ctypeslib-linux workflow (trolldbois/ctypeslib)
The ctypeslib-linux workflow from trolldbois/ctypeslib, explained and optimized by Latchkey.
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What it does
This is the ctypeslib-linux workflow from the trolldbois/ctypeslib 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
# good example https://github.com/thenewguy/django-randomfields/blob/master/.github/workflows/sdist.yml
name: ctypeslib-linux
on: [push, pull_request]
jobs:
check-package-build:
name: Build & inspect our package.
runs-on: ubuntu-latest
steps:
- uses: actions/checkout@v4
with:
# get all history and tags for setuptools_scm to find the right version
fetch-depth: 0
- name: Install build dependencies
run: |
pip install setuptools setuptools_scm wheel build
- name: Build package wheel
run: python -m build -w
- name: Upload built artifacts.
uses: actions/upload-artifact@v4
# By default, the artifacts and log files generated by workflows are retained for 90 days before they are automatically deleted.
with:
name: Packages
path: ./dist/*
# - uses: hynek/build-and-inspect-python-package@v1
# id: build-package
# packages are uploaded to Packages
test:
needs: check-package-build
runs-on: ubuntu-latest
strategy:
matrix:
# os: [ubuntu-latest]
# python-version: [3.13]
# clang-version: ['19']
os: [ubuntu-latest, macos-latest, windows-latest]
python-version: [ '3.10', '3.11', '3.12', '3.13' ]
clang-version: ['17', '18', '19']
steps:
- uses: actions/checkout@v4
- name: Set up Python
uses: actions/setup-python@v5
with:
python-version: ${{ matrix.python-version }}
- name: Install Clang
uses: egor-tensin/setup-clang@v1
with:
version: ${{ matrix.clang-version }}
platform: x64
- name: Install dependencies
run: |
python -m pip install --upgrade pip
pip install setuptools setuptools_scm clang==${{ matrix.clang-version }}.* coveralls coverage[toml]
- name: build test libs
run: |
CFLAGS="-Wall -Wextra -Werror -std=c99 -pedantic -fpic"
LDFLAGS="-shared"
clang $CFLAGS $LDFLAGS -o test/data/test-callbacks.so test/data/test-callbacks.c
- name: Show LD_LIBRARY_PATH
run: |
echo $LD_LIBRARY_PATH
echo $PWD
echo $(pwd)
echo ${{runner.os == 'Linux' }}
- name: Update Linux LD_LIBRARY_PATH
if: ${{runner.os == 'Linux' }}
run: |
echo "LD_LIBRARY_PATH=$(pwd)/test/data/:$LD_LIBRARY_PATH" >> $GITHUB_ENV
- name: Update Windows PATH
if: ${{runner.os == 'Windows' }}
run: |
echo "PATH=$(pwd)/test/data/:$Env:PATH" >> $GITHUB_ENV
- name: Update macOS PATH
if: ${{runner.os == 'macOS' }}
run: |
echo "DYLD_LIBRARY_PATH=$(pwd)/test/data/:$DYLD_LIBRARY_PATH" >> $GITHUB_ENV
- uses: actions/download-artifact@v4
with:
name: Packages
path: ~/packages/
- name: Install the package that was built
run: |
pip install ~/packages/ctypeslib2*.whl
- name: Show the versions involved
run: clang2py --version
- name: Run tests with Unittest and coverage
run: |
coverage run --source=ctypeslib -m unittest test.alltests
- name: Coveralls
uses: coverallsapp/github-action@v2
with:
parallel: true
flag-name: run-${{ join(matrix.*, ' - ') }}
coveralls_finish:
needs: test
runs-on: ubuntu-latest
steps:
- name: Coveralls Finished
uses: coverallsapp/github-action@v2
with:
parallel-finished: 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.
# good example https://github.com/thenewguy/django-randomfields/blob/master/.github/workflows/sdist.yml name: ctypeslib-linux on: [push, pull_request] concurrency: group: ${{ github.workflow }}-${{ github.ref }} cancel-in-progress: true jobs: check-package-build: timeout-minutes: 30 name: Build & inspect our package. runs-on: latchkey-small steps: - uses: actions/checkout@v4 with: # get all history and tags for setuptools_scm to find the right version fetch-depth: 0 - name: Install build dependencies run: | pip install setuptools setuptools_scm wheel build - name: Build package wheel run: python -m build -w - name: Upload built artifacts. uses: actions/upload-artifact@v4 # By default, the artifacts and log files generated by workflows are retained for 90 days before they are automatically deleted. with: name: Packages path: ./dist/* # - uses: hynek/build-and-inspect-python-package@v1 # id: build-package # packages are uploaded to Packages test: timeout-minutes: 30 needs: check-package-build runs-on: latchkey-small strategy: matrix: # os: [ubuntu-latest] # python-version: [3.13] # clang-version: ['19'] os: [ubuntu-latest, macos-latest, windows-latest] python-version: [ '3.10', '3.11', '3.12', '3.13' ] clang-version: ['17', '18', '19'] steps: - uses: actions/checkout@v4 - name: Set up Python uses: actions/setup-python@v5 with: cache: 'pip' python-version: ${{ matrix.python-version }} - name: Install Clang uses: egor-tensin/setup-clang@v1 with: version: ${{ matrix.clang-version }} platform: x64 - name: Install dependencies run: | python -m pip install --upgrade pip pip install setuptools setuptools_scm clang==${{ matrix.clang-version }}.* coveralls coverage[toml] - name: build test libs run: | CFLAGS="-Wall -Wextra -Werror -std=c99 -pedantic -fpic" LDFLAGS="-shared" clang $CFLAGS $LDFLAGS -o test/data/test-callbacks.so test/data/test-callbacks.c - name: Show LD_LIBRARY_PATH run: | echo $LD_LIBRARY_PATH echo $PWD echo $(pwd) echo ${{runner.os == 'Linux' }} - name: Update Linux LD_LIBRARY_PATH if: ${{runner.os == 'Linux' }} run: | echo "LD_LIBRARY_PATH=$(pwd)/test/data/:$LD_LIBRARY_PATH" >> $GITHUB_ENV - name: Update Windows PATH if: ${{runner.os == 'Windows' }} run: | echo "PATH=$(pwd)/test/data/:$Env:PATH" >> $GITHUB_ENV - name: Update macOS PATH if: ${{runner.os == 'macOS' }} run: | echo "DYLD_LIBRARY_PATH=$(pwd)/test/data/:$DYLD_LIBRARY_PATH" >> $GITHUB_ENV - uses: actions/download-artifact@v4 with: name: Packages path: ~/packages/ - name: Install the package that was built run: | pip install ~/packages/ctypeslib2*.whl - name: Show the versions involved run: clang2py --version - name: Run tests with Unittest and coverage run: | coverage run --source=ctypeslib -m unittest test.alltests - name: Coveralls uses: coverallsapp/github-action@v2 with: parallel: true flag-name: run-${{ join(matrix.*, ' - ') }} coveralls_finish: timeout-minutes: 30 needs: test runs-on: latchkey-small steps: - name: Coveralls Finished uses: coverallsapp/github-action@v2 with: parallel-finished: 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 useslatchkey-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.
3 third-party actions are referenced by a movable tag. Pin them 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 3 jobs (38 with the matrix expanded) per trigger. On Latchkey the same minutes cost up to 58% less than GitHub-hosted, with zero queue time.