fallow

Fallow Plugin

Codebase analyzer for TypeScript and JavaScript. Finds unused code, circular dependencies, code duplication, and complexity hotspots. Rust-native, sub-second.

Commands

All Analyses

• fallow — Run dead-code, dupes, and health analyses

Dead Code

• fallow deadcode scan — Find unused files, exports, dependencies, types

Duplication

• fallow dupes scan — Find copy-pasted code blocks

Complexity

• fallow health analyze — Analyze complexity hotspots

Audit (PR Quality Gate)

• fallow audit check — Quality gate for AI-generated code and PRs

Auto-fix

• fallow fix apply — Auto-remove dead exports and deps

Score (Quick Health)

• fallow score run — Get health score, hotspots, and refactoring targets in one call

CI Gate

• fallow ci gate — CI quality gate with non-zero exit on new issues, SARIF output

Usage Examples

Run all analyses:

fallow

Dead code detection:

fallow dead-code
fallow dead-code --unused-exports
fallow dead-code --circular-deps
fallow dead-code --boundary-violations
fallow dead-code --changed-since main

Duplication scan:

fallow dupes
fallow dupes --mode semantic
fallow dupes --trace src/utils.ts:42

Health/check complexity:

fallow health --score
fallow health --top 20
fallow health --hotspots

Audit PR:

fallow audit
fallow audit --base main
fallow audit --format json

Auto-fix preview:

fallow fix --dry-run

Quick health score:

fallow score run
fallow score run --format badge

CI quality gate:

fallow ci gate
fallow ci gate --base main --format sarif
fallow ci gate --min-score 70

Installation

cargo install fallow-cli

Or via npm:

npm install -g fallow
npx fallow

Key Features

• Sub-second analysis (Rust-native)
• Zero config needed
• 90 framework plugins (Next.js, Vite, Jest, etc.)
• Dead code: unused files, exports, deps, circular deps
• Duplication detection across entire codebase
• Complexity analysis with refactoring targets
• PR quality gate with pass/warn/fail verdict
• Multiple output formats (JSON, SARIF, markdown)
• CI/CD integration (GitHub Actions, GitLab CI)