What is a Matrix? A Miserable Pile of Coefficients!

JSON is extremely popular but deeply flawed. This article discusses the details of JSON’s design, how it’s used (and misused), and how seemingly helpful “human readability” features cause headaches instead. Crucially, you rarely find JSON-based tools (except dedicated tools like jq) that can safely handle arbitrary JSON documents without a...

I will often say that the so-called “C ABI” is a very bad one, and a relatively unimaginative one when it comes to passing complicated types effectively. A lot of people ask me “ok, what would you use instead”, and I just point them to the Go register ABI, but it seems most people have trouble filling in the gaps of what I mean. This article...

Another explainer on a fun, esoteric topic: optimizing code with SIMD (single instruction multiple data, also sometimes called vectorization). Designing a good, fast, portable SIMD algorithm is not a simple matter and requires thinking a little bit like a circuit designer. Here’s the mandatory performance benchmark graph to catch your eye. ...

I write compilers for fun. I can’t help it. Consequently, I also write a lot of parsers. In systems programming, it’s usually a good idea to try to share memory rather than reuse it, so as such my AST types tend to look like this. pub enum Expr'src> { Int(u32) Ident(&'src str), // ... }Rust Whenever we parse an identifier, rather than copy its...

The other day, I saw this tweet. In it, Andrew Gallant argues that reaching for LLVM IR, instead of assembly, is a useful tool for someone working on performance. Unfortunately, learning material on LLVM is usually aimed at compiler engineers, not generalist working programmers. Now, I’m a compiler engineer, so my answer is of course you should...