Hi there, this is Junsong. Welcome to my weblog.

I am a father of two, a life-long learner, a software engineer caring about quality work, and a human enjoying various forms of art.

My main interests in Computer Science lie in programming language theory (PLT) and large-scale systems. My favorite languages are OCaml and Racket.

My sweet spot in the tech stack is inside the OS and between servers. I have a track record scaling systems: at Meta, I worked on POSIX storage services in multi-region clusters and built FUSE clients deployed to millions of containers; later, I worked on routing infrastructure for the blob storage serving Facebook and Instagram photos and videos; at WeRide, I was the sole owner scaling the remote execution Buildbarn clusters to support 800 engineers with four 9s of availability.

Those years of firefighting production issues shaped how I reason about systems. Repeated exposure to failures in complex systems trained me to design systems defensively: the more I ask how a system can fail, the more stable the final system tend to be.

My favorite books:

• How to Solve it by George Pólya
• The Inner Game of Tennis: The Classic Guide to the Mental Side of Peak Performance by Gallwey, W. Timothy
• The Art of Doing Science and Engineering: Learning to Learn by Richard Hamming
• Understanding Comics: The Invisible Art by Scott McCloud

You can also find me at

• Goodreads
• GitHub