Let It Brew: keeping the Mac awake for coding agents

I used Caffeine, Amphetamine and the pmset command to keep my Mac awake while coding agents worked, but none of them knew what the agents were doing. If I left the Mac awake too long the battery died, and if I didn't leave it awake long enough it went to sleep and cut my agent off halfway through a task. I needed something that tracked my Claude Code and Codex sessions, so I built Let It Brew. Keeping the Mac awake with the lid closed was part of it from the start, because I used to leave the lid slightly open and my cat, Dusk, kept shutting it.

Let It Brew is a native macOS menu-bar app written in Swift. It listens to each agent's lifecycle events, so it knows when a session is working, waiting on a question or done, and it keeps the Mac awake only while something is working. It lets the Mac sleep again as soon as the work stops, an agent asks a question, the battery drops to a level you set or the Mac gets too hot, and nothing about your sessions leaves the Mac.

I shared it with some friends, and they asked for GitHub Copilot CLI, OpenCode and Pi support, so I added those too. It's free and open source and I'm still maintaining it. You can get it from letitbrew.app.