Aider is a free, open-source CLI tool that lets developers collaborate with LLMs directly in the terminal to write, edit, debug, and refactor code across existing repositories. It automatically stages and commits changes via Git, runs linters and tests, and supports voice input. It works with Claude, GPT-4o, DeepSeek, and local models. Ranked highly on coding benchmarks, it is a leading open-source alternative to commercial coding assistants. Key features: - Automatic Git commits for every AI-generated code change - Supports 100+ languages and most major LLM providers - Runs linters and tests automatically; can self-fix detected errors - Voice input mode for hands-free coding requests - Can include images and web pages as context in chat
Free and open-source. Users pay only their own LLM API costs (typically $30-$60/month in API usage).