.bazelversion

-last_rc
-# TODO: relax this once we have `use_rule_repo`
+7.0.0rc7
\ No newline at end of file

.npmrc

+registry=https://gitlab.arm.com/api/v4/groups/semantic-release/-/packages/npm/

.reuse/dep5

@@ -15,6 +15,7 @@ Copyright: 2023 Arm Ltd.
 License: MIT
 
 Files:
+  .npmrc
   icon.svg
   package.json
   package-lock.json

CHANGELOG.md

+# [1.0.0-alpha.7](https://git.gitlab.arm.com/bazel/rules_toolchain/compare/v1.0.0-alpha.6...v1.0.0-alpha.7) (2023-12-08)
+
+### Bug Fixes
+
+- be graceful when `uname` is not found ([6f4242c](https://git.gitlab.arm.com/bazel/rules_toolchain/commit/6f4242c19284b424ffd4079c0a02ed6a2bdef103))
+- correct `{{basename}}` in `which` ([892c623](https://git.gitlab.arm.com/bazel/rules_toolchain/commit/892c6233cce27d1ff2a6b950d3ddca1e34b807ff))
+- fail fast when not three Linux version parts ([e298c3e](https://git.gitlab.arm.com/bazel/rules_toolchain/commit/e298c3e5e0674809bd62def624aaf0104089468e))
+- need to foward on `.cmd` not `.com` ([49d7c9f](https://git.gitlab.arm.com/bazel/rules_toolchain/commit/49d7c9fd03763b135cf2e19db16ddfe30e00c8a5))
+- pin Bazel version ([585e5f4](https://git.gitlab.arm.com/bazel/rules_toolchain/commit/585e5f4168736c050687be6e59c359ab3a50f8ae))
+- **resolved:** propagate `.bat`/`.com` extensions ([b0a4176](https://git.gitlab.arm.com/bazel/rules_toolchain/commit/b0a4176194fcf379e4ab4a8ac9f213f34bc9771c))
+- **select:** add `map` to the error string ([727be3b](https://git.gitlab.arm.com/bazel/rules_toolchain/commit/727be3b7570aebda46b78560cd98cbaa74368b99))
+- **symlink_target:** propagate `.bat`/`.com` extensions ([78a6265](https://git.gitlab.arm.com/bazel/rules_toolchain/commit/78a62657e5dc911a75418afb28243e0d29f3db93))
+- **symlink_target:** use `ctx.executable` ([fdf8d73](https://git.gitlab.arm.com/bazel/rules_toolchain/commit/fdf8d732de0a1137172d0cbd311277834760dbe8))
+- **test:** simplify POSIX variable substitution ([82a4eca](https://git.gitlab.arm.com/bazel/rules_toolchain/commit/82a4ecaa71dbd06c98f24ef5fb4dc40ad58a40a6))
+
+### Features
+
+- add `//toolchain/constraint/libc:ucrt` ([4deb57e](https://git.gitlab.arm.com/bazel/rules_toolchain/commit/4deb57e881ad3fd4e43b49bc5a6724ad0db68ffd))
+- add `//toolchain/constraint/os:windows` ([064ecaf](https://git.gitlab.arm.com/bazel/rules_toolchain/commit/064ecafcc9b0a1ed3afc3c62c459f0b541438b27))
+- add a plain string value to local triplet repository ([e41e05f](https://git.gitlab.arm.com/bazel/rules_toolchain/commit/e41e05ffec1208b535ccfdcb4d70bc5d4c9311af))
+- add launcher ([96823ab](https://git.gitlab.arm.com/bazel/rules_toolchain/commit/96823abd1096cb17d81b554072916450f6944fa7))
+- add simple Windows OS detection ([a090eab](https://git.gitlab.arm.com/bazel/rules_toolchain/commit/a090eabe2dae4e52eb611c610c617437a31a46f0))
+- add Universal C runtime detection ([cd8b097](https://git.gitlab.arm.com/bazel/rules_toolchain/commit/cd8b097bd731403b3502214fffefb15089a975be))
+- add Windows version detection ([b2d0c53](https://git.gitlab.arm.com/bazel/rules_toolchain/commit/b2d0c53752ca2488a7ae9c70697591098bdb06b3))
+- **local/which:** support Windows ([1398d38](https://git.gitlab.arm.com/bazel/rules_toolchain/commit/1398d3869c59f6500def3894c4065ef2d9a0d9a1))
+- **select:** add more selection options ([22e5104](https://git.gitlab.arm.com/bazel/rules_toolchain/commit/22e5104a50b8fcfdffed77a2c8af82bdb79c512f))
+- **test:** add Batch script for Windows ([ea1a75d](https://git.gitlab.arm.com/bazel/rules_toolchain/commit/ea1a75db5b906e31646d0e41adad7b8ad8a63381))
+- **toolchain_triplet:** add Windows support ([32e2220](https://git.gitlab.arm.com/bazel/rules_toolchain/commit/32e2220df6254455713d331f9cbd4509fb9d9bc8))
+
 # [1.0.0-alpha.6](https://git.gitlab.arm.com/bazel/rules_toolchain/compare/v1.0.0-alpha.5...v1.0.0-alpha.6) (2023-11-30)
 
