Rewrite fetch in Rust

.cargo/config.toml

@@ -0,0 +1,2 @@
+[build]
+rustflags = ["--cfg", "reqwest_unstable"]

.github/dependabot.yml

@@ -1,6 +1,6 @@
 version: 2
 updates:
-  - package-ecosystem: gomod
+  - package-ecosystem: cargo
     directory: "/"
     schedule:
       interval: daily

.github/workflows/ci.yml

@@ -1,100 +1,65 @@
 name: ci
 
 on:
+  push:
+    branches: ["main"]
   pull_request:
     branches: ["main"]
 
 env:
-  GO_VERSION: "1.26.3"
+  CARGO_TERM_COLOR: always
+
+permissions:
+  contents: read
 
 jobs:
-  check:
+  ci:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v6
-
-      - name: Setup Go
-        uses: actions/setup-go@v6
         with:
-          go-version: ${{ env.GO_VERSION }}
-
-      - name: Format
-        run: gofmt -s -w . && git diff --exit-code
+          fetch-depth: 0
 
-      - name: Mod download
-        run: go mod download
+      - name: Setup Rust
+        uses: dtolnay/rust-toolchain@stable
+        with:
+          components: clippy,rustfmt
 
-      - name: Tidy
-        run: go mod tidy && git diff --exit-code
+      - name: Rust format
+        run: cargo fmt --check
 
-      - name: Mod verify
-        run: go mod verify
+      - name: Rust lint
+        run: cargo clippy --locked --all-targets --all-features -- -D warnings
 
-      - name: Lint
-        uses: dominikh/staticcheck-action@v1.4.1
-        with:
-          version: "2026.1"
-          install-go: false
+      - name: Rust unit tests
+        run: cargo test --locked --all-features --bins
 
-  test:
+  integration:
+    name: integration (${{ matrix.os }})
     runs-on: ${{ matrix.os }}
     strategy:
+      fail-fast: false
       matrix:
         os: ["ubuntu-latest", "macos-latest", "windows-latest"]
     steps:
       - uses: actions/checkout@v6
         with:
           fetch-depth: 0
 
-      - name: Setup Go
-        uses: actions/setup-go@v6
-        with:
-          go-version: ${{ env.GO_VERSION }}
+      - name: Setup Rust
+        uses: dtolnay/rust-toolchain@stable
 
-      - name: Test
-        run: go test -v -parallel 8 ./...
+      - name: Install protoc (Linux)
+        if: runner.os == 'Linux'
+        run: sudo apt-get update && sudo apt-get install -y protobuf-compiler
 
-  build:
-    runs-on: ubuntu-latest
-    strategy:
-      matrix:
-        build:
-          - linux-amd64
-          - linux-arm64
-          - darwin-amd64
-          - darwin-arm64
-          - windows-amd64
-          - windows-arm64
-        include:
-          - build: linux-amd64
-            goos: linux
-            goarch: amd64
-          - build: linux-arm64
-            goos: linux
-            goarch: arm64
-          - build: darwin-amd64
-            goos: darwin
-            goarch: amd64
-          - build: darwin-arm64
-            goos: darwin
-            goarch: arm64
-          - build: windows-amd64
-            goos: windows
-            goarch: amd64
-          - build: windows-arm64
-            goos: windows
-            goarch: arm64
-    steps:
-      - uses: actions/checkout@v6
+      - name: Install protoc (macOS)
+        if: runner.os == 'macOS'
+        run: brew install protobuf
 
-      - name: Setup Go
-        uses: actions/setup-go@v6
-        with:
-          go-version: ${{ env.GO_VERSION }}
+      - name: Install protoc (Windows)
+        if: runner.os == 'Windows'
+        run: choco install protoc -y
 
-      - name: Go build
-        env:
-          GOOS: ${{ matrix.goos }}
-          GOARCH: ${{ matrix.goarch }}
-          CGO_ENABLED: "0"
-        run: go install -trimpath -ldflags="-s -w"
+      - name: Rust integration tests against Rust binary
+        run: cargo test --locked --all-features --test integration -- --test-threads=1

