Recent Changes

.buckconfig

@@ -15,7 +15,10 @@ ignore = \
     app_dep_graph_rules, \
     examples, \
     integrations/rust-project/tests, \
-    tests
+    tests, \
+    .jj, \
+    .git, \
+    target
 
 [rust]
 default_edition = 2024

.envrc

@@ -3,7 +3,7 @@ if ! has nix_direnv_version || ! nix_direnv_version 3.0.5; then
   source_url "https://raw.githubusercontent.com/nix-community/nix-direnv/3.0.5/direnvrc" "sha256-RuwIS+QKFj/T9M2TFXScjBsLR6V3A17YVoEW/Q6AZ1w="
 fi
 
-watch_file rust-toolchain
+watch_file rust-toolchain.toml
 use flake
 
 source_env_if_exists .envrc.local

.github/actions/setup_linux_env/action.yml

@@ -6,7 +6,7 @@ runs:
   - uses: SebRollen/toml-action@v1.2.0
     id: read_rust_toolchain
     with:
-      file: rust-toolchain
+      file: rust-toolchain.toml
       field: toolchain.channel
   - uses: dtolnay/rust-toolchain@v1
     with:

.github/actions/setup_macos_env/action.yml

@@ -6,7 +6,7 @@ runs:
   - uses: SebRollen/toml-action@v1.2.0
     id: read_rust_toolchain
     with:
-      file: rust-toolchain
+      file: rust-toolchain.toml
       field: toolchain.channel
   - uses: dtolnay/rust-toolchain@v1
     with:

.github/actions/setup_windows_env/action.yml

@@ -15,7 +15,7 @@ runs:
   - uses: SebRollen/toml-action@v1.2.0
     id: read_rust_toolchain
     with:
-      file: rust-toolchain
+      file: rust-toolchain.toml
       field: toolchain.channel
   - uses: dtolnay/rust-toolchain@v1
     with:

.github/dotslash-config.json

@@ -64,6 +64,38 @@
             "path": "rust-project-x86_64-unknown-linux-musl"
           }
         }
+      },
+      "starlark_fmt": {
+        "platforms": {
+          "macos-aarch64": {
+            "regex": "^starlark_fmt-aarch64-apple-darwin.zst$",
+            "path": "starlark_fmt-aarch64-apple-darwin"
+          },
+          "windows-aarch64": {
+            "regex": "^starlark_fmt-aarch64-pc-windows-msvc.exe.zst$",
+            "path": "starlark_fmt-aarch64-pc-windows-msvc.exe"
+          },
+          "linux-aarch64": {
+            "regex": "^starlark_fmt-aarch64-unknown-linux-musl.zst$",
+            "path": "starlark_fmt-aarch64-unknown-linux-musl"
+          },
+          "linux-riscv64": {
+            "regex": "^starlark_fmt-riscv64gc-unknown-linux-gnu.zst$",
+            "path": "starlark_fmt-riscv64gc-unknown-linux-gnu"
+          },
+          "macos-x86_64": {
+            "regex": "^starlark_fmt-x86_64-apple-darwin.zst$",
+            "path": "starlark_fmt-x86_64-apple-darwin"
+          },
+          "windows-x86_64": {
+            "regex": "^starlark_fmt-x86_64-pc-windows-msvc.exe.zst$",
+            "path": "starlark_fmt-x86_64-pc-windows-msvc.exe"
+          },
+          "linux-x86_64": {
+            "regex": "^starlark_fmt-x86_64-unknown-linux-musl.zst$",
+            "path": "starlark_fmt-x86_64-unknown-linux-musl"
+          }
+        }
       }
     }
 }

.github/workflows/build-and-examples.yml

@@ -7,11 +7,14 @@ permissions:
 
