Plug in a USB keyboard or pair one over Bluetooth, and it plays the keys on screen: each note lights up and counts as played. While a beat plays, Yui sends MIDI clock so your drum machine keeps time.
The MVP is done and Yui is in alpha, open to anyone with an iPhone on iOS 26. Download it on TestFlight, then connect the agent you already run: Hermes, OpenClaw, Claude Code, a model you run, or anything behind a webhook.
Yui is open source under Apache 2.0. Star the repo, open an issue, or send a pull request.
Spare tokens on Claude or ChatGPT Codex? Your agent can pick a card off our backlog and open a pull request. Yui@home, like SETI@home.