Migrate CI to hosted Cirrus Runners

.github/actions/configure-docker/action.yml

@@ -0,0 +1,52 @@
+name: 'Configure Docker'
+description: 'Set up Docker build driver and configure build cache args'
+inputs:
+  use-cirrus:
+    description: 'Use cirrus cache'
+    required: true
+runs:
+  using: 'composite'
+  steps:
+    - name: Set up Docker Buildx
+      uses: docker/setup-buildx-action@v3
+      with:
+        # Use host network to allow access to cirrus gha cache running on the host
+        driver-opts: |
+          network=host
+
+    # This is required to allow buildkit to access the actions cache
+    - name: Expose actions cache variables
+      uses: actions/github-script@v6
+      with:
+        script: |
+          core.exportVariable('ACTIONS_CACHE_URL', process.env['ACTIONS_CACHE_URL'])
+          core.exportVariable('ACTIONS_RUNTIME_TOKEN', process.env['ACTIONS_RUNTIME_TOKEN'])
+
+    - name: Construct docker build cache args
+      shell: bash
+      run: |
+        # Configure docker build cache backend
+        #
+        # On forks the gha cache will work but will use Github's cache backend.
+        # Docker will check for variables $ACTIONS_CACHE_URL, $ACTIONS_RESULTS_URL and $ACTIONS_RUNTIME_TOKEN
+        # which are set automatically when running on GitHub infra: https://docs.docker.com/build/cache/backends/gha/#synopsis
+
+        # Use cirrus cache host
+        if [[ ${{ inputs.use-cirrus }} == 'true' ]]; then
+          url_args="url=${CIRRUS_CACHE_HOST},url_v2=${CIRRUS_CACHE_HOST}"
+        else
+          url_args=""
+        fi
+
+        # Always optimistically --cache‑from in case a cache blob exists
+        args=(--cache-from "type=gha${url_args:+,${url_args}},scope=${CONTAINER_NAME}")
+
+        # If this is a push to the default branch, also add --cache‑to to save the cache
+        if [[ ${{ github.event_name }} == "push" && ${{ github.ref_name }} == ${{ github.event.repository.default_branch }} ]]; then
+          args+=(--cache-to "type=gha${url_args:+,${url_args}},mode=max,ignore-error=true,scope=${CONTAINER_NAME}")
+        fi
+
+        # Always `--load` into docker images (needed when using the `docker-container` build driver).
+        args+=(--load)
+
+        echo "DOCKER_BUILD_CACHE_ARG=${args[*]}" >> $GITHUB_ENV

.github/actions/configure-environment/action.yml

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+name: 'Configure environment'
+description: 'Configure CI, cache and container name environment variables'
+runs:
+  using: 'composite'
+  steps:
+    - name: Set CI and cache directories
+      shell: bash
+      run: |
+        echo "BASE_ROOT_DIR=${{ runner.temp }}" >> "$GITHUB_ENV"
+        echo "BASE_BUILD_DIR=${{ runner.temp }}/build" >> "$GITHUB_ENV"
+        echo "CCACHE_DIR=${{ runner.temp }}/ccache_dir" >> $GITHUB_ENV
+        echo "DEPENDS_DIR=${{ runner.temp }}/depends" >> "$GITHUB_ENV"
+        echo "BASE_CACHE=${{ runner.temp }}/depends/built" >> $GITHUB_ENV
+        echo "SOURCES_PATH=${{ runner.temp }}/depends/sources" >> $GITHUB_ENV
+        echo "PREVIOUS_RELEASES_DIR=${{ runner.temp }}/previous_releases" >> $GITHUB_ENV
+
+    - name: Set cache hashes
+      shell: bash
+      run: |
+        echo "DEPENDS_HASH=$(git ls-tree HEAD depends "ci/test/$FILE_ENV" | sha256sum | cut -d' ' -f1)" >> $GITHUB_ENV
+        echo "PREVIOUS_RELEASES_HASH=$(git ls-tree HEAD test/get_previous_releases.py | sha256sum | cut -d' ' -f1)" >> $GITHUB_ENV
+
+    - name: Get container name
+      shell: bash
+      run: |
+        source $FILE_ENV
+        echo "CONTAINER_NAME=$CONTAINER_NAME" >> "$GITHUB_ENV"

