agentsclimarketplace
Sign in

Github actions parallel test matrix

Skill kjuhwa/skills-hub/skills/ci/github-actions-parallel-test-matrix

GitHub Actions workflow uses a strategy.matrix over OS × toolchain to run all tests in parallel, with continue-on-error for nightly so unstable toolchains don't block merges.From its SKILL.md

Install
npx -y skills add kjuhwa/skills-hub --skill github-actions-parallel-test-matrix

Assembled from the repository path, not quoted from the project. Check it against their README if it does not work.

One thing to look at

  • 0 stars0 stars. Stars are a popularity signal and not a quality one, but at this level it is likely that nobody has read this closely except its author, and you would be relying on your own review.

SKILL.md

1.8 KB, 302 tokens by cl100k_base, as published. Nobody here has run it

Github Actions Parallel Test Matrix

Trigger: Multi-language project that must validate on Linux + macOS + Windows × stable + nightly without serial CI.

Steps

  • Define strategy.matrix with axes: os = [ubuntu-latest, macos-latest, windows-latest], toolchain = [stable, nightly].
  • Each matrix cell runs the full suite; GitHub spawns them in parallel.
  • Set continue-on-error: true for nightly so experimental compiler regressions don't block PRs.
  • Cache language-specific dirs (Cargo registry, pip wheels, node_modules) keyed by lockfile hash.
  • Name jobs descriptively (test (ubuntu / stable)) so matrix failures are easy to read.
  • Aggregate: require stable cells to pass; let nightly be informational only.

Counter / Caveats

  • Matrix explosion (3 OS × N toolchains) burns CI minutes — macOS and Windows are ~10x more expensive on free tier.
  • Flaky tests can fail on one cell and pass on another; quarantine flaky ones rather than rerunning blindly.
  • Setup time often dominates short test suites; cache aggressively.
  • 5GB artifact cap on free tier means you must clean up after large workflows.

Source

Extracted from magika (https://github.com/google/magika.git @ main).

Files of interest:

  • .github/workflows/rust-test.yml:1-60
  • .github/workflows/python-build-and-release-package.yml:74-120

What ships with it: 1 file

955 B alongside SKILL.md

Keep looking

Skills are one crate of 325,949. Ordering is by how many stacks a row turns up in, so the top of any crate is what has actually been picked rather than what has the most stars.