel
@@ -0,0 +1,4 @@
+module(
+  name = "willow",
+  version = "0.0.1",
+)
diff --git a/willow/MODULE.bazel.lock b/willow/MODULE.bazel.lock
new file mode 100644
index 0000000..34d9edb
--- /dev/null
+++ b/willow/MODULE.bazel.lock
@@ -0,0 +1,139 @@
+{
+  "lockFileVersion": 18,
+  "registryFileHashes": {
+    "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",
+    "https://bcr.bazel.build/modules/abseil-cpp/20230125.1/MODULE.bazel": "89047429cb0207707b2dface14ba7f8df85273d484c2572755be4bab7ce9c3a0",
+    "https://bcr.bazel.build/modules/abseil-cpp/20230802.0.bcr.1/MODULE.bazel": "1c8cec495288dccd14fdae6e3f95f772c1c91857047a098fad772034264cc8cb",
+    "https://bcr.bazel.build/modules/abseil-cpp/20230802.0/MODULE.bazel": "d253ae36a8bd9ee3c5955384096ccb6baf16a1b1e93e858370da0a3b94f77c16",
+    "https://bcr.bazel.build/modules/abseil-cpp/20230802.1/MODULE.bazel": "fa92e2eb41a04df73cdabeec37107316f7e5272650f81d6cc096418fe647b915",
+    "https://bcr.bazel.build/modules/abseil-cpp/20240116.1/MODULE.bazel": "37bcdb4440fbb61df6a1c296ae01b327f19e9bb521f9b8e26ec854b6f97309ed",
+    "https://bcr.bazel.build/modules/abseil-cpp/20240116.1/source.json": "9be551b8d4e3ef76875c0d744b5d6a504a27e3ae67bc6b28f46415fd2d2957da",
+    "https://bcr.bazel.build/modules/bazel_features/1.1.1/MODULE.bazel": "27b8c79ef57efe08efccbd9dd6ef70d61b4798320b8d3c134fd571f78963dbcd",
+    "https://bcr.bazel.build/modules/bazel_features/1.11.0/MODULE.bazel": "f9382337dd5a474c3b7d334c2f83e50b6eaedc284253334cf823044a26de03e8",
+    "https://bcr.bazel.build/modules/bazel_features/1.15.0/MODULE.bazel": "d38ff6e517149dc509406aca0db3ad1efdd890a85e049585b7234d04238e2a4d",
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+    "https://bcr.bazel.build/modules/stardoc/0.7.1/MODULE.bazel": "3548faea4ee5dda5580f9af150e79d0f6aea934fc60c1cc50f4efdd9420759e7",
+    "https://bcr.bazel.build/modules/stardoc/0.7.1/source.json": "b6500ffcd7b48cd72c29bb67bcac781e12701cc0d6d55d266a652583cfcdab01",
+    "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.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": {}
+}
diff --git a/willow/docs/doxygen/Doxyfile b/willow/docs/doxygen/Doxyfile
new file mode 100644
index 0000000..bcb4641
--- /dev/null
+++ b/willow/docs/doxygen/Doxyfile
@@ -0,0 +1,10 @@
+PROJECT_NAME           = "Willow"
+OUTPUT_DIRECTORY       = "out/doxygen/willow"
+INPUT                  = willow/include
+RECURSIVE              = YES
+FILE_PATTERNS          = *.h
+GENERATE_HTML          = YES
+GENERATE_LATEX         = NO
+EXTRACT_ALL            = YES
+WARN_AS_ERROR          = YES
+QUIET                  = YES
diff --git a/willow/include/willow/IR/BasicBlock.h b/willow/include/willow/IR/BasicBlock.h
new file mode 100644
index 0000000..d783a5b
--- /dev/null
+++ b/willow/include/willow/IR/BasicBlock.h
@@ -0,0 +1,98 @@
+#ifndef WILLOW_IR_BASIC_BLOCK_H
+#define WILLOW_IR_BASIC_BLOCK_H
+
+#include <willow/IR/Instruction.h>
+
+#include <list>
+#include <memory>
+#include <ranges>
+#include <string>
+#include <string_view>
+#include <utility>
+#include <vector>
+
+namespace willow {
+
+class Function;
+
+/// A group of consecutive instructions.
+class BasicBlock {
+  std::string name;
+  Function *parent = nullptr;
+
+  std::list<std::unique_ptr<Instruction>> body;
+
+  std::vector<BasicBlock *> preds;
+  std::vector<BasicBlock *> succs;
+
+public:
+  // ~BasicBlock() = TODO
+  /// Create a basic block with a name and parent function.
