Michael Haddon
Software engineer | Go, languages & infrastructure
I build:
- interpreters and compilers
- software and developer tools
- systems that stay up
- Go services
- infrastructure that teams rely on
Notable projects include:
- Pipit, an open-source Go interpreter
- Piko, the Go framework that renders this page
- The Replay Lattice, a type system for floating-point reproducibility
- maintaining the Dutch national ports infrastructure
- an Audi telemetry platform on 400+ servers

Based in
Jersey, Channel Islands
Exploring
Languages, execution and reproducibility
Currently building
Floatyboat, a dataflow language and compiler
Daily driving
Linux (Fedora), since the age of 18
Twenty years of building,
for the love of the game
I've been writing software since I was twelve. Games first, then websites, then the companies and tools around them. At heart I'm a software engineer, programming is the thing I'd do for fun, and mostly do.
For the last decade I've also built and run the infrastructure under other people's products, working with Kubernetes and cloud services and keeping them reliable. That has meant fintechs, the Dutch national ports, an Audi data platform and a run of consultancies. I like owning the whole picture and being the person who still understands it, end to end, at 3am.
About five years ago I started Piko. Its templating system got me into lexers, then an interpreter called Pipit grew out of it. These days I’m also working on Floatyboat, a language and compiler, and writing about what I learn along the way.
The stack I reach for
Things I've made and run
Tools & independent work
The web framework my wife and I kept rebuilding for client after client, folded into one binary. It powers a lot of the client work I ship and renders this very page, the house and the CV you can download. Server-side rendering, single-file components, its own PDF engine, no build pipeline the size of a small moon.
An interpreter for the Go programming language: run Go like a scripting language, no compile step, straight from source. It began inside Piko, from wanting a faster feedback loop without leaving Go. Now a separate bytecode compiler and runtime, open source under Apache 2.0.
Currently, I’m also building Floatyboat, an unreleased dataflow language and compiler.
More about the projectsThe studio my wife and I have run since 2022, and the home for the open-source tools I build: Piko, Pipit and the rest. Our projects grow out of practical work and a shared curiosity about how software is made.

Thinking out loud
How software and computers work, things I’m building, and the occasional marathon live stream.
My video channels
A few things I’ve been working out
Writing, research, and the occasional diagram.
Proof-led development
Linters, research papers and an AI-written Coq model help me check the work. Exploring that model found failures in Pipit's memory reuse that my tests had missed.
Pipit is leaving the nest
What makes an extracted interpreter independent of its original framework?
Joining the Jev hype
I give Jev a deliberately broken application and a lot of small questions. For something answering yes or no, it finds more than I expected.
AI is making me a less lazy tester
AI makes tests easier to write, and larger code changes make me rely on them more. Regression results give me outcomes I can inspect and preserve.
Convincing myself to like sum types
Coming from Go and C, sum types aren't something I naturally reach for. Floatyboat's compiler is giving me a reason to reconsider.
The invention nobody bothered to claim
I want one citation for the way my code adds numbers. A 1964 textbook, a Soviet proof and a missing IBM report make that surprisingly difficult.
Say hello!
I enjoy talking about languages, runtimes, and the things underneath software.
Have a question or something interesting to share? Get in touch.





