Get Yellowhammer
Download Yellowhammer for macOS. The app and itsyh engine ship together.
Mac and local environment
- Use the macOS account that will run Nights to install and authenticate your tools.
- Install git 2.38 or later and Orca ADE. Setup looks for the
orcaexecutable on the PATH used by scheduled jobs. - Keep local checkouts of your working repositories and specification available, with space for Orca Worktrees and build output.
- Keep the Mac awake, signed in, and able to reach Linear, GitHub, and your coding agent service during unattended work. The app itself can be quit. See scheduling for timing and sleep behavior.
Connected services
Linear: use a workspace with a Linear project for the product, or a team where setup can create one. A workspace admin must approve Yellowhammer’s app installation. You can install as an admin on this Mac or send an approval link to an admin. You do not have to be the admin yourself. Select your own human Linear user as the Operator identity so issues needing a decision can be assigned to you. GitHub: prepare access to every working repository. Yellowhammer can use the activegh account or a named GitHub token stored in your login Keychain. The connection must be able to push and open pull requests in the repositories it serves. Connect GitHub explains how to check the Project’s repository access.
Agent access
The current adapters supportclaude, codex, and agy. Install and authenticate the CLI you intend to use, then declare it in Settings → Agent CLIs and give it a route in Base Routing Table. Run Probe Now before relying on it unattended. A declaration alone does not run a Probe.
A Probe reports the installed CLI version and compatibility findings. Read a failed finding and its reason rather than assuming an installed CLI is ready. See Connect Orca and agent CLIs.