Ninebrains

Ninebrains runs several coding agents side by side. Each one works in a lane: its own git worktree and branch, its own terminal, an editor and a browser. A central Brain holds the plan as a graph of jobs and hands ready jobs to idle lanes. Verification gates check the work with a second, independent run before it counts as done.

The name comes from the octopus: one central brain, plus a small brain in each of its eight arms.

Ninebrains is free and open source (Apache-2.0), and a fork of Emdash by General Action. It launches the claude and codex CLIs you already have, under your own login. It never handles your credentials.

Status: pre-release. v0.1 is being built now, and builds are unsigned.

Start here

• Getting started: install, add a project, open your first lanes.
• Install from source, first run, and how to verify and open a download.
• Lanes: the grid, status lights, sleep and maximize.
• Brain and jobs: how work is planned, routed and reported.
• Planner: draw the plan as a graph and run it.
• Verification gates: what checks the work, and the rigor settings.
• Packs: coding, SEO and research bundles, and what the SEO pack sends where.
• Unattended runs: budgets, the STOP switch, and what never runs on its own.
• Accounts: several Claude Code or Codex logins.
• Models: routing lanes and subagents to cheaper models, and what SEC-39 and SEC-41 protect against.
• Everyday workflow: tasks, the editor, diffs, pull requests, MCP, skills and automations.
• Keyboard shortcuts.
• Configuration and files outside the data folder: settings, environment variables and file locations.
• Security overview, security policy and threat model.
• Troubleshooting.
• Architecture and contributing, for contributors.

What Ninebrains adds

On top of Claude Code, which it runs unchanged:

• several agents on screen at once, each in its own worktree;
• a shared plan with dependencies, and a mailbox between agents;
• an independent check before any work counts as done;
• budgets and a STOP switch for runs nobody is watching.

On top of Emdash, which it is built on:

• the 2×2 lane grid across worktrees;
• the Brain, the planner, the gates and the packs;
• no telemetry endpoint, no hosted account, and no update feed until builds are signed.