 jobs:
   macos-build-examples:
-    runs-on: macos-latest
+    # Pinned to macos-14: on the macos-15 runner image `latest-stable` selects an
+    # Xcode/SDK that mis-targets the deployment SDK and breaks the `cargo build`
+    # step (actions/runner-images#12758). macos-14 resolves to a known-good Xcode 16.x.
+    runs-on: macos-14
     steps:
     - uses: maxim-lobanov/setup-xcode@v1.6.0
       with:
-        xcode-version: 16.4.0
+        xcode-version: latest-stable
     - uses: actions/checkout@v6
     - uses: ./.github/actions/setup_macos_env
     - uses: ./.github/actions/init_opam
@@ -40,7 +43,7 @@ jobs:
     - uses: ./.github/actions/setup_reindeer
     - uses: ./.github/actions/build_bootstrap
   linux-build-examples:
-    runs-on: ubuntu-22.04
+    runs-on: ubuntu-26.04
     steps:
     - uses: actions/checkout@v6
     - uses: ./.github/actions/setup_linux_env
@@ -76,8 +79,11 @@ jobs:
         NATIVELINK_HEADER_RW_KEY_SECRET: ${{ secrets.NATIVELINK_HEADER_RW_KEY_SECRET }}
     - uses: ./.github/actions/setup_reindeer
     - uses: ./.github/actions/build_bootstrap
+  # The Meta-specific windows-8-core runner label does not exist on forks;
+  # fall back to the standard GitHub-hosted runner there so the job doesn't
+  # sit queued forever waiting for a runner that isn't available.
   windows-build-examples:
-    runs-on: windows-8-core
+    runs-on: ${{ github.repository_owner == 'facebook' && 'windows-8-core' || 'windows-latest' }}
     steps:
       - uses: actions/checkout@v6
       - uses: ./.github/actions/setup_windows_env

.github/workflows/build-and-test.yml

@@ -1,32 +1,41 @@
 name: Build and test
 on:
   push:
+    branches:
+      - main
   pull_request:
   workflow_dispatch: # allows manual triggering
 
 permissions:
   contents: read
 
 jobs:
+  # Runner labels are repository (owner) specific, so the Meta larger runners
+  # (4-core-ubuntu, windows-8-core) don't exist on forks and jobs requesting
+  # them would sit queued forever waiting for a runner that isn't available.
+  # Fall back to the standard GitHub-hosted runners there.
   linux-build-and-test:
-    runs-on: 4-core-ubuntu
+    runs-on: ${{ github.repository_owner == 'facebook' && '4-core-ubuntu' || 'ubuntu-latest' }}
     steps:
     - uses: actions/checkout@v6
     - uses: ./.github/actions/setup_linux_env
     - uses: ./.github/actions/build_debug
     - uses: ./.github/actions/run_test_py
   macos-build-and-test:
-    runs-on: macos-latest
+    # Pinned to macos-14: on the macos-15 runner image `latest-stable` selects an
+    # Xcode/SDK that mis-targets the deployment SDK and breaks the `cargo build`
+    # step (actions/runner-images#12758). macos-14 resolves to a known-good Xcode 16.x.
+    runs-on: macos-14
     steps:
     - uses: maxim-lobanov/setup-xcode@v1.6.0
       with:
-        xcode-version: 16.4.0
+        xcode-version: latest-stable
     - uses: actions/checkout@v6
     - uses: ./.github/actions/setup_macos_env
     - uses: ./.github/actions/build_debug
     - uses: ./.github/actions/run_test_py
   windows-build-and-test:
-    runs-on: windows-8-core
+    runs-on: ${{ github.repository_owner == 'facebook' && 'windows-8-core' || 'windows-latest' }}
     steps:
     - uses: actions/checkout@v6
     - uses: ./.github/actions/setup_windows_env

