About

I'm John Cairns, a software engineer in Chicago.

I build distributed systems in Rust at Open Standard. I write smart contracts for Ethereum and Solana. My background in physics and systems programming grounds my work. I appreciate the balance of art and science, and a considered approach in all things.

This blog covers code, maps, and everything I am interested in. My code is on GitHub.

What you'll find here

PlayMMIX Run, Step, Next and Share controls above an MMIX assembly editor

Code and computing

Checksmix, MMIX in the browser, everything engineering and how to build on Ethereum.

PlayMMIX · A Fix is not a Plan · all code posts

Spanish and Muslim naval and land movements around Gibraltar, 1340

Maps and history

I'm proud to be a part of six military-history books by Brian Todd Carey. I illustrated the regional maps.

Gibraltar, 1340 · Cartography & Books · all history posts

Beyond the machine

A proud husband and father of three. I love my kids' sports, soccer and volleyball. I'm an avid photographer, and when I'm not working I'm with my children.

Find me on-chain

My ENS name is jac1828.eth, a human-readable name on Ethereum. My PGP key has the fingerprint FD311EE84C8321C3E93C1E639028C4309ACCEB9B.