Peter Wen

I'm a founder in San Francisco building software for accountants, which is a narrower thing to care about than it sounds and a deeper one than most people expect.

What I'm building

Tallyfor is automating tax — the unglamorous middle of the accounting stack, where a firm's actual leverage lives and where most tools give up.

Perch is an AI-native, agentic accounting platform.

Before that

I was a historian, a CPA, and the first US product hire at Xero. I've architected tax calculation engines and trial balance systems, which is how I learned that tax logic is one of the few remaining domains where the rules are written down, enormous, and still mostly encoded by hand.

Most of what I make is full-stack AI-pilled Clojure, on GCP, Firebase and Cloud Run.

Off the keyboard

I practice and teach yoga — I did my teacher training in San Francisco, in the Baptiste interpretation. I've been researching where the styles taught in America actually came from, and how yoga fits into the history of human movement. That turned into a project larger than I intended, which lives here — including Asana, in Parts, which composes pose names from 259 Sanskrit words rather than looking them up, so a pose does not have to be on a list to have a name. I also ride bikes.

Random stuff

Things that do not belong anywhere else.

Elsewhere

The best way to reach me is email.