CI workflow (serde-rs/serde)

The CI workflow from serde-rs/serde, explained and optimized by Latchkey.

CI health: B - good

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Source: serde-rs/serde.github/workflows/ci.ymlLicense Apache-2.0View source

What it does

This is the CI workflow from the serde-rs/serde repository, a real project running GitHub Actions. It is shown here with attribution under its Apache-2.0 license.

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

The workflow

workflow (.yml)

name: CI

on:
  push:
  pull_request:
  workflow_dispatch:
  schedule: [cron: "40 1 * * *"]

permissions:
  contents: read

env:
  RUSTFLAGS: -Dwarnings

jobs:
  test:
    name: Test suite
    runs-on: ubuntu-latest
    timeout-minutes: 45
    steps:
      - uses: actions/checkout@v7
      - uses: dtolnay/rust-toolchain@nightly
      - run: cd test_suite && cargo test --features unstable
      - uses: actions/upload-artifact@v7
        if: always()
        with:
          name: Cargo.lock
          path: Cargo.lock
        continue-on-error: true

  windows:
    name: Test suite (windows)
    runs-on: windows-latest
    timeout-minutes: 45
    steps:
      - uses: actions/checkout@v7
      - uses: dtolnay/rust-toolchain@nightly
      - run: cd test_suite && cargo test --features unstable -- --skip ui --exact

  stable:
    name: Rust ${{matrix.rust}}
    runs-on: ubuntu-latest
    strategy:
      fail-fast: false
      matrix:
        rust: [stable, beta]
    timeout-minutes: 45
    steps:
      - uses: actions/checkout@v7
      - uses: dtolnay/rust-toolchain@master
        with:
          toolchain: ${{matrix.rust}}
      - run: cd serde && cargo build --features rc
      - run: cd serde && cargo build --no-default-features
      - run: cd test_suite/no_std && cargo build

  nightly:
    name: Rust nightly${{matrix.os == 'windows' && ' (windows)' || ''}}
    runs-on: ${{matrix.os}}-latest
    strategy:
      fail-fast: false
      matrix:
        os: [ubuntu, windows]
    timeout-minutes: 45
    steps:
      - uses: actions/checkout@v7
      - uses: dtolnay/rust-toolchain@nightly
      - run: cd serde && cargo build
      - run: cd serde && cargo build --no-default-features
      - run: cd serde && cargo build --no-default-features --features alloc
      - run: cd serde && cargo build --no-default-features --features rc,alloc
      - run: cd serde && cargo build --no-default-features --features unstable
      - run: cd serde_core && cargo test --features rc,unstable
      - run: cd test_suite/no_std && cargo build
        if: matrix.os != 'windows'
      - run: cd serde_derive && cargo check --tests
        env:
          RUSTFLAGS: --cfg exhaustive ${{env.RUSTFLAGS}}
        if: matrix.os != 'windows'

  build:
    name: Rust ${{matrix.rust}}
    runs-on: ubuntu-latest
    strategy:
      fail-fast: false
      matrix:
        rust: [1.56.0, 1.60.0]
    timeout-minutes: 45
    steps:
      - uses: actions/checkout@v7
      - uses: dtolnay/rust-toolchain@master
        with:
          toolchain: ${{matrix.rust}}
      - run: sed -i '/"test_suite"/d' Cargo.toml
      - run: cd serde && cargo build --features rc
      - run: cd serde && cargo build --no-default-features
      - run: cd serde && cargo build --no-default-features --features alloc
      - run: cd serde && cargo build

  derive:
    name: Rust 1.71.0
    runs-on: ubuntu-latest
    timeout-minutes: 45
    steps:
      - uses: actions/checkout@v7
      - uses: dtolnay/rust-toolchain@1.71.0
      - run: |
          sed -i 's/proc-macro2 = { workspace = true/proc-macro2 = { version = "1"/' serde_derive*/Cargo.toml
          sed -i 's/quote = { workspace = true/quote = { version = "1"/' serde_derive*/Cargo.toml
          sed -i 's/syn = { workspace = true/syn = { version = "2"/' serde_derive*/Cargo.toml
      - run: cd serde && cargo check --no-default-features
      - run: cd serde && cargo check
      - run: cd serde_derive && cargo check

  minimal:
    name: Minimal versions
    runs-on: ubuntu-latest
    timeout-minutes: 45
    steps:
      - uses: actions/checkout@v7
      - uses: dtolnay/rust-toolchain@nightly
      - run: cargo generate-lockfile -Z minimal-versions
      - run: cargo check --locked --workspace

