I started writing this post because, for whatever reason, I keep forgetting what the difference is between a ring and a group, which is funny to me because I never forget the difference between a semiring and a semigroup – although other people do, because it’s quite easy to forget! So, I wanted a fast reference to the kinds of algebraic structures that I am most often dealing with in one way or another, usually because I’m writing Haskell (which has some reliance on terminology and structure from abstract algebra and category theory) or I’m trying to read a book about category theory and they keep talking about “groups.” Wikipedia, of course, defines all these structures, and that’s fine, but what I need in those times is more of a refresher than an in-depth explanation.

We recently ran across a strange higgs-bugson that manifested itself in a critical system that stores and distributes the firm’s trading activity data, called Gord. (A higgs-bugson is a bug that is reported in practice but difficult to reproduce, named for the Higgs boson, a particle which was theorized in the 1960s but only found in 2013.) In this post I’ll walk you through the process I took to debug it. I tried to write down relevant details as they came up, so see if you can guess what the bug is while reading along.

zb is a tool for reproducibly building software, similar to Bazel.
(See the comparison page if you’re curious to know the differences.)
When a software build process is reproducible,
it will produce the exact same output
when given the same inputs.
Reproducibility is a desirable property for a software build process to have:
it simplifies debugging,
it enables build speed-ups,
and it is essential for digital supply chain security.
However, reproducibility is a difficult goal to achieve.

In modern Java, the visitor pattern is no longer needed. Using sealed types and switches with pattern matching achieves the same goals with less code and less complexity.

I recently wrote about Async Pool, one of my favorite JavaScript / TypeScript helpers, and today I want to share an even simpler yet extremely useful utility

A somewhat compact implementation of the awk programming language

plainweb is a framework using HTMX, SQLite and TypeScript for less complexity and more joy.

This article presents the program earlyoom to prevent a Linux system to lock up in low memory situations.

Last year I finally decided to learn some Rust. The official book by Steve Klabnik and Carol Nichols is excellent, but even after reading it and working on some small code exercises, I felt that I …

From Erlang, to Elixir and now, GLEAM!?

I've been running NetBSD on a RockPro64 since NetBSD 10-BETA, and I'm still happy with it now with NetBSD 10-RELEASE. I'm always looking for hardware to hack NetBSD though, and I recently watched a FOSDEM 2024 video: NetBSD 10: Thirty years, still going strong!. The Pinebook Pro laptop was mentioned at one point, which has the same RockChip SoC as the RockPro64. That reminded me I'd been wanting to give this inexpensive ARM 64 laptop a try.