example update

README.md

@@ -319,44 +319,62 @@ steps:
 **Restore-Only Cache**
 
 ```yaml
-## In some workflows, you may want to restore a cache without saving it. This can help reduce cache writes and storage usage in workflows that only need to read from cache
+# In some workflows, you may want to restore a cache without saving it. This can help reduce cache writes and storage usage in workflows that only need to read from cache
 jobs:
   build:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
         os: [ubuntu-latest, macos-latest, windows-latest]
+
+
     steps:
       - uses: actions/checkout@v5
+
       - name: Setup Go
         id: setup-go
         uses: actions/setup-go@v6
         with:
-          go-version: '1.24'
+          go-version: '1.24.10'
           cache: false
+
+      # Capture Go cache locations
       - name: Set Go cache variables (Linux/macOS)
         if: runner.os != 'Windows'
         run: |
           echo "GO_MOD_CACHE=$(go env GOMODCACHE)" >> $GITHUB_ENV
           echo "GO_BUILD_CACHE=$(go env GOCACHE)" >> $GITHUB_ENV
+
       - name: Set Go cache variables (Windows)
         if: runner.os == 'Windows'
         shell: pwsh
         run: |
           echo "GO_MOD_CACHE=$(go env GOMODCACHE)" | Out-File $env:GITHUB_ENV -Append
           echo "GO_BUILD_CACHE=$(go env GOCACHE)"   | Out-File $env:GITHUB_ENV -Append
-      - name: Save lowercase arch (POSIX)
+
+      # runner.arch casing differs across platforms (e.g. X64 vs x64).
+      # Normalizing it avoids cache key mismatches.
+      - name: Normalize runner architecture (Linux/macOS)
         if: runner.os != 'Windows'
+        shell: bash
         run: echo "ARCH=$(echo '${{ runner.arch }}' | tr '[:upper:]' '[:lower:]')" >> $GITHUB_ENV
-      - name: Save lowercase arch (Windows)
+
+      - name: Normalize runner architecture (Windows)
         if: runner.os == 'Windows'
         shell: pwsh
         run: |
           $arch = "${{ runner.arch }}".ToLower()
           echo "ARCH=$arch" | Out-File $env:GITHUB_ENV -Append
-      - name: Set cache OS suffix (Ubuntu only)
-        if: runner.os == 'Linux'
-        run: echo "CACHE_OS_SUFFIX=$ImageOS-" >> $GITHUB_ENV
+
+      # Always define CACHE_OS_SUFFIX so it is safe to use in cache keys
+      - name: Set cache OS suffix
+        shell: bash
+        run: |
+          echo "CACHE_OS_SUFFIX=" >> $GITHUB_ENV
+          if [ "${{ runner.os }}" = "Linux" ]; then
+            echo "CACHE_OS_SUFFIX=$ImageOS-" >> $GITHUB_ENV
+          fi
+
       - name: Restore Go cache
         id: go-cache
         uses: actions/cache/restore@v4
@@ -365,8 +383,10 @@ jobs:
             ${{ env.GO_MOD_CACHE }}
             ${{ env.GO_BUILD_CACHE }}
           key: setup-go-${{ runner.os }}-${{ env.ARCH }}-${{ env.CACHE_OS_SUFFIX }}go-${{ steps.setup-go.outputs.go-version }}-${{ hashFiles('**/go.sum') }}
+
       - name: Download modules
         run: go mod download
+
       - name: Build
         run: go build ./...
 ```