feat: add native Windows runtime, stdlib arms, and CI lanes

.github/workflows/ci.yml

@@ -74,26 +74,34 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-latest, macos-latest]
+        os: [ubuntu-latest, macos-latest, windows-latest]
     # Bundled regrtests are required to pass (see RFC 0026). The
     # runner gates on `tests/regrtest/expectations.toml` by default, so
     # any divergence — pass → fail, fail → pass — fails the job. Pull
     # requests update both the test and the baseline in the same
     # commit.
+    #
+    # The windows leg is advisory via the baseline's `measured_os`
+    # stamp (RFC 0063 WS7), not via CI config: the runner prints the
+    # full report, uploads the measured artifact below, and exits 0 on
+    # unexpected results until a measured Windows baseline is
+    # transplanted and "windows" joins the stamp.
     steps:
       - uses: actions/checkout@v4
       - uses: dtolnay/rust-toolchain@stable
       - uses: Swatinem/rust-cache@v2
       - name: Build weavepy CLI
         run: cargo build --release -p weavepy-cli
       - name: Run bundled regrtests (subprocess, parallel)
+        shell: bash
         run: |
           cargo run --release -p weavepy-cli -- regrtest \
             --mode subprocess \
             --workers 4 \
             --timeout 60
       - name: Append regrtest report to job summary
         if: always()
+        shell: bash
         run: |
           {
             echo "## WeavePy regrtest"
@@ -113,7 +121,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-latest, macos-latest]
+        os: [ubuntu-latest, macos-latest, windows-latest]
     # RFC 0058 — the benchmark lane. Gates on WeavePy/CPython *ratios*
     # against the per-platform baselines/bench-{os}-{arch}.json (RFC
     # 0062 WS3; host-independent, unlike absolute times); the 25%
@@ -129,18 +137,21 @@ jobs:
       - name: Build weavepy CLI + bench harness
         run: cargo build --release -p weavepy-cli -p weavepy-bench
       - name: Run bench gate
-        # Linux has no committed per-platform baseline yet, so the gate
-        # is advisory there (--allow-missing-baseline prints a note and
-        # exits 0). It graduates to strict once a measured
-        # bench-linux-x86_64.json is committed — drop the flag then.
-        # macOS gates strictly against bench-macos-aarch64.json.
+        # Linux and Windows have no committed per-platform baseline
+        # yet, so the gate is advisory there (--allow-missing-baseline
+        # prints a note and exits 0). Each leg graduates to strict once
+        # its measured bench-{os}-x86_64.json is committed — drop the
+        # flag for that OS then (RFC 0062 for linux, RFC 0063 for
+        # windows). macOS gates strictly against bench-macos-aarch64.json.
+        shell: bash
         run: |
           target/release/weavepy-bench gate --pct=25 \
             --weavepy=target/release/weavepy \
-            ${{ matrix.os == 'ubuntu-latest' && '--allow-missing-baseline' || '' }} \
+            ${{ (matrix.os == 'ubuntu-latest' || matrix.os == 'windows-latest') && '--allow-missing-baseline' || '' }} \
             | tee bench-report.md
       - name: Append bench report to job summary
         if: always()
+        shell: bash
         run: |
           {
             echo "## WeavePy bench"
@@ -160,14 +171,17 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-latest, macos-latest]
+        os: [ubuntu-latest, macos-latest, windows-latest]
     # RFC 0062 WS3 — the ecosystem lane in CI. Installs the manifest's
     # packages from an offline wheel cache into venvs running under the
     # built weavepy, runs each row's probe (and package self-tests),
     # and gates on tests/ecosystem/expectations.toml. Blocking, same
     # policy as regrtest. The host CPython is only used by the wheel
     # fetcher (pip download needs a real Python); the runners' system
     # cc covers source builds.
+    #
+    # The windows leg is advisory via the baseline's `measured_os`
+    # stamp (RFC 0063 WS7), not via CI config — see the regrtest job.
     steps:
       - uses: actions/checkout@v4
       - uses: dtolnay/rust-toolchain@stable
@@ -183,8 +197,12 @@ jobs:
       - name: Build weavepy CLI
         run: cargo build --release -p weavepy-cli
       - name: Fetch ecosystem wheels (no-op on cache hit)
-        run: python3 tools/ecosystem_fetch.py --dest target/ecosystem-wheels
+        # `python`, not `python3`: setup-python exposes both on
+        # ubuntu/macos (same 3.13 interpreter) but only `python` on
+        # windows runners.
+        run: python tools/ecosystem_fetch.py --dest target/ecosystem-wheels
       - name: Run ecosystem harness
+        shell: bash
         run: |
           cargo run --release -p weavepy-conformance -- ecosystem \
             --wheels target/ecosystem-wheels \
@@ -197,11 +215,13 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-latest, macos-latest]
+        os: [ubuntu-latest, macos-latest, windows-latest]
     # RFC 0062 — builds the relocatable artifact from the release CLI
     # and runs `weavepy-dist check` against it (boot, stdlib, venv +
     # pip smoke). The pip leg reuses the offline wheel cache from the
-    # ecosystem job's actions/cache key.
+    # ecosystem job's actions/cache key. On windows the builder emits
+    # the RFC 0063 WS6 zip artifact / NT layout; the check command is
+    # identical.
     steps:
       - uses: actions/checkout@v4
       - uses: dtolnay/rust-toolchain@stable
@@ -217,8 +237,12 @@ jobs:
       - name: Build weavepy CLI
         run: cargo build --release -p weavepy-cli
       - name: Fetch ecosystem wheels (no-op on cache hit)
-        run: python3 tools/ecosystem_fetch.py --dest target/ecosystem-wheels
+        # `python`, not `python3`: setup-python exposes both on
+        # ubuntu/macos (same 3.13 interpreter) but only `python` on
+        # windows runners.
+        run: python tools/ecosystem_fetch.py --dest target/ecosystem-wheels
       - name: Run dist check
+        shell: bash
         run: |
           cargo run --release -p weavepy-dist -- check \
             --wheels target/ecosystem-wheels

Cargo.toml

@@ -140,6 +140,34 @@ parking_lot           = "0.12"
 crossbeam-channel     = "0.5"
 crossbeam-utils       = "0.8"
 
+# RFC 0063 — the Windows wave: NT-native stdlib core (`_winapi`,
+# `msvcrt`, `winreg`, `_overlapped`, the CRT fd model, Winsock
+# `select`). Target-scoped to Windows builds only; the feature list
+# is the union of the Win32 namespaces those modules consume.
+windows-sys = { version = "0.61", features = [
+    "Win32_Foundation",
+    "Win32_Globalization",
+    "Win32_Networking_WinSock",
+    "Win32_Security",
+    "Win32_Security_Cryptography",
+    "Win32_Storage_FileSystem",
+    "Win32_System_Console",
+    "Win32_System_Diagnostics_Debug",
+    "Win32_System_Environment",
+    "Win32_System_IO",
+    "Win32_System_Ioctl",
+    "Win32_System_LibraryLoader",
+    "Win32_System_Memory",
+    "Win32_System_Pipes",
+    "Win32_System_Registry",
+    "Win32_System_SystemInformation",
+    "Win32_System_SystemServices",
+    "Win32_System_Threading",
+    "Win32_System_WindowsProgramming",
+    "Win32_UI_Shell",
+    "Win32_UI_WindowsAndMessaging",
+] }
+
 # RFC 0032 — tier-2 JIT backend (Cranelift). Only compiled when the
 # `jit` feature is enabled (off by default); CI exercises it via
 # `--all-features`. MSRV floor for these is Rust 1.93.