workflow-development

name	workflow-development
description	Create, debug, and optimize GitHub Actions workflows with security best practices. USE THIS SKILL when user says "create workflow", "fix workflow", "workflow fails", "add CI", "reusable workflow", or needs help with GitHub Actions.
allowed-tools	["Bash","Read","Write","Edit","Glob","Grep"]

Workflow Development Skill

Design, debug, and optimize GitHub Actions workflows with security best practices.

Trigger Phrases

• "create a CI workflow"
• "add a release workflow"
• "my workflow is failing"
• "make this workflow reusable"
• "workflow security audit"
• "add [language] CI"

Security Requirements (Non-Negotiable)

SHA Pinning

# CORRECT
- uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # v6.0.1

# WRONG - Never use tags
- uses: actions/checkout@v4

Minimal Permissions

permissions:
  contents: read  # Start with minimum

# Only add what's needed:
# pull-requests: write  # For PR comments
# packages: write       # For container registry

Reusable Workflow Pattern

Caller (in project)

name: CI
on: [push, pull_request]

jobs:
  ci:
    uses: epicpast/.github/.github/workflows/reusable-ci-python.yml@main
    with:
      python-version: '3.12'
      coverage-threshold: 80
    secrets: inherit

Reusable Definition (in .github repo)

name: Reusable Python CI

on:
  workflow_call:
    inputs:
      python-version:
        required: false
        type: string
        default: '3.12'
      coverage-threshold:
        required: false
        type: number
        default: 80

permissions:
  contents: read

jobs:
  lint:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8
      - uses: epicpast/.github/actions/setup-python-uv@main
        with:
          python-version: ${{ inputs.python-version }}
      - run: uv run ruff check .

Available Reusable Workflows

Workflow	Purpose
reusable-ci-python.yml	Python with uv, ruff, pyright, pytest
reusable-ci-typescript.yml	TypeScript with pnpm, ESLint, Vitest
reusable-ci-go.yml	Go with golangci-lint
reusable-release.yml	Semantic release
reusable-security.yml	Gitleaks + dependency scanning

Composite Action Pattern

# action.yml
name: 'Setup Python with uv'
description: 'Install Python and uv with caching'

inputs:
  python-version:
    required: false
    default: '3.12'

runs:
  using: 'composite'
  steps:
    - uses: astral-sh/setup-uv@v4
      with:
        enable-cache: true
    - shell: bash
      run: uv python install ${{ inputs.python-version }}

Debugging Workflows

Common Failures

Error	Cause	Fix
"Resource not accessible"	Missing permission	Add to permissions:
Cache never hits	Wrong key	Check hashFiles path
Secrets unavailable	Wrong context	Use secrets: inherit
Workflow not triggered	Event mismatch	Check on: config

Debug Step

- name: Debug
  run: |
    echo "Event: ${{ github.event_name }}"
    echo "Ref: ${{ github.ref }}"
    echo "Actor: ${{ github.actor }}"

Performance Optimization

Caching

- uses: actions/cache@0c907a75c2c80ebcb7f088228285e798b750cf8f
  with:
    path: ~/.cache/uv
    key: ${{ runner.os }}-uv-${{ hashFiles('uv.lock') }}

Matrix Builds

strategy:
  fail-fast: false
  matrix:
    os: [ubuntu-latest, macos-latest]
    python: ['3.11', '3.12']

Concurrency

concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: true