+  BasicBlock(std::string name, Function *parent)
+      : name(std::move(name)), parent(parent) {}
+
+  std::string_view getName() const { return name; }
+  void setName(std::string name) { this->name = std::move(name); }
+
+  Function *getParent() const { return parent; }
+  bool hasParent() const { return parent; }
+  void setParent(Function *parent) { this->parent = parent; }
+
+  bool empty() const { return body.empty(); }
+  std::size_t size() { return body.size(); }
+
+  auto getBody() {
+    return body |
+           std::views::transform([](auto &p) -> Instruction & { return *p; });
+  }
+
+  auto getBody() const {
+    return body | std::views::transform(
+                      [](auto &p) -> const Instruction & { return *p; });
+  }
+
+  Instruction *trailer();
+  Instruction *leader();
+
+  Instruction *addInstruction(std::unique_ptr<Instruction> inst);
+
+  template <typename... Args>
+  Instruction *emplaceInstruction(Args &&...args) {
+    body.push_back(std::make_unique<Instruction>(std::forward(args)...));
+    return body.back().get();
+  }
+
+  const std::vector<BasicBlock *> &predecessors() const { return preds; }
+  std::vector<BasicBlock *> &predecessors() { return preds; }
+
+  const std::vector<BasicBlock *> &successors() const { return succs; }
+  std::vector<BasicBlock *> &successors() { return succs; }
+
+  void addPredecessor(BasicBlock *pred) { preds.push_back(pred); }
+  void addSuccessor(BasicBlock *succ) { succs.push_back(succ); }
+  // TODO: add/remove preds
+};
+
+Instruction *BasicBlock::trailer() {
+  if (empty())
+    return nullptr;
+  else
+    return body.back().get();
+}
+
+Instruction *BasicBlock::leader() {
+  if (empty())
+    return nullptr;
+  else
+    return body.back().get();
+}
+
+Instruction *BasicBlock::addInstruction(std::unique_ptr<Instruction> inst) {
+  Instruction *p = inst.get();
+  body.push_back(std::move(inst));
+  return p;
+}
+
+} // namespace willow
+
+#endif // WILLOW_IR_BASIC_BLOCK_H
diff --git a/willow/include/willow/IR/Function.h b/willow/include/willow/IR/Function.h
new file mode 100644
index 0000000..97e4029
--- /dev/null
+++ b/willow/include/willow/IR/Function.h
@@ -0,0 +1,104 @@
+#ifndef WILLOW_IR_FUNCTION_H
+#define WILLOW_IR_FUNCTION_H
+
+#include <willow/IR/BasicBlock.h>
+#include <willow/IR/Value.h>
+
+#include <memory>
+#include <ranges>
+#include <string>
+#include <string_view>
+#include <utility>
+#include <vector>
+
+namespace willow {
+
+class Module;
+
+/// Groups basic blocks and the values they define.
+class Function {
+  std::string name;
+  Module *parent = nullptr;
+
+  std::vector<std::unique_ptr<BasicBlock>> blocks;
+  std::vector<std::unique_ptr<Value>> values;
+
+public:
+  /// Create a function with a name and its owning module.
+  /// \param name Function identifier.
+  /// \param parent Owning module.
+  Function(std::string name, Module *parent)
+      : name(std::move(name)), parent(parent) {}
+
+  std::string_view getName() const { return name; }
+  void setName(std::string name) { this->name = std::move(name); }
+
+  /// \return Parent module or nullptr.
+  Module *getParent() { return parent; }
+  const Module *getParent() const { return parent; }
+  void setParent(Module *parent) { this->parent = parent; }
+
+  /// \return Entry block or nullptr.
+  BasicBlock *entryBlock();
+  const BasicBlock *entryBlock() const;
+
+  bool empty() const { return blocks.empty(); }
+  std::size_t numBlocks() const { return blocks.size(); }
+
+  /// \return The blocks that make up this function.
+  auto getBlocks() {
+    return blocks |
+           std::views::transform([](auto &p) -> BasicBlock & { return *p; });
+  }
+
+  auto getBlocks() const {
+    return blocks | std::views::transform(
+                        [](auto &p) -> const BasicBlock & { return *p; });
+  }
+
+  /// \return The SSA values that exist in this block.
+  auto getValues() {
+    return blocks |
+           std::views::transform([](auto &p) -> Value & { return *p; });
+  }
+  auto getValues() const {
+    return blocks |
+           std::views::transform([](auto &p) -> const Value & { return *p; });
+  }
+
+  /// Append an existing block, transferring ownership.
