Aider

What it's good for

• 1

  Editing code across multiple files from the terminal without leaving the shell

• 2

  Keeping a clean git history where every AI change is its own reviewable commit

• 3

  Working with whichever model is cheapest or best today by swapping the API key

• 4

  Running fully local with Ollama when code cannot leave the machine

• 5

  Scripting AI edits into a repo as part of a larger workflow

Pricing

• Aider

  Open source, Apache 2.0

  Free

• Model usage

  You pay your model provider directly

  BYO key

How to use it

Install with `pip install aider-chat`, set the API key for your model of choice (or point it at a local Ollama model), and run `aider` inside a git repo. Tell it what to change in plain English; it edits the relevant files and commits each change so you can review the diff or roll back cleanly. Add files to the chat context explicitly to keep the model focused. The repo is Aider-AI/aider on GitHub if you want to read the source or file issues.

Pros & cons

Frequently asked questions

• Is Aider free?

  Aider itself is free and open source under the Apache 2.0 license. You bring your own API key and pay your model provider directly (Claude, GPT, DeepSeek, Gemini, or a local Ollama model), so your only cost is the model usage. Running fully local with Ollama can make it free end to end.

• Aider vs Cursor: what is the difference?

  Cursor is a full GUI editor with AI built in. Aider lives in your terminal instead, reading your git repo and committing each change as its own reviewable commit. If you find IDE-based AI tools heavy and prefer the shell, Aider is the lean alternative; if you want a graphical editor, Cursor fits better.

• Is Aider open source?

  Yes, under the Apache 2.0 license. The repo is Aider-AI/aider on GitHub, so you can read the source, file issues, or contribute. Being open source and bring-your-own-key is the whole point: nothing is locked behind a vendor.

• Which models does Aider work with?

  It is model-agnostic and bring-your-own-key, so it works with Claude, GPT, DeepSeek, Gemini, and local models through Ollama. You can swap to whichever model is cheapest or best on a given day just by changing the key.

• How do I install Aider?

  Run `pip install aider-chat`, set the API key for your chosen model (or point it at a local Ollama model), and run `aider` inside a git repo. Tell it what to change in plain English and it edits the relevant files, committing each change so you can review the diff or roll back.

More

• Aider docs
• GitHub repo

Alternatives to Aider

Other tools we'd consider for the same job.

• Cursor

  AI-first code editor. Chat with your codebase, auto-apply edits, and let the agent tackle multi-file refactors

• GitHub Copilot

  Inline AI autocomplete + agent mode inside VS Code, JetBrains, and the GitHub web editor. The category-defining incumbent

Other Code tools

• Cursor

  AI-first code editor. Chat with your codebase, auto-apply edits, and let the agent tackle multi-file refactors

• Devin

  Autonomous software engineer that plans, codes, runs commands, and ships a whole task without a human at the keyboard

• GitHub Copilot

  Inline AI autocomplete + agent mode inside VS Code, JetBrains, and the GitHub web editor. The category-defining incumbent

• v0 by Vercel

  Generate React / Next.js UIs from a prompt. Outputs production-ready shadcn-style components you can copy straight into a repo