Test against downstream projects workflow (agronholm/anyio)

The Test against downstream projects workflow from agronholm/anyio, explained and optimized by Latchkey.

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Source: agronholm/anyio.github/workflows/test-downstream.ymlLicense MITView source

What it does

This is the Test against downstream projects workflow from the agronholm/anyio repository, a real project running GitHub Actions. It is shown here with attribution under its MIT license.

Below, Latchkey shows a faster, safer version produced by its optimization engine.

The workflow

workflow (.yml)

---
name: Test against downstream projects

on:
  workflow_dispatch:

jobs:
  starlette:
    name: "Starlette on Python ${{ matrix.python-version }}"
    runs-on: ubuntu-latest
    strategy:
      fail-fast: false
      matrix:
        python-version: ["3.10", "3.14"]
    steps:
      - uses: actions/checkout@v7
        with:
          repository: Kludex/starlette
      - uses: astral-sh/setup-uv@fac544c07dec837d0ccb6301d7b5580bf5edae39 # v8.2.0
        with:
          python-version: ${{ matrix.python-version }}
          enable-cache: true
      - name: Install dependencies
        run: |
          scripts/install
          pip install anyio[trio]@git+https://github.com/agronholm/anyio.git@${{ github.ref_name }}
      - name: Run tests
        run: scripts/test
      - name: Enforce coverage
        run: scripts/coverage

  httpcore:
    name: "Httpcore on Python ${{ matrix.python-version }}"
    runs-on: ubuntu-latest
    strategy:
      fail-fast: false
      matrix:
        python-version: ["3.10", "3.14"]
    steps:
      - uses: actions/checkout@v7
        with:
          repository: encode/httpcore
      - name: Install uv
        uses: actions/setup-python@v6
        with:
          python-version: "${{ matrix.python-version }}"
      - name: Install dependencies
        run: |
          scripts/install
          pip install anyio[trio]@git+https://github.com/agronholm/anyio.git@${{ github.ref_name }}
      - name: Run tests
        run: scripts/test
      - name: Enforce coverage
        run: scripts/coverage

  fastapi:
    name: "FastAPI on Python ${{ matrix.python-version }}"
    runs-on: ubuntu-latest
    strategy:
      fail-fast: false
      matrix:
        python-version: ["3.10", "3.14"]
    env:
      UV_SYSTEM_PYTHON: 1
    steps:
      - uses: actions/checkout@v7
        with:
          repository: tiangolo/fastapi
      - uses: actions/setup-python@v6
        with:
          python-version: "${{ matrix.python-version }}"
      - name: Setup uv
        uses: astral-sh/setup-uv@fac544c07dec837d0ccb6301d7b5580bf5edae39 # v8.2.0
        with:
          version: "0.11.18"
          enable-cache: true
          cache-dependency-glob: |
            pyproject.toml
            uv.lock
      - name: Install dependencies
        run: |
          uv sync --no-dev --group tests --extra all
          uv pip install anyio[trio]@git+https://github.com/agronholm/anyio.git@${{ github.ref_name }}
      - name: Run tests
        run: uv run --no-sync pytest -W ignore::UserWarning
        env:
          PYTHONPATH: ./docs_src

  litestar:
    name: "Litestar on Python ${{ matrix.python-version }}"
    runs-on: ubuntu-latest
    strategy:
      fail-fast: false
      matrix:
        python-version: ["3.10", "3.14"]
    steps:
      - uses: actions/checkout@v7
        with:
          repository: litestar-org/litestar
      - name: Set up python ${{ matrix.python-version }}
        uses: actions/setup-python@v6
        with:
          python-version: ${{ matrix.python-version }}
      - name: Install uv
        uses: astral-sh/setup-uv@fac544c07dec837d0ccb6301d7b5580bf5edae39 # v8.2.0
        with:
          version: "0.8.8"
          enable-cache: true
      - name: Install dependencies
        run: |
          uv sync
          uv pip install anyio[trio]@git+https://github.com/agronholm/anyio.git@${{ github.ref_name }}
      - name: Test
        run: uv run pytest docs/examples tests -n auto

  mcp:
    name: "Anthropic MCP on Python ${{ matrix.python-version }}"
    runs-on: ubuntu-latest
    strategy:
      fail-fast: false
      matrix:
        python-version: ["3.10", "3.14"]
        dep-resolution: ["lowest-direct", "highest"]
    steps:
      - uses: actions/checkout@v7
        with:
          repository: modelcontextprotocol/python-sdk
      - name: Install uv
        uses: astral-sh/setup-uv@fac544c07dec837d0ccb6301d7b5580bf5edae39 # v8.2.0
        with:
          enable-cache: true
          version: "0.9.5"
      - name: Install the project
        run: |
          uv sync --frozen --all-extras --python ${{ matrix.python-version }} --resolution ${{ matrix.dep-resolution }}
          uv pip install anyio[trio]@git+https://github.com/agronholm/anyio.git@${{ github.ref_name }}
      - name: Run pytest
        run: uv run --frozen --no-sync pytest

The same workflow, on Latchkey

Estimated ~20% faster on cache hits, plus fewer wasted runs and a safer supply chain. Added and changed lines are highlighted.