+  /// \param block Basic block to append.
+  /// \return Raw pointer to the appended block.
+  BasicBlock *addBlock(std::unique_ptr<BasicBlock> block) {
+    auto p = block.get();
+    blocks.push_back(std::move(block));
+    p->setParent(this);
+    return p;
+  }
+
+  /// Construct a new block in-place and append it.
+  /// \return Raw pointer to the appended block.
+  template <typename... Args>
+  BasicBlock *createBlock(Args &&...args) {
+    blocks.push_back(std::make_unique<BasicBlock>(std::forward<Args>(args)...));
+    return blocks.back().get();
+  }
+};
+
+const BasicBlock *Function::entryBlock() const {
+  if (blocks.empty())
+    return nullptr;
+  else
+    return blocks.front().get();
+}
+
+BasicBlock *Function::entryBlock() {
+  if (blocks.empty())
+    return nullptr;
+  else
+    return blocks.front().get();
+}
+
+} // namespace willow
+
+#endif // WILLOW_IR_FUNCTION_H
diff --git a/willow/include/willow/IR/IRBuilder.h b/willow/include/willow/IR/IRBuilder.h
new file mode 100644
index 0000000..79d3bb3
--- /dev/null
+++ b/willow/include/willow/IR/IRBuilder.h
@@ -0,0 +1,20 @@
+#ifndef WILLOW_IR_IR_BUILDER_H
+#define WILLOW_IR_IR_BUILDER_H
+
+#include <willow/IR/BasicBlock.h>
+#include <willow/IR/Function.h>
+#include <willow/IR/Instruction.h>
+
+namespace willow {
+
+/// Helper for constructing and modifiying IR.
+class IRBuilder {
+  BasicBlock *block = nullptr;
+
+public:
+  explicit IRBuilder(BasicBlock *block) : block(block);
+};
+
+} // namespace willow
+
+#endif // WILLOW_IR_IR_BUILDER_H
diff --git a/willow/include/willow/IR/Instruction.h b/willow/include/willow/IR/Instruction.h
new file mode 100644
index 0000000..c7756bb
--- /dev/null
+++ b/willow/include/willow/IR/Instruction.h
@@ -0,0 +1,61 @@
+#ifndef WILLOW_IR_INSTRUCTION_HPP
+#define WILLOW_IR_INSTRUCTION_HPP
+
+#include <willow/IR/Value.h>
+
+namespace willow {
+
+class Value;
+
+/// Defines an SSA value or control-flow effect.
+class Instruction : Value {
+public:
+  enum class Op {
+    Const,
+
+    Add,
+    Mul,
+    Sub,
+    Div,
+    Mod,
+    Shl,
+    Shr,
+
+    Eq,
+    Lt,
+    Gt,
+    Le,
+    Ge,
+
+    Not,
+    And,
+    Or,
+
+    Jmp,
+    Br,
+    Call,
+    Ret,
+
+    Phi,
+    Alloca
+  };
+
+private:
+  class BasicBlock *parent = nullptr;
+  Op op;
+
+public:
+  /// \param op Opcode for this instruction.
+  /// \param val SSA value defined by this instruction (may be nullptr).
+  Instruction(Op op, Value *val);
+
+  Op getOp() const { return op; }
+
+  const Value *getValue() const { return value; }
+  Value *getValue() { return value; }
+  bool hasValue() const { return value; }
+};
+
+} // namespace willow
+
+#endif // WILLOW_IR_INST_HPP
diff --git a/willow/include/willow/IR/Module.h b/willow/include/willow/IR/Module.h
new file mode 100644
index 0000000..2002a90
--- /dev/null
+++ b/willow/include/willow/IR/Module.h
@@ -0,0 +1,54 @@
+#ifndef WILLOW_IR_MODULE_H
+#define WILLOW_IR_MODULE_H
+
+#include <willow/IR/Function.h>
+
+namespace willow {
+
+/// Represents a compilation unit.
+class Module {
+  std::string name;
+  std::vector<std::unique_ptr<Function>> functions;
+
+public:
+  explicit Module(std::string name) : name(std::move(name)) {}
+
+  /// Moves a Function to this module, transfering ownership.
+  /// \param fn The function to move.
+  /// \return A raw pointer to the function.
