Rebuilding a Siri-style assistant over the weekend with Jev
The author fine-tuned Laya, an open-weight alternative to Jev, on 10,000 intent samples so it decides on-device in about 100ms whether to trigger a timer, reminder or music, with the real bottleneck coming from Apple's own APIs.
Apple pays Google $1 billion a year for Siri. I rebuilt it over the weekend with Jev. Meet Jav, an assistant that makes decisions faster thanks to Laya, the open-weight alternative to Jev, running entirely on-device with CoreAI. I fine-tuned it on 10,000 intent samples covering around 100 different actions an iPhone assistant might need to take. It takes a request and decides what should happen: timer, reminder, calendar event, music, weather... Laya makes the routing decision in around 100 ms. Surprisingly, the bottleneck comes from Apple's own Foundation Model and App Intents APIs. Decisions are solved, now let's make actions smarter and faster with another on device model.