codemod-gen

Codemod Generator

You need to replace a pattern across 500 files. Find and replace won't cut it. This tool generates AST-based codemods that safely transform your code at scale.

One command. Zero config. Just works.

Quick Start

npx ai-codemod "convert class components to functional"

What It Does

• Generates jscodeshift codemods for your specific transformation
• Handles complex patterns like class to function conversions
• Preserves formatting and comments
• Works across entire codebases

Usage Examples

# Class to functional components
npx ai-codemod "convert class components to functional"

# Modernize code
npx ai-codemod "replace lodash.get with optional chaining"

# API migrations
npx ai-codemod "migrate from moment to date-fns"

# Framework upgrades
npx ai-codemod "update React Router v5 to v6"

Best Practices

• Test on a branch first - always run codemods on a fresh branch
• Review the diff - spot check that transformations are correct
• Run incrementally - do one file type at a time
• Keep the codemod - save it for future use

When to Use This

• Major framework or library upgrades
• Enforcing new code patterns across the codebase
• Deprecating old APIs in favor of new ones
• Standardizing code style at scale

Part of the LXGIC Dev Toolkit

This is one of 110+ free developer tools built by LXGIC Studios. No paywalls, no sign-ups, no API keys on free tiers. Just tools that work.

Find more:

• GitHub: https://github.com/LXGIC-Studios
• Twitter: https://x.com/lxgicstudios
• Substack: https://lxgicstudios.substack.com
• Website: https://lxgicstudios.com

Requirements

No install needed. Just run with npx. Node.js 18+ recommended. Needs OPENAI_API_KEY environment variable.

npx ai-codemod --help

How It Works

Takes your plain English description of the transformation and generates a jscodeshift codemod script. The AI understands AST manipulation and outputs a codemod you can run with jscodeshift or babel.

License

MIT. Free forever. Use it however you want.