A selection of products, open-source libraries, and experiments I’ve worked on.

At Stripe

  • Stripe Projects: Tools for developers and AI agents to provision services and manage their billing from the command line.
  • Stripe Billing: Subscription and recurring billing infrastructure. I spoke about our work refactoring its billing engine using Domain Driven Design at BOB 2026.

Side projects

  • Board: A collaborative whiteboard for sketching and sharing ideas with others in real time.
  • jot away: A simple place for daily notes and todos.
  • vindex: Semantic video search that lets you find moments in a video using natural language. I wrote about building its processing pipeline with Temporal.
  • Supportpage.io: A help desk with semantic search across support articles and AI-assisted replies to support tickets.

Earlier commercial work

  • Bahn-Buddy: A service I co-founded to help rail passengers claim compensation for delays. Sold to RightNow GmbH.
  • TramCloud: A company I co-founded to build tools for measuring and analyzing tram rail wear.
  • Checkpad MED: A mobile electronic patient record for hospital staff, which I worked on as a software engineer.
  • Factis: Software for data collection and reporting in health and social care, which I worked on as a software engineer.

Open source

  • Spock: A lightweight Haskell web framework with type-safe routing, sessions, and database pooling.
  • SuperRecord: Fast anonymous records and variants for Haskell. See the implementation write-up for the design and trade-offs.
  • dockercook: A build tool for managing Docker image layers and speeding up builds and deployment.
  • WebSocketServer: A C++ WebSocket server with Lua integration.

More of my work is available as Haskell packages on Hackage and repositories on GitHub.

Games and experiments

  • Manager’s Life: A multiplayer browser game I wrote in 2011. The hosted game is discontinued; its source is available on GitHub.
  • TribalWars LAN: A version of Tribal Wars for playing on a local network.

Other early projects include a ReTi simulator and the iOS game Bean Bouncer.