 ### Bug Fixes

MODULE.bazel

 module(
     name = "rules_toolchain",
-    version = "1.0.0-alpha.6",
+    version = "1.0.0-alpha.7",
     bazel_compatibility = [
         ">=6.4.0",
     ],
+    compatibility_level = 1,
 )
 
 bazel_dep(name = "bazel_skylib", version = "1.4.2")
 bazel_dep(name = "platforms", version = "0.0.7")
 
-triplet = use_repo_rule("//toolchain/local/triplet:repository.bzl", "triplet")
+triplet = use_repo_rule("//toolchain/local/triplet:defs.bzl", "toolchain_local_triplet")
 
 triplet(
     name = "local",
 )
+
+launcher = use_repo_rule("//toolchain/launcher:repository.bzl", "launcher")
+
+launcher(
+    name = "launcher",
+)

MODULE.bazel.lock

 {
   "lockFileVersion": 3,
-  "moduleFileHash": "40376b7f2b286e2b47922cf35c49ab73256806d8f016a140a6e0ca8e3fe94475",
+  "moduleFileHash": "55a8f1e3f74b9d8c0339def09fee2ef9e3ba7d6867977992475a8ff11094305f",
   "flags": {
     "cmdRegistries": [
       "https://bcr.bazel.build/"
@@ -34,12 +34,13 @@
             "column": 0
           },
           "imports": {
-            "local": "local"
+            "local": "local",
+            "launcher": "launcher"
           },
           "devImports": [],
           "tags": [
             {
-              "tagName": "//toolchain/local/triplet:repository.bzl%triplet",
+              "tagName": "//toolchain/local/triplet:defs.bzl%toolchain_local_triplet",
               "attributeValues": {
                 "name": "local"
               },
@@ -49,6 +50,18 @@
                 "line": 14,
                 "column": 8
               }
+            },
+            {
+              "tagName": "//toolchain/launcher:repository.bzl%launcher",
+              "attributeValues": {
+                "name": "launcher"
+              },
+              "devDependency": false,
+              "location": {
+                "file": "@@//:MODULE.bazel",
+                "line": 20,
+                "column": 9
+              }
             }
           ],
           "hasDevUseExtension": false,
@@ -656,7 +669,7 @@
   "moduleExtensions": {
     "//:MODULE.bazel%_repo_rules": {
       "general": {
-        "bzlTransitiveDigest": "VGGV2/aS8KP0wlEaxXfdomUzHtZ4Ry+aV/L2Ktp3UCo=",
+        "bzlTransitiveDigest": "CSJxsw5u8tv972NPHJazAfB/a3Rb8wU8pXWhqZJv+Wk=",
         "accumulatedFileDigests": {},
         "envVariables": {},
         "generatedRepoSpecs": {
@@ -666,6 +679,13 @@
             "attributes": {
               "name": "_main~_repo_rules~local"
             }
+          },
+          "launcher": {
+            "bzlFile": "@@//toolchain/launcher:repository.bzl",
+            "ruleClassName": "launcher",
+            "attributes": {
+              "name": "_main~_repo_rules~launcher"
+            }
           }
         }
       }

