Aider

Free

aider.chat

Command-line AI pair programming tool editing code across multiple files directly in your Git repository with automated commits.

About Aider

Aider is a state-of-the-art open-source AI pair programming tool that operates directly inside your terminal command line. Designed for experienced software engineers who want to build features at accelerated speeds, Aider pairs with developers to edit code across multiple files, fix complex bugs, and write unit tests directly in live Git repositories.

The tool maintains a concise map of your entire Git codebase using Tree-sitter abstract syntax trees, allowing it to understand architectural relationships across dozens of files without exceeding model context windows. Whenever Aider modifies your code, it automatically writes a descriptive, sensible Git commit message and stages the commit, providing a clear history of every AI contribution.

Aider is completely free and open-source software under the Apache 2.0 license, installed via Python's package manager (`pip install aider-chat`). It connects with leading commercial models including Claude 3.5 Sonnet, GPT-4o, and DeepSeek, as well as local models running via Ollama.

Key Features

Core capabilities and technical highlights of Aider

Repository mapping engine utilizing Tree-sitter to give models a structural understanding of your entire codebase.

Multi-file code editing capabilities coordinating simultaneous refactoring across multiple source files.

Automated Git commit generation creating clean, descriptive commit messages for every applied code change.

Flexible model compatibility supporting Claude 3.5 Sonnet, GPT-4o, DeepSeek, and local Ollama models.

Popular Use Cases

How teams, developers, and creators get value from Aider

1Build complex software features across multiple interconnected files directly from terminal prompts.

2Ask the AI to locate and fix obscure bugs across your codebase with automated Git commit tracking.

3Generate comprehensive unit and integration test suites for existing functions and run them automatically.

4Refactor legacy code architectures while maintaining full version control auditability via automatic commits.

Frequently Asked Questions

Common questions and answers regarding Aider

Is Aider free?

Yes, Aider is 100% free and open-source software under the Apache 2.0 license, though users supply their own API keys for cloud model providers.

How does Aider edit code in a repository?

Aider analyzes your repository map, writes precise code diffs, edits the local files on disk, and automatically creates a Git commit with a descriptive message.

Can Aider edit multiple files at once?

Yes, Aider excels at coordinating changes across multiple files, updating function declarations, imports, and test suites in a single prompt.

Which models work best with Aider?

Aider is recognized for achieving top scores on the SWE-bench benchmark when paired with Claude 3.5 Sonnet, GPT-4o, and DeepSeek Coder.

Does Aider work with local models?

Yes, Aider can connect to local models running through Ollama or LM Studio, allowing developers to pair program offline.