We Built Lightpanda in Zig

Summary

Why We Built Lightpanda in ZigBecause We're Not Smart Enough for C++ or RustFrancis BouvierCofounder & CEOTL;DR To be honest, when I began working on Lightpanda, I chose Zig because I’m not smart enough to build a big project in C++ or Rust. I like simple languages. I like Zig for the same reasons I like Go, C, and the KISS principle. Not just because I believe in this philosophy, but because I’m not capable of handling complicated abstractions at scale. Before Lightpanda, I was doing a lot of Go. But building a web browser from scratch requires a low-level systems programming language to ensure great performance, so Go wasn’t an option. And for a project like this, I wanted more safety and modern tooling than C. Why We Built Lightpanda in Zig Our requirements were performance, simplicity, and modern tooling. Zig seemed like the perfect balance: simpler than C++ and Rust, top-tier performance, and better tooling and safety than C. As we built the first iterations of the browser and dug deeper into the language, we came to appreciate features where Zig particularly shines: comptime metaprogramming, explicit memory allocators, and best-in-class C interoperability. Not to mention the ongoing work on compilation times. Of course it’s a big bet. Zig is a relatively new language with a small ecosystem. It’s pre-1.0 with regular breaking changes. But we’re very bullish on this language, and we’re not the only ones: , , , and are all building with Zig. And with , big tech is taking notice. Here’s what we’ve learned. What Lightpanda Needs from a Language Before diving into specifics, let’s talk about what building a browser for web automation requires. First, we needed a JavaScript engine. Without one, a browser only sees static HTML: no client-side rendering and no dynamic content. We chose V8, Chrome’s JavaScript engine, because it’s state of the art, widely used (, ), and relatively easy to embed. V8 is written in C++, and doesn’t have a C API, which means any language in...