.github/actions/restore-caches/action.yml

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+name: 'Restore Caches'
+description: 'Restore ccache, depends sources, and built depends caches'
+runs:
+  using: 'composite'
+  steps:
+    - name: Restore Ccache cache
+      id: ccache-cache
+      uses: cirruslabs/cache/restore@v4
+      with:
+        path: ${{ env.CCACHE_DIR }}
+        key: ccache-${{ env.CONTAINER_NAME }}-${{ github.run_id }}
+        restore-keys: |
+          ccache-${{ env.CONTAINER_NAME }}-
+
+    - name: Restore depends sources cache
+      id: depends-sources
+      uses: cirruslabs/cache/restore@v4
+      with:
+        path: ${{ env.SOURCES_PATH }}
+        key: depends-sources-${{ env.CONTAINER_NAME }}-${{ env.DEPENDS_HASH }}
+        restore-keys: |
+          depends-sources-${{ env.CONTAINER_NAME }}-
+
+    - name: Restore built depends cache
+      id: depends-built
+      uses: cirruslabs/cache/restore@v4
+      with:
+        path: ${{ env.BASE_CACHE }}
+        key: depends-built-${{ env.CONTAINER_NAME }}-${{ env.DEPENDS_HASH }}
+        restore-keys: |
+          depends-built-${{ env.CONTAINER_NAME }}-
+
+    - name: Restore previous releases cache
+      id: previous-releases
+      uses: cirruslabs/cache/restore@v4
+      with:
+        path: ${{ env.PREVIOUS_RELEASES_DIR }}
+        key: previous-releases-${{ env.CONTAINER_NAME }}-${{ env.PREVIOUS_RELEASES_HASH }}
+        restore-keys: |
+          previous-releases-${{ env.CONTAINER_NAME }}-
+
+    - name: export cache hits
+      shell: bash
+      run: |
+        echo "depends-sources-cache-hit=${{ steps.depends-sources.outputs.cache-hit }}" >> $GITHUB_ENV
+        echo "depends-built-cache-hit=${{ steps.depends-built.outputs.cache-hit }}" >> $GITHUB_ENV
+        echo "previous-releases-cache-hit=${{ steps.previous-releases.outputs.cache-hit }}" >> $GITHUB_ENV

.github/actions/save-caches/action.yml

@@ -0,0 +1,39 @@
+name: 'Save Caches'
+description: 'Save ccache, depends sources, and built depends caches'
+runs:
+  using: 'composite'
+  steps:
+    - name: debug cache hit inputs
+      shell: bash
+      run: |
+        echo "depends sources direct cache hit to primary key: ${{ env.depends-sources-cache-hit }}"
+        echo "depends built direct cache hit to primary key: ${{ env.depends-built-cache-hit }}"
+        echo "previous releases direct cache hit to primary key: ${{ env.previous-releases-cache-hit }}"
+
+    - name: Save Ccache cache
+      uses: cirruslabs/cache/save@v4
+      if: ${{ (github.event_name == 'push') && (github.ref_name == github.event.repository.default_branch) }}
+      with:
+        path: ${{ env.CCACHE_DIR }}
+        key: ccache-${{ env.CONTAINER_NAME }}-${{ github.run_id }}
+
+    - name: Save depends sources cache
+      uses: cirruslabs/cache/save@v4
+      if: ${{ (github.event_name == 'push') && (github.ref_name == github.event.repository.default_branch) && (env.depends-sources-cache-hit != 'true') }}
+      with:
+        path: ${{ env.SOURCES_PATH }}
+        key: depends-sources-${{ env.CONTAINER_NAME }}-${{ env.DEPENDS_HASH }}
+
+    - name: Save built depends cache
+      uses: cirruslabs/cache/save@v4
+      if: ${{ (github.event_name == 'push') && (github.ref_name == github.event.repository.default_branch) && (env.depends-built-cache-hit != 'true' )}}
+      with:
+        path: ${{ env.BASE_CACHE }}
+        key: depends-built-${{ env.CONTAINER_NAME }}-${{ env.DEPENDS_HASH }}
+
+    - name: Save previous releases cache
+      uses: cirruslabs/cache/save@v4
+      if: ${{ (github.event_name == 'push') && (github.ref_name == github.event.repository.default_branch) && (env.previous-releases-cache-hit != 'true' )}}
+      with:
+        path: ${{ env.PREVIOUS_RELEASES_DIR }}
+        key: previous-releases-${{ env.CONTAINER_NAME }}-${{ env.PREVIOUS_RELEASES_HASH }}