README.md

@@ -4,45 +4,20 @@
 
 ## Getting Started
 
-### Local Tool
-
 Add the following to `MODULE.bazel`:
 
 ```py
-which = use_repo_rule("@rules_toolchain//toolchain:defs.bzl", "toolchain_local_which")
+which = use_repo_rule("@rules_toolchain//toolchain/local/which:defs.bzl", "toolchain_local_which")
 which(
     name = "echo",
     toolchain_type = "//toolchain/echo:type",
 )
 ```
 
-The `echo` tool will be found on the `PATH`.
-
-A repository with the `@echo//:echo` target will be created.
-
-### Downloaded Tool
-
-Use `rules_download` to provide a hermetic, pre-built binary in `MODULE.bazel`
-
-```py
-archive = use_repo_rule("@rules_download//download:defs.bzl", "download_archive")
-archive(
-    name = "coreutils-arm64-linux-gnu",
-    srcs = ["coreutils"],
-    integrity = "sha256-mlmkbeabyu4+5+cFiUSL6Ki4KFNqWu48gTjFc3NS43g=",
-    strip_prefix = "coreutils-0.0.21-aarch64-unknown-linux-gnu",
-    urls = ["https://github.com/uutils/coreutils/releases/download/0.0.21/coreutils-0.0.21-aarch64-unknown-linux-gnu.tar.gz"],
-)
-```
-
-A repository with the `@coreutils-arm64-linux-gnu//:coreutils` target will be created.
-
-### Toolchains
-
 Create a `toolchain/echo/BUILD.bazel` with the following:
 
 ```py
-load("@rules_toolchain//toolchain:defs.bzl", "toolchain_symlink_target", "toolchain_test")
+load("@rules_toolchain//toolchain/test:defs.bzl", "toolchain_test")
 
 # The `toolchain/echo:type` for registration
 toolchain_type(
@@ -54,29 +29,55 @@ toolchain_type(
 # No `exec_compatible_with` constraints are needed as a local binary is always compatible with the execution platform
 toolchain(
     name = "local",
-    toolchain = "@echo",
+    toolchain = "@echo//:echo",
     toolchain_type = ":type",
 )
 
-# Create a toolchain binary from the downloaded `coreutils`
-toolchain_symlink_target(
-    name = "coreutils-arm64-linux-gnu",
-    target = "@coreutils-arm64-linux-gnu//:coreutils",
+# Run the resolved toolchain with:
+#   bazel run -- //toolchain/echo:resolved
+alias(
+    name = "resolved",
+    actual = "@echo//:resolved",
 )
 
-# Create a symlink to the multi-call binary
+# Performs a execution test of the binary
+# Validates it works on the current platform
+toolchain_test(
+    name = "test",
+    args = ["Hello, world!"],
+    stdout = ":hello-world.txt",
+    toolchains = [":resolved"],
+)
+```
+
+To create a hermetic toolchain from a built target:
+
+```py
+load("@rules_toolchain//toolchain/symlink/target:defs.bzl", "toolchain_symlink_target")
+
+# Assumes that `:echo` points to a Bazel built `echo` binary
 toolchain_symlink_target(
-    name = "echo-arm64-linux-gnu",
-    basename = "echo",
-    target = ":coreutils-arm64-linux-gnu",
+    name = "built",
+    target = ":echo"
 )
 
 # Register the hermetic toolchain
-# Use constraints to signify what host machines the toolchain is compatible with
+toolchain(
+    name = "hermetic",
+    toolchain = ":built",
+    toolchain_type = ":type",
+)
+```
+
+To create a hermetic toolchain from a downloaded target:
+
+```py
+# Assume `:echo-arm64-linux-gnu` is a downloaded `echo` binary
 toolchain(
     name = "arm64-linux",
     toolchain = ":echo-arm64-linux-gnu",
     toolchain_type = ":type",
+    # Use constraints to signify what host machines the toolchain is compatible with
     exec_compatible_with = [
         "@rules_toolchain//toolchain/constraint/cpu:arm64",
         "@rules_toolchain//toolchain/constraint/os:linux",
@@ -84,23 +85,6 @@ toolchain(
         # "@rules_toolchain//toolchain/constraint/libc:gnu",
     ],
 )
-
-# Provide a resolved toolchain target
-alias(
-    name = "resolved",
-    actual = "@echo//:resolved",
-)
 ```
 
