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.

A Jujutsu tutorial that requires no previous experience with Git or other version control systems.

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.

This web app displays notes and slides in separate windows,
keeping both synchronised.
It accepts simple, double-width, or double-height PDF presentations:

I feel uneasy about design patterns.
On the one hand, my university class on design patterns revived my interest in programming.
On the other hand, I find most patterns in the Gang of Four book to be irrelevant to my daily work;
they solve problems that a choice of programming language or paradigm creates.

My litmus test of a good design pattern is its cross-disciplinary applicability.
I’m more likely to accept an idea that pops up in fields beyond software engineering.
And the most convincing patterns are the ones that help me in everyday life.

This article describes a universal pattern that billions of people rely on daily, but software engineers rarely discuss—the plan-execute pattern.

The solution to all of these problems

I humbly put forward that modern web development provides us all the utilities to move away from class names and implement something much more robust, with some fairly straightforward changes:

Attributes

Attributes allow us to parameterise a component using a key-value representation, very similar to Map<string, T>. Browsers come with a wealth of selector functions to parse the values of an attribute.

My take on what could be a project template for Django advanced usage, with modern tooling (for Python and UI dependencies, as well as configuration/environment management), but not too opinionated.

Security testing starts with understanding vulnerabilities. The CVE website lists known software flaws. The OWASP Top Ten highlights common weaknesses. With this knowledge, we can improve our Go development. This article shows how to put in place robust practices. They are to: fuzz inputs, verify dependencies, and use static analysis tools (SAST).

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

Most functional languages rely on some garbage collection for automatic memory management. They usually eschew reference counting in favor of a tracing garbage collector, which has less bookkeeping overhead at runtime. On the other hand, having an exact reference count of each value can enable optimizations, such as destructive updates. We explore these optimization opportunities in the context of an eager, purely functional programming language. We propose a new mechanism for efficiently reclaiming memory used by nonshared values, reducing stress on the global memory allocator. We describe an approach for minimizing the number of reference counts updates using borrowed references and a heuristic for automatically inferring borrow annotations. We implemented all these techniques in a new compiler for an eager and purely functional programming language with support for multi-threading. Our preliminary experimental results demonstrate our approach is competitive and often outperforms state-of-the-art compilers.

In this post, I talk about pleasant but seemingly minor features in personal sites

Most programming language ecosystems provide assert functions in their testing libraries but not Go's. Go's standard testing package follows a more direct and to-the-point approach.