Publish to PyPI on Tag workflow (halcy/Mastodon.py)

The Publish to PyPI on Tag workflow from halcy/Mastodon.py, explained and optimized by Latchkey.

What it does

This is the Publish to PyPI on Tag workflow from the halcy/Mastodon.py 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

# Pipeline to build and publish to pypi on tag starting with v

name: Publish to PyPI on Tag


on:
  push:
    tags:
      - "v*"


permissions:
  contents: read

  id-token: write


jobs:
  build-and-publish:
    runs-on: ubuntu-latest

    steps:
      - name: Checkout

        uses: actions/checkout@v4


      - name: Set up Python

        uses: actions/setup-python@v5

        with:
          python-version: "3.12"


      - name: Install build tools

        run: |

          python -m pip install --upgrade pip

          python -m pip install build twine


      - name: Build sdist and wheel

        run: |

          python -m build

          twine check dist/*


      - name: Publish to PyPI (Trusted Publishing)

        uses: pypa/gh-action-pypi-publish@release/v1

        with:
          verbose: true

          

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.

# Pipeline to build and publish to pypi on tag starting with v

name: Publish to PyPI on Tag



on:

  push:

    tags:

      - "v*"



permissions:

  contents: read

  id-token: write



concurrency:

  group: ${{ github.workflow }}-${{ github.ref }}

  cancel-in-progress: true



jobs:

  build-and-publish:

    timeout-minutes: 30

    runs-on: latchkey-small

    steps:

      - name: Checkout

        uses: actions/checkout@v4



      - name: Set up Python

        uses: actions/setup-python@v5

        with:

          cache: 'pip'

          python-version: "3.12"



      - name: Install build tools

        run: |

          python -m pip install --upgrade pip

          python -m pip install build twine



      - name: Build sdist and wheel

        run: |

          python -m build

          twine check dist/*



      - name: Publish to PyPI (Trusted Publishing)

        uses: pypa/gh-action-pypi-publish@release/v1

        with:

          verbose: true

          

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.
• Cancel superseded runs when a branch or PR gets a newer push.
• 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.

1 third-party action is referenced by a movable tag. Pin it to the commit SHA (Latchkey resolves and applies this automatically) so a repointed tag cannot change what runs.

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 1 job per trigger. On Latchkey the same minutes cost up to 58% less than GitHub-hosted, with zero queue time.

Actions used in this workflow