.github/workflows/release.yml

@@ -5,85 +5,87 @@ on:
     types: [published]
 
 env:
-  GO_VERSION: "1.26.3"
+  CARGO_TERM_COLOR: always
+
+permissions:
+  contents: read
 
 jobs:
   release:
-    runs-on: ubuntu-latest
+    runs-on: ${{ matrix.os }}
     permissions:
       contents: write
-    env:
-      ASSET: ""
-      BIN_NAME: fetch
     strategy:
       matrix:
-        build:
-          - linux-amd64
-          - linux-arm64
-          - darwin-amd64
-          - darwin-arm64
-          - windows-amd64
-          - windows-arm64
         include:
           - build: linux-amd64
-            goos: linux
-            goarch: amd64
+            os: ubuntu-latest
+            target: x86_64-unknown-linux-gnu
+            artifact: tar.gz
           - build: linux-arm64
-            goos: linux
-            goarch: arm64
+            os: ubuntu-latest
+            target: aarch64-unknown-linux-gnu
+            artifact: tar.gz
           - build: darwin-amd64
-            goos: darwin
-            goarch: amd64
+            os: macos-latest
+            target: x86_64-apple-darwin
+            artifact: tar.gz
           - build: darwin-arm64
-            goos: darwin
-            goarch: arm64
+            os: macos-latest
+            target: aarch64-apple-darwin
+            artifact: tar.gz
           - build: windows-amd64
-            goos: windows
-            goarch: amd64
+            os: windows-latest
+            target: x86_64-pc-windows-msvc
+            artifact: zip
           - build: windows-arm64
-            goos: windows
-            goarch: arm64
+            os: windows-latest
+            target: aarch64-pc-windows-msvc
+            artifact: zip
     steps:
       - uses: actions/checkout@v6
         with:
           fetch-depth: 0
 
-      - name: Setup Go
-        uses: actions/setup-go@v6
+      - name: Setup Rust
+        uses: dtolnay/rust-toolchain@stable
         with:
-          go-version: ${{ env.GO_VERSION }}
+          targets: ${{ matrix.target }}
 
-      - name: Set bin name
-        if: ${{ matrix.goos == 'windows' }}
-        run: echo "BIN_NAME=fetch.exe" >> $GITHUB_ENV
+      - name: Install Linux ARM64 linker
+        if: matrix.target == 'aarch64-unknown-linux-gnu'
+        run: sudo apt-get update && sudo apt-get install -y gcc-aarch64-linux-gnu
 
-      - name: Go build
+      - name: Rust build
         env:
-          GOOS: ${{ matrix.goos }}
-          GOARCH: ${{ matrix.goarch }}
-          CGO_ENABLED: "0"
-        run: go build -trimpath -ldflags="-s -w -buildid=" -o ${{ env.BIN_NAME }}
+          CARGO_TARGET_AARCH64_UNKNOWN_LINUX_GNU_LINKER: aarch64-linux-gnu-gcc
+          FETCH_VERSION: ${{ github.ref_name }}
+        run: cargo build --release --locked --target ${{ matrix.target }}
 
       - name: Build archive (unix)
-        if: ${{ matrix.goos != 'windows' }}
+        if: matrix.artifact == 'tar.gz'
         shell: bash
         run: |
-          staging="fetch-${{ github.ref_name }}-${{ matrix.goos }}-${{ matrix.goarch }}"
-          tar czf "$staging.tar.gz" fetch
-          echo "ASSET=$staging.tar.gz" >> $GITHUB_ENV
+          staging="fetch-${{ github.ref_name }}-${{ matrix.build }}"
+          mkdir "$staging"
+          cp "target/${{ matrix.target }}/release/fetch" "$staging/fetch"
+          tar czf "$staging.tar.gz" -C "$staging" fetch
+          echo "ASSET=$staging.tar.gz" >> "$GITHUB_ENV"
 
       - name: Build archive (windows)
-        if: ${{ matrix.goos == 'windows' }}
-        shell: bash
+        if: matrix.artifact == 'zip'
+        shell: pwsh
         run: |
-          staging="fetch-${{ github.ref_name }}-${{ matrix.goos }}-${{ matrix.goarch }}"
-          zip "$staging.zip" fetch.exe
-          echo "ASSET=$staging.zip" >> $GITHUB_ENV
+          $staging = "fetch-${{ github.ref_name }}-${{ matrix.build }}"
+          New-Item -ItemType Directory -Path $staging | Out-Null
+          Copy-Item "target/${{ matrix.target }}/release/fetch.exe" "$staging/fetch.exe"
+          Compress-Archive -Path "$staging/fetch.exe" -DestinationPath "$staging.zip"
+          "ASSET=$staging.zip" | Out-File -FilePath $env:GITHUB_ENV -Append
 
       - name: Upload release archive
         env:
           GH_TOKEN: ${{ github.token }}
-        run: gh release upload ${{ github.ref_name }} ${{ env.ASSET }}
+        run: gh release upload ${{ github.ref_name }} ${{ env.ASSET }} --clobber
 
   latest:
     runs-on: "ubuntu-latest"

.gitignore

@@ -1,3 +1,4 @@
 /.claude
 /bin
 /scratch
+/target