Waste detected
Biggest wins first, each with the exact config fix.
Missing dependency cache · CI
Add `Swatinem/rust-cache@v2` (the de-facto cargo cache), or an `actions/cache@v4` step keyed on `Cargo.lock`.
- uses: Swatinem/rust-cache@v2No concurrency control · CI
Add a `concurrency:` block keyed on branch to cancel superseded runs when devs push twice quickly.
concurrency:
group: ${{ github.workflow }}-${{ github.ref }}
cancel-in-progress: trueAlso found: 5 more config fixes with negligible recoverable minutes: timeouts, retention, path filters
Artifacts at default retention · CI
`upload-artifact` has no `retention-days`, so artifacts keep up to 90 days (storage cost). Set e.g. `retention-days: 7`.
- uses: actions/upload-artifact@v4
with:
name: build
path: dist/
retention-days: 7No path filters on triggers · CI
Runs on every push/PR with no `paths:` filter, so docs-only changes still trigger full CI. Add a `paths:` filter if that's common.
on:
pull_request:
paths:
- 'src/**'
- 'package.json'Premium runners (macOS / Windows) · CI
macOS bills ~10x and Windows ~2x a Linux minute. The cost estimate above assumes Linux, so your real spend is higher. Move any job that doesn't need them to `ubuntu-latest`.
jobs:
build:
runs-on: ubuntu-latest # ~10x cheaper than macos-latestScheduled workflow runs in forks · CI
The schedule has no repository guard, so forks that enable Actions inherit the cron and burn their own minutes. Gate the job with `if: github.repository == 'owner/repo'`.
jobs:
nightly:
if: github.repository == 'owner/repo'
runs-on: ubuntu-latestThird-party actions pinned to a mutable ref · CI
12 third-party actions pinned to a branch or other mutable ref, which can change under you (supply-chain risk, non-reproducible builds). Pin to a full commit SHA instead. (1 more on a major-version tag like @v4; consider full-SHA pinning there too.)
uses: dtolnay/rust-toolchain@<full-sha> # was @nightlyCopy every fix as one block (7 snippets, annotated per workflow)
# Missing dependency cache (cargo) (applies to: CI)
- uses: Swatinem/rust-cache@v2
# No concurrency control (applies to: CI)
concurrency:
group: ${{ github.workflow }}-${{ github.ref }}
cancel-in-progress: true
# Artifacts at default retention (applies to: CI)
- uses: actions/upload-artifact@v4
with:
name: build
path: dist/
retention-days: 7
# No path filters on triggers (applies to: CI)
on:
pull_request:
paths:
- 'src/**'
- 'package.json'
# Premium runners (macOS / Windows) (applies to: CI)
jobs:
build:
runs-on: ubuntu-latest # ~10x cheaper than macos-latest
# Scheduled workflow runs in forks (applies to: CI)
jobs:
nightly:
if: github.repository == 'owner/repo'
runs-on: ubuntu-latest
# Third-party actions pinned to a mutable ref (applies to: CI)
uses: dtolnay/rust-toolchain@<full-sha> # was @nightlyEach snippet is representative. Merge into the named workflow files rather than pasting wholesale.
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