.github/workflows/build_buck2.yml

@@ -0,0 +1,163 @@
+name: Build `buck2`
+
+on:
+  workflow_call:
+    inputs:
+      buck2_version:
+        description: "Version string stamped into the binaries via BUCK2_SET_EXPLICIT_VERSION"
+        required: true
+        type: string
+      release_timestamp:
+        description: "Timestamp stamped into the binaries via BUCK2_RELEASE_TIMESTAMP"
+        required: true
+        type: string
+
+jobs:
+  get_prelude_hash:
+    name: Get the latest prelude hash
+    runs-on: ubuntu-latest
+    outputs:
+      prelude_hash: ${{ steps.get_latest_prelude_hash.outputs.prelude_hash }}
+    steps:
+      - name: Shallow clone buck2-prelude
+        run: git clone --depth=1 https://github.com/facebook/buck2-prelude
+      - name: Get latest commit hash into prelude_hash
+        id: get_latest_prelude_hash
+        run: |
+          mkdir artifacts/
+          cd buck2-prelude/
+          git rev-parse HEAD > ../artifacts/prelude_hash
+          echo "prelude_hash=$(git rev-parse HEAD)" >> "$GITHUB_OUTPUT"
+      - name: Upload prelude_hash
+        uses: actions/upload-artifact@v6
+        with:
+          path: artifacts/prelude_hash
+          name: prelude_hash
+
+  build:
+    needs:
+      - get_prelude_hash
+    strategy:
+      fail-fast: false
+      matrix:
+        target:
+          - os: 'ubuntu-26.04'
+            triple: 'aarch64-unknown-linux-gnu'
+            cross: true
+          - os: 'ubuntu-26.04'
+            triple: 'aarch64-unknown-linux-musl'
+            cross: true
+          - os: 'ubuntu-26.04'
+            triple: 'x86_64-unknown-linux-gnu'
+          - os: 'ubuntu-26.04'
+            triple: 'x86_64-unknown-linux-musl'
+            cross: true
+          - os: 'ubuntu-26.04'
+            triple: 'riscv64gc-unknown-linux-gnu'
+            cross: true
+          - os: 'macos-15'
+            triple: 'aarch64-apple-darwin'
+            cross: true
+          - os: 'macos-15'
+            triple: 'x86_64-apple-darwin'
+          - os: 'windows-2025'
+            triple: 'x86_64-pc-windows-msvc'
+            is_windows: true
+          - os: 'windows-11-arm'
+            triple: 'aarch64-pc-windows-msvc'
+            is_windows: true
+    runs-on: ${{ matrix.target.os }}
+
+    steps:
+      - uses: actions/checkout@v6
+        with:
+          fetch-depth: 0
+      - uses: SebRollen/toml-action@v1.0.2
+        id: read_rust_toolchain
+        with:
+          file: 'rust-toolchain.toml'
+          field: 'toolchain.channel'
+      - uses: dtolnay/rust-toolchain@v1
+        with:
+          toolchain: ${{ steps.read_rust_toolchain.outputs.value }}
+          targets: ${{ matrix.target.triple }}
+      - uses: Swatinem/rust-cache@v2
+        with:
+          prefix-key: buck2-upload
+          key: ${{ matrix.target.triple }}
+      - uses: actions-rs/install@v0.1
+        if: matrix.target.cross
+        with:
+          crate: cross
+          version: latest
+      - name: Set variables
+        id: set_variables
+        shell: bash
+        run: |
+          if [ -n "${{ matrix.target.is_windows }}" ]; then
+            echo "buck2_out=target/${{ matrix.target.triple }}/release/buck2.exe" >> "$GITHUB_OUTPUT"
+            echo "buck2_zst=artifacts/buck2-${{ matrix.target.triple }}.exe.zst" >> "$GITHUB_OUTPUT"
+            echo "buck2_rust_project_out=target/${{ matrix.target.triple }}/release/rust-project.exe" >> "$GITHUB_OUTPUT"
+            echo "buck2_rust_project_zst=artifacts/rust-project-${{ matrix.target.triple }}.exe.zst" >> "$GITHUB_OUTPUT"
+            echo "starlark_fmt_out=target/${{ matrix.target.triple }}/release/starlark_fmt.exe" >> "$GITHUB_OUTPUT"
+            echo "starlark_fmt_zst=artifacts/starlark_fmt-${{ matrix.target.triple }}.exe.zst" >> "$GITHUB_OUTPUT"
+          else
+            echo "buck2_out=target/${{ matrix.target.triple }}/release/buck2" >> "$GITHUB_OUTPUT"
+            echo "buck2_zst=artifacts/buck2-${{ matrix.target.triple }}.zst" >> "$GITHUB_OUTPUT"
+            echo "buck2_rust_project_out=target/${{ matrix.target.triple }}/release/rust-project" >> "$GITHUB_OUTPUT"
+            echo "buck2_rust_project_zst=artifacts/rust-project-${{ matrix.target.triple }}.zst" >> "$GITHUB_OUTPUT"
+            echo "starlark_fmt_out=target/${{ matrix.target.triple }}/release/starlark_fmt" >> "$GITHUB_OUTPUT"
+            echo "starlark_fmt_zst=artifacts/starlark_fmt-${{ matrix.target.triple }}.zst" >> "$GITHUB_OUTPUT"
+          fi
+      - name: Build
+        shell: bash
+        env:
+          # BUCK2 prefixed variables used within the build to stamp in a version information
+          # BUCK2_SET_EXPLICIT_VERSION will populate the buck2 --version string
+          BUCK2_RELEASE_TIMESTAMP: ${{ inputs.release_timestamp }}
+          BUCK2_SET_EXPLICIT_VERSION: ${{ inputs.buck2_version }}
+          RUSTFLAGS: "--cfg tokio_unstable -C strip=debuginfo -C codegen-units=1"
+        run: |
+          # aarch64-linux builds need JEMALLOC_SYS_WITH_LG_PAGE=16
+          # this is for e.g. linux running on apple silicon with native 16k pages
+          if [[ "${{ matrix.target.triple }}" == aarch64-unknown-linux* ]]; then
+            export JEMALLOC_SYS_WITH_LG_PAGE=16
+          fi
+
+          if [ -n "${{ matrix.target.cross }}" ]; then
+            CARGO=cross
+          else
+            CARGO=cargo
+          fi
+          $CARGO build --release --bin buck2 --bin rust-project --bin starlark_fmt --target ${{ matrix.target.triple }}
+      - name: Sanity check with examples/with_prelude
+        if: ${{ !matrix.target.cross }}
+        shell: bash
+        run: |
+          BUCK2="$(pwd)/${{ steps.set_variables.outputs.buck2_out }}"
+          cd examples/with_prelude
+          # TODO: rust examples don't work on windows + arm64
+          if [[ "${{ matrix.target.triple }}" == "aarch64-pc-windows-msvc" ]]; then
+            TARGETS="cpp/... python/..."
+          else
+            TARGETS="rust/... cpp/... python/..."
+          fi
+          "$BUCK2" build $TARGETS -v=2
+        # TODO: investigate segmentation fault on windows-11-arm
+        continue-on-error: ${{ matrix.target.triple == 'aarch64-pc-windows-msvc' }}
+      - name: Install zstd
+        shell: pwsh
+        if: ${{ matrix.target.os == 'windows-11-arm' }}
+        run: choco install zstandard
+      - name: Move binary to artifacts/
+        shell: bash
+        run: |
+          mkdir artifacts
+          zstd -z ${{ steps.set_variables.outputs.buck2_out }} -o ${{ steps.set_variables.outputs.buck2_zst }}
+          zstd -z ${{ steps.set_variables.outputs.buck2_rust_project_out }} -o ${{ steps.set_variables.outputs.buck2_rust_project_zst }}
+          zstd -z ${{ steps.set_variables.outputs.starlark_fmt_out }} -o ${{ steps.set_variables.outputs.starlark_fmt_zst }}
+      - name: Upload
+        uses: actions/upload-artifact@v6
+        with:
+          name: buck2-${{ matrix.target.triple }}
+          path: artifacts/

