I’ve been learning a lot about low-level programming languages lately, and for a long time there has been one thing that has interested me: SIMD (or ‘single instruction, multiple data’) code. I’ve seen a lot of articles about having massive performance gains by utilizing SIMD and wanted to learn how to do it myself. This article is a journey into implementing ~60% faster substring searching compared to Zig’s std.mem.indexOf using a SIMD-friendly algorithm.