-### Run
-
-The `resolved` target allows the toolchain that is compatible with the current machine to be executed:
-
-```py
-bazelisk run -- //toolchain/echo:resolved "Hello, world!"
-```
-
-If the machine is compatible with the downloaded toolchain constraints, that will be used. Otherwise, it will fallback
-to finding the toolchain on the local `PATH`.
-
 [resolved]: https://github.com/bazelbuild/bazel/issues/14009

e2e/.bazelversion

-last_rc
-# TODO: relax this once we have `use_rule_repo`
+7.0.0rc7
\ No newline at end of file

e2e/MODULE.bazel

@@ -12,14 +12,14 @@ local_path_override(
     path = "..",
 )
 
-which = use_repo_rule("@rules_toolchain//toolchain:defs.bzl", "toolchain_local_which")
+which = use_repo_rule("@rules_toolchain//toolchain/local/which:defs.bzl", "toolchain_local_which")
 
 which(
     name = "echo",
     toolchain_type = "//toolchain/echo:type",
 )
 
-resolved = use_repo_rule("@rules_toolchain//toolchain:defs.bzl", "toolchain_resolved")
+resolved = use_repo_rule("@rules_toolchain//toolchain/resolved:defs.bzl", "toolchain_resolved")
 
 resolved(
     name = "resolved",
@@ -42,7 +42,15 @@ fixture(
     name = "fixture-arm-linux-musl",
 )
 
-select = use_repo_rule("@rules_toolchain//toolchain:defs.bzl", "toolchain_local_select")
+fixture(
+    name = "fixture-windows-ucrt",
+)
+
+fixture(
+    name = "fixture-arm64-windows-ucrt",
+)
+
+select = use_repo_rule("@rules_toolchain//toolchain/local/select:defs.bzl", "toolchain_local_select")
 
 select(
     name = "fixture",
@@ -50,6 +58,7 @@ select(
         "amd64-linux-gnu": "@fixture-amd64-linux-gnu",
         "arm64-linux-gnu": "@fixture-arm64-linux-gnu",
         "arm-linux-musl": "@fixture-arm-linux-musl",
+        "windows-ucrt": "@fixture-windows-ucrt",
     },
 )
 

