Hi — I'm Jon.

I'm a senior/staff product engineer, educator, and author of two Node.js books with Manning and O'Reilly. I build AI-powered consumer products and the platforms behind them: at Meta I led UI architecture and the 8M+-user rollout of Meta AI on Quest, and earlier led messaging and ads infrastructure for Messenger. Before that I built ML-backed analytics products at Bloomberg.

Today I'm building agentic healthcare software at Marlow, and I care about the same things I always have: setting clear technical direction, shipping systems that hold up at scale, and making complex ideas easier to understand through teaching, writing, and mentoring.

I also run Hacky Apps, where I consult on engineering, product, and custom application development. See my portfolio for the full picture.

Elsewhere — podcast (JavaScript), Twitch: Node & web apps, Twitch: APIs.