  doc:
    name: Documentation
    runs-on: ubuntu-latest
    timeout-minutes: 45
    env:
      RUSTDOCFLAGS: -Dwarnings
    steps:
      - uses: actions/checkout@v7
      - uses: dtolnay/rust-toolchain@nightly
      - uses: dtolnay/install@cargo-docs-rs
      - run: cargo docs-rs -p serde
      - run: cargo docs-rs -p serde_core
      - run: cargo docs-rs -p serde_derive
      - run: cargo docs-rs -p serde_derive_internals

  clippy:
    name: Clippy
    runs-on: ubuntu-latest
    if: github.event_name != 'pull_request'
    timeout-minutes: 45
    steps:
      - uses: actions/checkout@v7
      - uses: dtolnay/rust-toolchain@clippy
      - run: cd serde && cargo clippy --features rc,unstable -- -Dclippy::all -Dclippy::pedantic
      - run: cd serde_core && cargo clippy --features rc,unstable -- -Dclippy::all -Dclippy::pedantic
      - run: cd serde_derive && cargo clippy -- -Dclippy::all -Dclippy::pedantic
      - run: cd serde_derive_internals && cargo clippy -- -Dclippy::all -Dclippy::pedantic
      - run: cd test_suite && cargo clippy --tests --features unstable -- -Dclippy::all -Dclippy::pedantic
      - run: cd test_suite/no_std && cargo clippy -- -Dclippy::all -Dclippy::pedantic

  miri:
    name: Miri
    runs-on: ubuntu-latest
    timeout-minutes: 45
    steps:
      - uses: actions/checkout@v7
      - uses: dtolnay/rust-toolchain@miri
      - run: cargo miri setup
      - run: cd serde_core && cargo miri test --features rc,unstable
        env:
          MIRIFLAGS: -Zmiri-strict-provenance
      - run: cd test_suite && cargo miri test --features unstable
        env:
          MIRIFLAGS: -Zmiri-strict-provenance

  outdated:
    name: Outdated
    runs-on: ubuntu-latest
    if: github.event_name != 'pull_request'
    timeout-minutes: 45
    steps:
      - uses: actions/checkout@v7
      - uses: dtolnay/rust-toolchain@stable
      - uses: dtolnay/install@cargo-outdated
      - run: cargo outdated --workspace --exit-code 1

The same workflow, on Latchkey

Removes redundant runs and caps runaway jobs. Added and changed lines are highlighted.

name: CI
 
on:
  push:
  pull_request:
  workflow_dispatch:
  schedule: [cron: "40 1 * * *"]
 
permissions:
  contents: read
 
env:
  RUSTFLAGS: -Dwarnings
 
concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: true
 
jobs:
  test:
    name: Test suite
    runs-on: latchkey-small
    timeout-minutes: 45
    steps:
      - uses: actions/checkout@v7
      - uses: dtolnay/rust-toolchain@nightly
      - run: cd test_suite && cargo test --features unstable
      - uses: actions/upload-artifact@v7
        if: always()
        with:
          name: Cargo.lock
          path: Cargo.lock
        continue-on-error: true
 
  windows:
    name: Test suite (windows)
    runs-on: windows-latest
    timeout-minutes: 45
    steps:
      - uses: actions/checkout@v7
      - uses: dtolnay/rust-toolchain@nightly
      - run: cd test_suite && cargo test --features unstable -- --skip ui --exact
 
  stable:
    name: Rust ${{matrix.rust}}
    runs-on: latchkey-small
    strategy:
      fail-fast: false
      matrix:
        rust: [stable, beta]
    timeout-minutes: 45
    steps:
      - uses: actions/checkout@v7
      - uses: dtolnay/rust-toolchain@master
        with:
          toolchain: ${{matrix.rust}}
      - run: cd serde && cargo build --features rc
      - run: cd serde && cargo build --no-default-features
      - run: cd test_suite/no_std && cargo build
 
  nightly:
    name: Rust nightly${{matrix.os == 'windows' && ' (windows)' || ''}}
    runs-on: ${{matrix.os}}-latest
    strategy:
      fail-fast: false
      matrix:
        os: [ubuntu, windows]
    timeout-minutes: 45
    steps:
      - uses: actions/checkout@v7
      - uses: dtolnay/rust-toolchain@nightly
      - run: cd serde && cargo build
      - run: cd serde && cargo build --no-default-features
      - run: cd serde && cargo build --no-default-features --features alloc
      - run: cd serde && cargo build --no-default-features --features rc,alloc
      - run: cd serde && cargo build --no-default-features --features unstable
      - run: cd serde_core && cargo test --features rc,unstable
      - run: cd test_suite/no_std && cargo build
        if: matrix.os != 'windows'
      - run: cd serde_derive && cargo check --tests
        env:
          RUSTFLAGS: --cfg exhaustive ${{env.RUSTFLAGS}}
        if: matrix.os != 'windows'
 