.github/workflows/release.yml

@@ -0,0 +1,61 @@
+name: Manually release `buck2`
+
+on:
+  workflow_dispatch:
+
+permissions:
+  contents: write
+
+jobs:
+  set_version_info:
+    name: Define the version info for this release
+    runs-on: ubuntu-latest
+    outputs:
+      buck2_version: ${{ steps.define_version_info.outputs.buck2_version }}
+      release_timestamp: ${{ steps.define_version_info.outputs.release_timestamp }}
+      tag: ${{ steps.define_version_info.outputs.tag }}
+    steps:
+      - name: Define version info
+        id: define_version_info
+        run: |
+          # Git tags cannot contain ':', so use '.' between the time components
+          tag=$(date -u +%Y-%m-%d-%H.%M.%S)
+
+          echo "tag=$tag" >> "$GITHUB_OUTPUT"
+          echo "release_timestamp=$(date -u +%Y-%m-%dT%H:%M:%SZ)" >> "$GITHUB_OUTPUT"
+          echo "buck2_version=$tag-${{ github.sha }}" >> "$GITHUB_OUTPUT"
+      - name: Display version info
+        run: |
+          echo "tag: ${{ steps.define_version_info.outputs.tag }}"
+          echo "buck2_version: ${{ steps.define_version_info.outputs.buck2_version }}"
+
+  build:
+    name: Build `buck2`
+    needs:
+      - set_version_info
+    uses: ./.github/workflows/build_buck2.yml
+    with:
+      buck2_version: ${{ needs.set_version_info.outputs.buck2_version }}
+      release_timestamp: ${{ needs.set_version_info.outputs.release_timestamp }}
+
+  release:
+    name: Release the new tag
+    needs:
+      - set_version_info
+      - build
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v6
+        with:
+          fetch-depth: 0
+      # Publish a new tag and upload all artifacts from the build
+      - uses: ./.github/actions/publish_tag
+        with:
+          tag: ${{ needs.set_version_info.outputs.tag }}
+          github_token: ${{ secrets.GITHUB_TOKEN }}
+      - uses: facebook/dotslash-publish-release@v1
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          config: .github/dotslash-config.json
+          tag: ${{ needs.set_version_info.outputs.tag }}