e2e/MODULE.bazel.lock

 {
   "lockFileVersion": 3,
-  "moduleFileHash": "7c7e76923d2e2442dc1fbaa7b1e37fda17ab54a2eefba7b32eab54747d049bc9",
+  "moduleFileHash": "33d7bab2dd31ed91bc652763be07b5096e6999fccdf0ed68bad1008aa7b9884c",
   "flags": {
     "cmdRegistries": [
       "https://bcr.bazel.build/"
@@ -13,7 +13,7 @@
     "compatibilityMode": "ERROR"
   },
   "localOverrideHashes": {
-    "rules_toolchain": "40376b7f2b286e2b47922cf35c49ab73256806d8f016a140a6e0ca8e3fe94475",
+    "rules_toolchain": "55a8f1e3f74b9d8c0339def09fee2ef9e3ba7d6867977992475a8ff11094305f",
     "bazel_tools": "922ea6752dc9105de5af957f7a99a6933c0a6a712d23df6aad16a9c399f7e787"
   },
   "moduleDepGraph": {
@@ -42,12 +42,14 @@
             "fixture-amd64-linux-gnu": "fixture-amd64-linux-gnu",
             "fixture-arm64-linux-gnu": "fixture-arm64-linux-gnu",
             "fixture-arm-linux-musl": "fixture-arm-linux-musl",
+            "fixture-windows-ucrt": "fixture-windows-ucrt",
+            "fixture-arm64-windows-ucrt": "fixture-arm64-windows-ucrt",
             "fixture": "fixture"
           },
           "devImports": [],
           "tags": [
             {
-              "tagName": "@rules_toolchain//toolchain:defs.bzl%toolchain_local_which",
+              "tagName": "@rules_toolchain//toolchain/local/which:defs.bzl%toolchain_local_which",
               "attributeValues": {
                 "toolchain_type": "//toolchain/echo:type",
                 "name": "echo"
@@ -60,7 +62,7 @@
               }
             },
             {
-              "tagName": "@rules_toolchain//toolchain:defs.bzl%toolchain_resolved",
+              "tagName": "@rules_toolchain//toolchain/resolved:defs.bzl%toolchain_resolved",
               "attributeValues": {
                 "toolchain_type": "//toolchain/echo:type",
                 "name": "resolved"
@@ -109,19 +111,44 @@
               }
             },
             {
-              "tagName": "@rules_toolchain//toolchain:defs.bzl%toolchain_local_select",
+              "tagName": "//test/fixture:repository.bzl%fixture",
+              "attributeValues": {
+                "name": "fixture-windows-ucrt"
+              },
+              "devDependency": false,
+              "location": {
+                "file": "@@//:MODULE.bazel",
+                "line": 45,
+                "column": 8
+              }
+            },
+            {
+              "tagName": "//test/fixture:repository.bzl%fixture",
+              "attributeValues": {
+                "name": "fixture-arm64-windows-ucrt"
+              },
+              "devDependency": false,
+              "location": {
+                "file": "@@//:MODULE.bazel",
+                "line": 49,
+                "column": 8
+              }
+            },
+            {
+              "tagName": "@rules_toolchain//toolchain/local/select:defs.bzl%toolchain_local_select",
               "attributeValues": {
                 "map": {
                   "amd64-linux-gnu": "@fixture-amd64-linux-gnu",
                   "arm64-linux-gnu": "@fixture-arm64-linux-gnu",
-                  "arm-linux-musl": "@fixture-arm-linux-musl"
+                  "arm-linux-musl": "@fixture-arm-linux-musl",
+                  "windows-ucrt": "@fixture-windows-ucrt"
                 },
                 "name": "fixture"
               },
               "devDependency": false,
               "location": {
                 "file": "@@//:MODULE.bazel",
-                "line": 47,
+                "line": 55,
                 "column": 7
               }
             }
@@ -135,7 +162,7 @@
           "usingModule": "<root>",
           "location": {
             "file": "@@//:MODULE.bazel",
-            "line": 56,
+            "line": 65,
             "column": 23
           },
           "imports": {
@@ -152,7 +179,7 @@
               "devDependency": false,
               "location": {
                 "file": "@@//:MODULE.bazel",
-                "line": 57,