+  Function *addFunction(std::unique_ptr<Function> fn);
+
+  template <typename... Args>
+  Function *emplaceFunction(Args &&...args) {
+    functions.push_back(
+        std::make_unique<Function>(std::forward<Args>(args)...));
+    auto *fn = functions.back().get();
+    fn->setParent(this);
+    return fn;
+  }
+
+  std::string_view getName() const { return name; }
+  void setName(std::string name) { this->name = std::move(name); }
+
+  std::size_t numFunctions() const { return functions.size(); }
+
+  auto getFunctions() {
+    return functions |
+           std::views::transform([](auto &p) -> Function & { return *p; });
+  }
+  auto getFunctions() const {
+    return functions | std::views::transform(
+                           [](auto &p) -> const Function & { return *p; });
+  }
+};
+
+Function *Module::addFunction(std::unique_ptr<Function> fn) {
+  auto p = fn.get();
+  functions.push_back(std::move(fn));
+  p->setParent(this);
+  return p;
+}
+
+} // namespace willow
+
+#endif // WILLOW_IR_MODULE_H
diff --git a/willow/include/willow/IR/TypeContext.h b/willow/include/willow/IR/TypeContext.h
new file mode 100644
index 0000000..d1323f0
--- /dev/null
+++ b/willow/include/willow/IR/TypeContext.h
@@ -0,0 +1,57 @@
+#ifndef _WILLOW_INCLUDE_TYPE_CONTEXT_H
+#define _WILLOW_INCLUDE_TYPE_CONTEXT_H
+
+#include <willow/IR/Types.h>
+
+#include <memory>
+#include <unordered_map>
+
+namespace willow {
+
+/// Context that owns and uniques type instances.
+class TypeContext {
+public:
+  TypeContext() = default;
+  TypeContext(const TypeContext &) = delete;
+  TypeContext &operator=(const TypeContext &) = delete;
+
+  /// \param width Bit width of the integer type.
+  /// \return Uniqued integer type for the requested width.
+  Type getIntType(std::size_t width);
+
+  /// \param pointee Type of the pointee.
+  /// \param size Size in bits of the pointer representation.
+  /// \return Uniqued pointer type.
+  Type getPtrType(Type pointee, std::size_t size);
+
+  /// \return Uniqued void type.
+  Type getVoidType();
+
+private:
+  std::unordered_map<IntTypeImpl::Key, std::unique_ptr<IntTypeImpl>,
+                     IntTypeImpl::Hash>
+      icache;
+  std::unordered_map<PtrTypeImpl::Key, std::unique_ptr<PtrTypeImpl>,
+                     PtrTypeImpl::Hash>
+      pcache;
+  std::unique_ptr<VoidTypeImpl> voidty;
+};
+
+Type TypeContext::getIntType(std::size_t width) {
+  auto [it, _] = icache.try_emplace(IntTypeImpl::Key{width});
+
+  return Type(it->second.get());
+}
+
+Type TypeContext::getPtrType(Type pointee, std::size_t size) {
+  auto [it, _] = pcache.try_emplace(
+      PtrTypeImpl::Key{pointee}, std::make_unique<PtrTypeImpl>(pointee, size));
+
+  return Type(it->second.get());
+}
+
+Type TypeContext::getVoidType() { return Type(voidty.get()); }
+
+} // namespace willow
+
+#endif // _WILLOW_INCLUDE_TYPE_CONTEXT_H
diff --git a/willow/include/willow/IR/Types.h b/willow/include/willow/IR/Types.h
new file mode 100644
index 0000000..85f4a67
--- /dev/null
+++ b/willow/include/willow/IR/Types.h
@@ -0,0 +1,108 @@
+#ifndef _WILLOW_IR_TYPES_H
+#define _WILLOW_IR_TYPES_H
+
+#include <cstddef>
+#include <functional>
+#include <ostream>
+
+namespace willow {
+
+/// IDs of all base types.
+enum class TypeID {
+  // Primitive types
+  Void,  ///< Void type
+  Label, ///< Label type
+
+  // Parameterized types
+  Int,      ///< Integer type of any bit width
+  Function, ///< A Function symbol
+  Ptr,      ///< Parameterized pointer type
+  Struct,   ///< Aggregate struct type
+  Vector,   ///< Vector type
+};
+
+class TypeImpl;
+
+class TypeImpl {
+  friend class TypeContext;
+  TypeID kind;
+  std::size_t num_bits;
+
+protected:
+  explicit TypeImpl(TypeID kind) : kind{kind} {}
+  explicit TypeImpl(TypeID kind, size_t num_bits)
+      : kind{kind}, num_bits{num_bits} {}
+
+public:
+  virtual ~TypeImpl() = default;
+  TypeID getTypeKind() const { return kind; }
+  std::size_t getNumBits() const { return num_bits; }
+};
+
+/// Instances of Type represent uniqued, immutable datatypes.
