Aider
Aider is an open-source AI pair-programming tool that lets you edit and extend code in your terminal with LLM assistance.
About
Aider runs in your terminal and connects to your local git repository, letting you ask an LLM to add features, fix bugs, refactor code, or update documentation across multiple files at once. It works with leading models including Claude Sonnet, GPT-4o, and DeepSeek, and supports dozens of languages from Python and JavaScript to Rust and Go. Every code change is automatically committed with a descriptive git message so you can review, diff, or undo AI edits using standard git tools. Aider itself is free and open source; you supply your own API key for whichever model you choose.