Automerge is a local-first sync engine for multiplayer apps that works offline, prevents conflicts, and runs fast.

Welcome to “stupid jj tricks”. Today, I’ll be taking you on a tour through many different jj configurations that I have collected while scouring the internet. Some of what I’ll show is original research or construction created by me personally, but a lot of these things are sourced from blog post, gists, GitHub issues, Reddit posts, Discord messages, and more.

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.

Things we wish we didn't know

I just learned that
you can use it to review a git commit like this and I thought that was really
cool.

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.

I have been using IntelliJ Idea at work for a decade or so by now, and it’s been a reliable companion. JetBrains IDEs have a bit of a reputation for being slow, but their feature set is incredible: powerful refactoring tools, a great VCS UI (though I like magit even more!), a huge number of supported frameworks, integration with just about any testing library for any language, code coverage tools, powerful debuggers, etc.

Every so often I come across a paper, blog post, or (occasionally) video that completely changes how I think about a topic in programming languages and compilers. For some of these posts, I can’t even remember how I thought about the idea before reading it—it was that impactful.

When people say Rust is a “safe language”, they often mean memory safety.
And while memory safety is a great start, it’s far from all it takes to build robust applications.
Memory safety is important but not sufficient for overall r…

There's a concept that I've heard called by a lot of different names, but my favorite name for it is …

A fun, hands-on guide to writing your own compiler for a real-world programming language.

Code discussions contain relevant information. Isn’t it a shame that we
keep these in the centralized GitHub/GitLab servers, far away from our
decentralized Git code? As soon as we move provider, we’ll lose all old
discussions! And how do you ever find the pull requests back from 5
years ago? Symfony has implemented a lightweight solution to this problem
years ago using a less-known feature of Git: Git Notes.

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

Official website of the Pimalaya project.