---
name: Test against downstream projects
 
on:
  workflow_dispatch:
 
jobs:
  starlette:
    timeout-minutes: 30
    name: "Starlette on Python ${{ matrix.python-version }}"
    runs-on: latchkey-small
    strategy:
      fail-fast: false
      matrix:
        python-version: ["3.10", "3.14"]
    steps:
      - uses: actions/checkout@v7
        with:
          repository: Kludex/starlette
      - uses: astral-sh/setup-uv@fac544c07dec837d0ccb6301d7b5580bf5edae39 # v8.2.0
        with:
          python-version: ${{ matrix.python-version }}
          enable-cache: true
      - name: Install dependencies
        run: |
          scripts/install
          pip install anyio[trio]@git+https://github.com/agronholm/anyio.git@${{ github.ref_name }}
      - name: Run tests
        run: scripts/test
      - name: Enforce coverage
        run: scripts/coverage
 
  httpcore:
    timeout-minutes: 30
    name: "Httpcore on Python ${{ matrix.python-version }}"
    runs-on: latchkey-small
    strategy:
      fail-fast: false
      matrix:
        python-version: ["3.10", "3.14"]
    steps:
      - uses: actions/checkout@v7
        with:
          repository: encode/httpcore
      - name: Install uv
        uses: actions/setup-python@v6
        with:
          cache: 'pip'
          python-version: "${{ matrix.python-version }}"
      - name: Install dependencies
        run: |
          scripts/install
          pip install anyio[trio]@git+https://github.com/agronholm/anyio.git@${{ github.ref_name }}
      - name: Run tests
        run: scripts/test
      - name: Enforce coverage
        run: scripts/coverage
 
  fastapi:
    timeout-minutes: 30
    name: "FastAPI on Python ${{ matrix.python-version }}"
    runs-on: latchkey-small
    strategy:
      fail-fast: false
      matrix:
        python-version: ["3.10", "3.14"]
    env:
      UV_SYSTEM_PYTHON: 1
    steps:
      - uses: actions/checkout@v7
        with:
          repository: tiangolo/fastapi
      - uses: actions/setup-python@v6
        with:
          cache: 'pip'
          python-version: "${{ matrix.python-version }}"
      - name: Setup uv
        uses: astral-sh/setup-uv@fac544c07dec837d0ccb6301d7b5580bf5edae39 # v8.2.0
        with:
          version: "0.11.18"
          enable-cache: true
          cache-dependency-glob: |
            pyproject.toml
            uv.lock
      - name: Install dependencies
        run: |
          uv sync --no-dev --group tests --extra all
          uv pip install anyio[trio]@git+https://github.com/agronholm/anyio.git@${{ github.ref_name }}
      - name: Run tests
        run: uv run --no-sync pytest -W ignore::UserWarning
        env:
          PYTHONPATH: ./docs_src
 
  litestar:
    timeout-minutes: 30
    name: "Litestar on Python ${{ matrix.python-version }}"
    runs-on: latchkey-small
    strategy:
      fail-fast: false
      matrix:
        python-version: ["3.10", "3.14"]
    steps:
      - uses: actions/checkout@v7
        with:
          repository: litestar-org/litestar
      - name: Set up python ${{ matrix.python-version }}
        uses: actions/setup-python@v6
        with:
          cache: 'pip'
          python-version: ${{ matrix.python-version }}
      - name: Install uv
        uses: astral-sh/setup-uv@fac544c07dec837d0ccb6301d7b5580bf5edae39 # v8.2.0
        with:
          version: "0.8.8"
          enable-cache: true
      - name: Install dependencies
        run: |
          uv sync
          uv pip install anyio[trio]@git+https://github.com/agronholm/anyio.git@${{ github.ref_name }}
      - name: Test
        run: uv run pytest docs/examples tests -n auto
 
  mcp:
    timeout-minutes: 30
    name: "Anthropic MCP on Python ${{ matrix.python-version }}"
    runs-on: latchkey-small
    strategy:
      fail-fast: false
      matrix:
        python-version: ["3.10", "3.14"]
        dep-resolution: ["lowest-direct", "highest"]
    steps:
      - uses: actions/checkout@v7
        with:
          repository: modelcontextprotocol/python-sdk
      - name: Install uv
        uses: astral-sh/setup-uv@fac544c07dec837d0ccb6301d7b5580bf5edae39 # v8.2.0
        with:
          enable-cache: true
          version: "0.9.5"
      - name: Install the project
        run: |
          uv sync --frozen --all-extras --python ${{ matrix.python-version }} --resolution ${{ matrix.dep-resolution }}
          uv pip install anyio[trio]@git+https://github.com/agronholm/anyio.git@${{ github.ref_name }}
      - name: Run pytest
        run: uv run --frozen --no-sync pytest

What changed

Run on Latchkey managed runners with one line (runs-on), which apply the fixes below automatically and self-heal transient failures. This example uses latchkey-small; pick the runner size that fits the job.
Cache dependency installs on the setup step so they are served from cache.
Add a job timeout so a hung step cannot burn hours of runner time.

What Latchkey heals here

This workflow has steps that commonly fail on transient issues (network, registries, flaky browsers). On Latchkey managed runners they are detected, retried, and self-healed instead of failing your build:

Dependency installs

This workflow runs 5 jobs (12 with the matrix expanded) per trigger. On Latchkey the same minutes cost up to 58% less than GitHub-hosted, with zero queue time.

Actions used in this workflow

actions/checkout astral-sh/setup-uv actions/setup-python