+///
+/// Internally, Type instances wrap a pointer to a TypeImpl, so they should be
+/// passed by value.
+class Type {
+  friend class TypeContext;
+  TypeImpl *impl;
+
+public:
+  explicit Type(TypeImpl *impl) : impl(impl) {}
+
+  bool operator==(const Type &other) const { return impl == other.impl; }
+  bool operator!=(const Type &other) const { return impl != other.impl; }
+  // Type() : impl(nullptr) {}
+
+  TypeID kind() const { return impl->getTypeKind(); };
+  std::size_t getNumBits() const { return impl->getNumBits(); };
+  TypeImpl *getImpl() const { return this->impl; }
+
+  bool isInt() const { return kind() == TypeID::Int; }
+  bool isPtr() const { return kind() == TypeID::Ptr; }
+  bool isVoid() const { return kind() == TypeID::Void; }
+};
+
+class IntTypeImpl : public TypeImpl {
+public:
+  explicit IntTypeImpl(std::size_t num_bits)
+      : TypeImpl{TypeID::Int, num_bits} {}
+
+  struct Key {
+    std::size_t num_bits;
+    Key(std::size_t w) : num_bits(w) {}
+
+    bool operator==(const Key &k) const { return this->num_bits == k.num_bits; }
+  };
+
+  struct Hash {
+    std::size_t operator()(const Key &k) const noexcept {
+      return std::hash<size_t>{}(k.num_bits);
+    }
+  };
+};
+
+class PtrTypeImpl : public TypeImpl {
+  Type pointee;
+
+public:
+  PtrTypeImpl(Type pointee_type, std::size_t size)
+      : TypeImpl{TypeID::Ptr, size}, pointee{pointee_type.getImpl()} {}
+
+  struct Key {
+    Type pointee;
+    explicit Key(Type pointee) : pointee{pointee} {}
+
+    bool operator==(const Key &k) const { return this->pointee == k.pointee; }
+  };
+
+  struct Hash {
+    std::size_t operator()(const Key &k) const noexcept {
+      return std::hash<TypeImpl *>{}(k.pointee.getImpl());
+    }
+  };
+};
+
+}; // namespace willow
+
+#endif // _WILLOW_IR_TYPES_H
diff --git a/willow/include/willow/IR/Value.h b/willow/include/willow/IR/Value.h
new file mode 100644
index 0000000..a819b53
--- /dev/null
+++ b/willow/include/willow/IR/Value.h
@@ -0,0 +1,50 @@
+#ifndef _WILLOW_IR_VALUE_HPP
+#define _WILLOW_IR_VALUE_HPP
+
+// #include <willow/IR/Instruction.h>
+#include <willow/IR/Types.h>
+
+#include <string>
+#include <string_view>
+#include <vector>
+
+namespace willow {
+
+class Instruction;
+
+enum class ValueType {
+  Result,    ///< the identified result of an instruction
+  Parameter, ///< the named parameter to a function
+  Literal,   ///< an anonymous typed literal
+};
+
+/// An SSA value that may be used.
+class Value {
+  std::string name;
+  ValueType value_type;
+  Type type;
+
+  // Instructions that use this value
+  std::vector<Instruction *> uses;
+
+public:
+  Value(std::string name, Type type) : name(std::move(name)), type(type) {}
+  explicit Value(Type type) : type(type) {}
+
+  bool hasName() const { return !name.empty(); }
+
+  std::string_view getName() const { return name; }
+  void setName(std::string name) { this->name = std::move(name); }
+
+  Type getType() const { return type; }
+  ValueType getValueType() const { return value_type; }
+
+  bool isVoid() const { return type->is }
+
+  const std::vector<Instruction *> &getUses() const { return uses; }
+  std::vector<Instruction *> &getUses() { return uses; }
+};
+
+} // namespace willow
+
+#endif // _WILLOW_IR_VALUE_HPP
diff --git a/willow/lib/IR/TypeContext.cpp b/willow/lib/IR/TypeContext.cpp
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/willow/lib/IR/TypeContext.cpp
author	Stefan Weigl-Bosker <stefan@s00.xyz>	2026-01-05 12:40:09 -0500
committer	Stefan Weigl-Bosker <stefan@s00.xyz>	2026-01-10 15:37:46 -0500
commit	d4b629cc275769c2553db819643849cda2395a17 (patch)
tree	6dcc5d0c886945f8b58b4d8fd6c7eea4bb1b194d
download	compiler-d4b629cc275769c2553db819643849cda2395a17.tar.gz