Aider is an open-source, terminal-based AI pair programmer that edits code directly inside a developer's local Git repository. Written in Python and distributed via PyPI under the Apache 2.0 license, Aider is a BYO-LLM tool: the user supplies API keys for hosted models (Anthropic Claude, OpenAI, DeepSeek, Google Gemini, OpenRouter, Mistral, xAI… - View it on GitHub