Forkbench for Aider
The Mac terminal built for Aider
Aider is an open-source terminal coding agent that pairs with you in your git repository and commits each change it makes.
Forkbench is a Mac app for running Aider where the model keys it needs are used by the command and never handed to the agent, and a Thread can be locked to its folders by the macOS kernel. It gets a real login shell with a live git panel bound to that tab, so you can see every change Aider makes as it makes it.
What breaks in a plain terminal
Aider commits as it goes, which is a genuine strength and also the thing that makes people nervous. In a plain terminal you find out what it did by running git log after the fact, on whatever branch you happened to be on. Run two Aider sessions and they are committing to the same working tree at the same time. And because Aider talks to whichever model provider you configure, its API key has to live somewhere the process can read, which usually means your shell.
How Forkbench runs Aider
Model keys it can use and never read
Store the provider key in Vault. It reaches the command that needs it and stays out of your shell profile and out of anything else running on the machine. Vault is part of Pro.
Folders it cannot wander out of
Lock a Thread to the folders the job is about. Every shell in it starts under a macOS Seatbelt profile that the kernel enforces and every process inherits, including build scripts and a dependency's install hook, so a read or a delete outside them is refused rather than discouraged. Builds still run, paths still resolve, and the network is untouched.
A git panel that never lies
The panel always reflects the tab you are focused on, with per-hunk staging next to the CLI, so you can see what Aider committed without leaving the terminal. Forkbench never merges, rebases or changes your git on its own.
Its own branch, in one click
A new branch on a fresh worktree from the git panel keeps Aider's commits off your working branch, and lets a second session run without the two of them writing to the same tree.
A brief it reads once
Notebooks hold your conventions and decisions, granted per Thread, so the same context is available to Aider and to any other agent in that Thread.
Work that outlives the session
The board keeps the plan, the progress notes and the blockers on disk, so closing the pane does not lose what was decided.
Getting Aider running
- 1Open a Thread on your repo and run aider in a tab.
- 2Click once in the git panel to put it on a fresh worktree, so its commits stay off your working branch.
- 3Store your model provider key in Vault and grant it to the Thread, so it never has to sit in your shell profile.
- 4Watch the git panel as Aider commits, and stage or review per hunk without leaving the terminal.
- 5Merge when you are satisfied, in your own git client. Forkbench deliberately will not merge or rebase for you.
Aider questions
Does Aider run normally inside Forkbench?
Yes. Each tab is a real login shell, so aider behaves exactly as it does in any terminal, with your config, aliases and model settings unchanged.
How do I keep Aider's commits off my working branch?
Give its tab a fresh worktree from the git panel, which is one click. Aider then commits on its own branch in its own directory, and you merge it yourself when you are satisfied. Forkbench never merges or rebases on its own.
Can I run two Aider sessions at once?
Yes, each in its own tab on its own worktree so they never write to the same working tree. If you give the Thread an objective they also share a board, claiming tasks so neither duplicates the other's work.
Can Aider read my model provider key directly?
Yes, if it is in a .env file or your shell environment, because Aider has the same filesystem access you do. Store it in Vault instead and it reaches only the command that needs it, so Aider never has to hold the raw value to run.
What does it cost to run Aider in Forkbench?
Nothing extra for the agent. Aider bills through whichever model provider you point it at, and Forkbench never meters requests. The terminal, your notebooks and a board on every Thread are free. Vault and running more than one agent on the same board are Pro, and every account starts with 30 days of it without a card.
Running something else?
Forkbench is agent-agnostic, so any CLI agent runs in a tab. These have a page of their own: