aider.el : aider (AI Pair Programming) Inside Emacs

Introduction

Do you like the AI features of Cursor AI Code Editor, but prefer to stay within Emacs?
Aider is good AI pair programming in the terminal.
aider.el provides an interactive interface to communicate with Aider in emacs.
- Most of the Elisp code in this repository was generated by aider / aider.el.

Why Use aider.el in Emacs?

Pop-up Menu: No need to remember commands. (aider-transient-menu)

Git Repository-Specific aider Sessions in Emacs: Automatically identify the Git repository of the current file and create a new aider session for it. Multiple aider sessions can exist for different Git repositories.
More ways to add files to aider buffer
- Add current buffer file: (aider-add-current-file)
- Add all buffers in current window: (aider-add-files-in-current-window)
- Batch add files from dired buffer (aider-batch-add-dired-marked-files): Add multiple Dired marked files to the Aider buffer.
Region-Based Explain / Refactor Support
- Explain: (aider-region-explain): You can select a region (e.g., a code block) in a file and ask aider to explain it.
- Refactor: (aider-region-refactor): Ask aider to refactor it given your input instruction
And More: Add your own Elisp functions to support your use case. You can certainly ask aider / aider.el to do that.

Installation

Vanilla Emacs Installation

Install aider
Install the dependency Transient using your package manager.
Install aider.el with the following code:

(use-package aider
  :straight (:host github :repo "tninja/aider.el" :files ("aider.el"))
  :config
  (setq aider-args '("--model" "gpt-4o-mini"))
  (setenv "OPENAI_API_KEY" <your-openai-api-key>)
  ;; Optional: Set a key binding for the transient menu
  (global-set-key (kbd "C-c a") 'aider-transient-menu))

Doom Installation and Configuration

Add the following code to your doom/packages.el

(package! aider :recipe (:host github :repo "tninja/aider.el" :files ("*.el")))

Adjust and add the following code to your doom/config.el

(use-package aider
  :config
  (setq aider-args '("--model" "gpt-4o-mini")))

The aider prefix is “l”.

Start and open the aider buffer: [SPC] l o
Add the current file with [SPC] l a c

Optional

You might want to try aider-helm.el. That file added support of command history and completion from helm.
If you enjoy writing aider command in a separate file and send them to aider session, just like working on python or R script and send code block into REPL, you might want to try aider-minor-mode. It by default bind C-c C-n to send current line to aider session, and C-c C-c to send current region to aider session.
- To automatically enable aider-minor-mode to any file with aider inside filename

(add-hook 'find-file-hook
          (lambda ()
            (when (and (buffer-file-name)
                       (string-match-p "aider" (buffer-file-name)))
              (aider-minor-mode 1))))

Screenshot

In the above screenshot, aider was asked to generate an aider-help function and add the corresponding entry to the menu (top right window).
aider received the command and generated the commit for it (bottom left).

Example Application Written with aider.el

Other Emacs AI coding tool

Inspired by, and Thanks to:
- ancilla.el: AI Coding Assistant support code generation / code rewrite / discussion
- chatgpt-shell: ChatGPT and DALL-E Emacs shells + Org Babel
- copilot.el: Emacs plugin for GitHub Copilot