+                "line": 66,
                 "column": 15
               }
             }
@@ -217,12 +244,13 @@
             "column": 0
           },
           "imports": {
-            "local": "local"
+            "local": "local",
+            "launcher": "launcher"
           },
           "devImports": [],
           "tags": [
             {
-              "tagName": "//toolchain/local/triplet:repository.bzl%triplet",
+              "tagName": "//toolchain/local/triplet:defs.bzl%toolchain_local_triplet",
               "attributeValues": {
                 "name": "local"
               },
@@ -232,6 +260,18 @@
                 "line": 14,
                 "column": 8
               }
+            },
+            {
+              "tagName": "//toolchain/launcher:repository.bzl%launcher",
+              "attributeValues": {
+                "name": "launcher"
+              },
+              "devDependency": false,
+              "location": {
+                "file": "@@rules_toolchain~override//:MODULE.bazel",
+                "line": 20,
+                "column": 9
+              }
             }
           ],
           "hasDevUseExtension": false,
@@ -808,7 +848,7 @@
   "moduleExtensions": {
     "//:MODULE.bazel%_repo_rules": {
       "general": {
-        "bzlTransitiveDigest": "/R69egUTLvkHkALvRLGxIJMgJWsQ0N6s2oGkMp4YL30=",
+        "bzlTransitiveDigest": "H6a/EFhNB57YKE/R9dWOnzyt7/yZUN4dwbh4eVfSEko=",
         "accumulatedFileDigests": {},
         "envVariables": {},
         "generatedRepoSpecs": {
@@ -849,6 +889,20 @@
               "name": "_main~_repo_rules~fixture-arm-linux-musl"
             }
           },
+          "fixture-windows-ucrt": {
+            "bzlFile": "@@//test/fixture:repository.bzl",
+            "ruleClassName": "fixture",
+            "attributes": {
+              "name": "_main~_repo_rules~fixture-windows-ucrt"
+            }
+          },
+          "fixture-arm64-windows-ucrt": {
+            "bzlFile": "@@//test/fixture:repository.bzl",
+            "ruleClassName": "fixture",
+            "attributes": {
+              "name": "_main~_repo_rules~fixture-arm64-windows-ucrt"
+            }
+          },
           "fixture": {
             "bzlFile": "@@rules_toolchain~override//toolchain/local/select:repository.bzl",
             "ruleClassName": "select",
@@ -856,7 +910,8 @@
               "map": {
                 "amd64-linux-gnu": "@fixture-amd64-linux-gnu",
                 "arm64-linux-gnu": "@fixture-arm64-linux-gnu",
-                "arm-linux-musl": "@fixture-arm-linux-musl"
+                "arm-linux-musl": "@fixture-arm-linux-musl",
+                "windows-ucrt": "@fixture-windows-ucrt"
               },
               "name": "_main~_repo_rules~fixture"
             }
@@ -1468,7 +1523,7 @@
     },
     "@@rules_toolchain~override//:MODULE.bazel%_repo_rules": {
       "general": {
-        "bzlTransitiveDigest": "VGGV2/aS8KP0wlEaxXfdomUzHtZ4Ry+aV/L2Ktp3UCo=",
+        "bzlTransitiveDigest": "CSJxsw5u8tv972NPHJazAfB/a3Rb8wU8pXWhqZJv+Wk=",
         "accumulatedFileDigests": {},
         "envVariables": {},
         "generatedRepoSpecs": {
@@ -1478,13 +1533,20 @@
             "attributes": {
               "name": "rules_toolchain~override~_repo_rules~local"
             }
+          },
+          "launcher": {
+            "bzlFile": "@@rules_toolchain~override//toolchain/launcher:repository.bzl",
+            "ruleClassName": "launcher",
+            "attributes": {
+              "name": "rules_toolchain~override~_repo_rules~launcher"
+            }
           }
         }
       }
     },
     "@@rules_toolchain~override//toolchain/export:defs.bzl%toolchain_export": {
       "general": {
-        "bzlTransitiveDigest": "GaX6IuOvOKsD8efBm9Fy5gFKF6piHEW7gvUENxCsD9M=",
+        "bzlTransitiveDigest": "BzNop8Xd2QfFtwy+F4thyq9O+CpaFjHeMWKDF15GMaM=",
         "accumulatedFileDigests": {},
         "envVariables": {},
         "generatedRepoSpecs": {

