Quick Start

This guide gets you running Lien's four commands in under a minute.

Step 1: Install

npm install -g @liendev/lien

See Installation for prerequisites and the npx alternative if you'd rather not install globally.

Step 2: Run It

There's no setup wizard and nothing to configure. cd into a project and run any of the four commands — each one parses your working tree on the spot:

# Rank the functions riskiest to change
lien health

# Analyze complexity across the codebase
lien complexity

# Run deterministic signals over your uncommitted changes
lien review

# Flag NEW complexity threshold crossings before you commit
lien delta

No index, no wait

There's no first-run indexing step and no model to download. Every command parses fresh, so the numbers you see always match what's on disk right now.

Step 3: Try It on a Real Change

Make an edit, then run:

lien review

If your working tree has no changes against HEAD, review says so explicitly rather than printing an empty "all clear" report — pass --base <ref> to compare against something else (e.g. origin/main).

Before committing, run:

lien delta

It only fails when your changes push a function's complexity over a threshold it was under at HEAD — pre-existing complexity debt never fails the check.

Monorepo Support

Lien automatically detects and scans multiple ecosystems:

# Example monorepo structure
my-app/
  ├── src/                  # Node.js/TypeScript (auto-detected)
  └── backend/              # Laravel (auto-detected)

Lien scans your project structure and applies the right exclusions for each detected ecosystem, no configuration needed.

Troubleshooting

lien delta or lien review says "not a git repository"

delta and review both diff your working tree against a git ref, so they need to run inside a git repository. complexity and health don't — they just scan the files on disk.

Slow scans on very large codebases

• Lien automatically excludes node_modules, dist, and other build artifacts via ecosystem presets
• A scan is CPU-bound Tree-sitter parsing with no network step, so it's roughly linear in file count — see Performance for measured numbers

Next Steps

• Learn about per-project configuration (complexity thresholds only)
• Read about CLI Commands for the full flag reference