aider

Aider is a terminal-based AI pair programmer that edits your actual codebase. Not a chatbot that spits out snippets you copy-paste. You point it at your repo, tell it what to build or fix, and it writes the code directly into your files with proper git commits. It builds a map of your entire codebase so it understands how everything connects, even in large projects.

Works with Claude, GPT-4o, DeepSeek, o3-mini, local models, basically anything. Supports 100+ languages. Has voice input, image context, linting integration, and IDE watch mode. Alternatives like Continue and Cursor offer similar AI coding but lock you into their editor. GitHub Copilot stays in VS Code's world. Aider stays in the terminal and works with whatever editor you already use.

The catch: you bring your own API keys and pay for tokens directly. Heavy usage with frontier models gets expensive fast, and the terminal-first UX has a learning curve if you are not already living in the command line.