e2e/toolchain/echo/BUILD.bazel

-load("@rules_toolchain//toolchain:defs.bzl", "toolchain_symlink_target", "toolchain_test")
+load("@rules_toolchain//toolchain/symlink/target:defs.bzl", "toolchain_symlink_target")
+load("@rules_toolchain//toolchain/test:defs.bzl", "toolchain_test")
 load("@bazel_skylib//rules:build_test.bzl", "build_test")
 
 toolchain_type(
@@ -6,20 +7,24 @@ toolchain_type(
     visibility = ["//visibility:public"],
 )
 
-toolchain_symlink_target(
-    name = "hermetic",
-    target = ":echo.sh",
-)
-
 toolchain(
     name = "local",
     toolchain = "@echo//:echo",
     toolchain_type = ":type",
 )
 
-alias(
-    name = "echo",
-    actual = "hermetic",
+toolchain_symlink_target(
+    name = "script",
+    target = select({
+        "@rules_toolchain//toolchain/constraint/os:windows": ":echo.bat",
+        "//conditions:default": ":echo.sh",
+    }),
+)
+
+toolchain(
+    name = "hermetic",
+    toolchain = ":script",
+    toolchain_type = ":type",
 )
 
 alias(

e2e/toolchain/echo/echo.bat

+@echo.%*
\ No newline at end of file

package.json

@@ -2,11 +2,11 @@
   "private": true,
   "devDependencies": {
     "@bazel/bazelisk": "^1",
-    "@semantic-release/bzlmod": "https://gitlab.arm.com/semantic-release/bzlmod/-/releases/v1.1.0/downloads/package.tar.gz",
+    "@semantic-release/bzlmod": "^1",
     "@semantic-release/changelog": "^6",
     "@semantic-release/commit-analyzer": "^11",
-    "@semantic-release/config-gitlab-bzlmod": "https://gitlab.arm.com/semantic-release/config-gitlab-bzlmod/-/releases/v1.1.3/downloads/package.tar.gz",
-    "@semantic-release/config-release-channels": "https://gitlab.arm.com/semantic-release/config-release-channels/-/releases/v1.0.1/downloads/package.tar.gz",
+    "@semantic-release/config-gitlab-bzlmod": "^1",
+    "@semantic-release/config-release-channels": "^1",
     "@semantic-release/error": "^4",
     "@semantic-release/exec": "^6",
     "@semantic-release/git": "^10",

toolchain/constraint/libc/BUILD.bazel

@@ -6,3 +6,8 @@ constraint_value(
     name = "gnu",
     constraint_setting = ":libc",
 )
+
+constraint_value(
+    name = "ucrt",
+    constraint_setting = ":libc",
+)

toolchain/constraint/libc/ucrt/BUILD.bazel

+load(":versions.bzl", "VERSIONS")
+
+package(default_visibility = ["//visibility:public"])
+
+constraint_setting(name = "ucrt")
+
+[
+    constraint_value(
+        name = version,
+        constraint_setting = ":ucrt",
+    )
+    for version in VERSIONS
+]

toolchain/constraint/libc/ucrt/versions.bzl

+load("@local//:triplet.bzl", "TRIPLET")
+
+visibility("//toolchain/...")
+
+LOCAL = TRIPLET.libc.version and TRIPLET.libc.version.value
+
+# TODO: figure out a way to generate Universal CRT versions
+
+VERSIONS = tuple([LOCAL] if LOCAL != None else [])

toolchain/constraint/os/BUILD.bazel

 package(default_visibility = ["//visibility:public"])
 
-# TODO: add more OS aliases when we are ready to support them.
-[
-    alias(
-        name = v,
-        actual = "@platforms//os:{}".format(v),
-    )
-    for v in (
-        "linux",
-    )
-]
+alias(
+    name = "linux",
+    actual = "@platforms//os:linux",
+)
+
+alias(
+    name = "windows",
+    actual = "@platforms//os:windows",
+)

toolchain/constraint/os/windows/BUILD.bazel

+load(":versions.bzl", "VERSIONS")
+
+package(default_visibility = ["//visibility:public"])
+
+constraint_setting(name = "windows")
+
+[
+    constraint_value(
+        name = version,
+        constraint_setting = ":windows",
+    )
+    for version in VERSIONS
+]

toolchain/constraint/os/windows/versions.bzl

+load("@local//:triplet.bzl", "TRIPLET")
+
+visibility("//toolchain/...")
+
+LOCAL = TRIPLET.os.version and TRIPLET.os.version.value
+
+# TODO: figure out a way to generate Windows versions
+
+VERSIONS = tuple([LOCAL] if LOCAL != None else [])