About

Don Stewart

2022: I’m a software engineer in Sydney working on the Glean code search platform.

I spent the 2000s completing a PhD in computer science at UNSW in Sydney,  developing new approaches to dynamic extension and hot swapping features for the Haskell programming language. I also worked on compiler optimizations for GHC, leading to “stream fusion” (parodied in this comic strip). At the same time I squeezed in a lot of open source hacking, and co-wrote “Real World Haskell”, a book on Haskell programming.

I then worked at Galois, Inc. in Portland, Oregon, for four years, as a researcher doing Haskell programming for high assurance systems — particularly using DSLs and compiler technology.

I moved to New York in 2011 to build trading systems in Haskell for Standard Chartered Bank, with stints in Singapore and Hong Kong, eventually landing in London. Over 6 years I built a team of 40 Haskell devs writing code for all parts of the financial markets business at SCB.

In 2017 I joined Facebook as engineering manager for the Infer static analysis team. I then managed the Testing + Verification (T+V) org within Facebook, from 2017-2020, growing it to 5 teams and around 50 engineers, spanning everything from testing to type systems and static analysis.

In 2020, I quit management and returned to a software engineering role, in Testing & Verification, at Facebook London, 2020-21. I’m now based in Sydney, working on the Glean code, in the Programming Languages & Runtime team at Meta.

I co-authored a book about Haskell, and a popular window manager for unix. I’ve written some papers and regularly give talks on programming language topics.

Contact me

• Email: dons00 (at) gmail.com
• Mastodon: donsbot@aus.social
• Twitter: @donsbot (defunct)
• You can find me on LinkedIn.

Older stuff:

• I was dons on the #haskell IRC channel, Reddit and YCombinator
• I formerly enjoyed anwering questions on Stack Overflow

Finally, I work on a lot of open source projects.