  build:
    name: Rust ${{matrix.rust}}
    runs-on: latchkey-small
    strategy:
      fail-fast: false
      matrix:
        rust: [1.56.0, 1.60.0]
    timeout-minutes: 45
    steps:
      - uses: actions/checkout@v7
      - uses: dtolnay/rust-toolchain@master
        with:
          toolchain: ${{matrix.rust}}
      - run: sed -i '/"test_suite"/d' Cargo.toml
      - run: cd serde && cargo build --features rc
      - run: cd serde && cargo build --no-default-features
      - run: cd serde && cargo build --no-default-features --features alloc
      - run: cd serde && cargo build
 
  derive:
    name: Rust 1.71.0
    runs-on: latchkey-small
    timeout-minutes: 45
    steps:
      - uses: actions/checkout@v7
      - uses: dtolnay/rust-toolchain@1.71.0
      - run: |
          sed -i 's/proc-macro2 = { workspace = true/proc-macro2 = { version = "1"/' serde_derive*/Cargo.toml
          sed -i 's/quote = { workspace = true/quote = { version = "1"/' serde_derive*/Cargo.toml
          sed -i 's/syn = { workspace = true/syn = { version = "2"/' serde_derive*/Cargo.toml
      - run: cd serde && cargo check --no-default-features
      - run: cd serde && cargo check
      - run: cd serde_derive && cargo check
 
  minimal:
    name: Minimal versions
    runs-on: latchkey-small
    timeout-minutes: 45
    steps:
      - uses: actions/checkout@v7
      - uses: dtolnay/rust-toolchain@nightly
      - run: cargo generate-lockfile -Z minimal-versions
      - run: cargo check --locked --workspace
 
  doc:
    name: Documentation
    runs-on: latchkey-small
    timeout-minutes: 45
    env:
      RUSTDOCFLAGS: -Dwarnings
    steps:
      - uses: actions/checkout@v7
      - uses: dtolnay/rust-toolchain@nightly
      - uses: dtolnay/install@cargo-docs-rs
      - run: cargo docs-rs -p serde
      - run: cargo docs-rs -p serde_core
      - run: cargo docs-rs -p serde_derive
      - run: cargo docs-rs -p serde_derive_internals
 
  clippy:
    name: Clippy
    runs-on: latchkey-small
    if: github.event_name != 'pull_request'
    timeout-minutes: 45
    steps:
      - uses: actions/checkout@v7
      - uses: dtolnay/rust-toolchain@clippy
      - run: cd serde && cargo clippy --features rc,unstable -- -Dclippy::all -Dclippy::pedantic
      - run: cd serde_core && cargo clippy --features rc,unstable -- -Dclippy::all -Dclippy::pedantic
      - run: cd serde_derive && cargo clippy -- -Dclippy::all -Dclippy::pedantic
      - run: cd serde_derive_internals && cargo clippy -- -Dclippy::all -Dclippy::pedantic
      - run: cd test_suite && cargo clippy --tests --features unstable -- -Dclippy::all -Dclippy::pedantic
      - run: cd test_suite/no_std && cargo clippy -- -Dclippy::all -Dclippy::pedantic
 
  miri:
    name: Miri
    runs-on: latchkey-small
    timeout-minutes: 45
    steps:
      - uses: actions/checkout@v7
      - uses: dtolnay/rust-toolchain@miri
      - run: cargo miri setup
      - run: cd serde_core && cargo miri test --features rc,unstable
        env:
          MIRIFLAGS: -Zmiri-strict-provenance
      - run: cd test_suite && cargo miri test --features unstable
        env:
          MIRIFLAGS: -Zmiri-strict-provenance
 
  outdated:
    name: Outdated
    runs-on: latchkey-small
    if: github.event_name != 'pull_request'
    timeout-minutes: 45
    steps:
      - uses: actions/checkout@v7
      - uses: dtolnay/rust-toolchain@stable
      - uses: dtolnay/install@cargo-outdated
      - run: cargo outdated --workspace --exit-code 1

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.

2 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 11 jobs (14 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 actions/upload-artifact