Open-source sustainability linter for GitHub Actions

Make your CI/CD
pipeline greener

CI/CD pipelines run millions of times daily, consuming significant compute and energy. Most workflows are written without considering their environmental footprint. Small inefficiencies compound at scale — and there’s been no standard tooling to catch them. Until now.

Explore Guidelines Get the tool
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Millions
of CI runs happen daily worldwide
Unchecked
Most workflows ignore environmental impact
Compounding
Small inefficiencies multiply at scale
Fixable
Simple changes make a real difference

Sustainability Rules

Guidelines for greener workflows

Each rule targets a specific source of waste in GitHub Actions. Follow them to cut unnecessary compute, reduce energy use, and ship with a lighter footprint.

The Tool

Meet suslint

An open-source CLI that scans your GitHub Actions workflow YAML files and flags sustainability issues — so you can fix them before they ship.

suslint

Point it at your workflow files and get instant feedback. Each issue links back to a sustainability guideline with a clear fix.

  • Scans single files, directories, or glob patterns
  • JSON output for CI integration
  • Select or ignore specific rules with flags
  • Zero config — works out of the box
  • Cross-platform: Linux, macOS, Windows
Get Started View on GitHub
Terminal
$
 
.github/workflows/ci.yml
  5:3  warning  job 'build' has no timeout-minutes  SUS001
  3:3  warning  Workflow triggers on push to all branches  SUS002
 
───
Found 2 warnings in 1 file
 
$
How to install
# Option 1 — Download a prebuilt binary (recommended) # 1. Download from GitHub Releases # Choose the correct file for your system: # Linux (x86_64): suslint-x86_64-linux # Linux (ARM): suslint-aarch64-linux # macOS (Intel): suslint-x86_64-darwin # macOS (Apple Silicon): suslint-aarch64-darwin # Windows: suslint-x86_64-windows.exe # 2. Make executable (Linux/macOS) chmod +x suslint-* # 3. Move to PATH (optional) sudo mv suslint-* /usr/local/bin/suslint # Run the tool suslint
# Option 2 — Install with pip (Python 3.11+ required) # Clone the repository git clone https://github.com/KaspervanM/sustainable-gh-workflow-linter.git cd sustainable-gh-workflow-linter # Install globally sudo pip install . # OR install locally pip install --user . # OR use a virtual environment python -m venv .venv source .venv/bin/activate python -m pip install . # Run the tool suslint
# Option 3 — Use Nix # Run without installing nix run github:KaspervanM/sustainable-gh-workflow-linter # Install permanently nix profile install github:KaspervanM/sustainable-gh-workflow-linter # Build locally nix build github:KaspervanM/sustainable-gh-workflow-linter

Verify the installation
# Verify installation suslint --help # If using Nix nix run github:KaspervanM/sustainable-gh-workflow-linter -- --help