A use case for Foreign Function Interface (FFI) in PHP

I came across the Blazingly Fast Markdown Parsing in PHP using FFI and Rust by Ryan Chandler, which is a good read if you just heard about FFI. Available since PHP 7.4, by the way.

FFI stands for "Foreign Function Interface". [...] it allows you to interact with functions written in a totally different programming language.

The article is easy to follow and very pragmatic. No Rust experience is needed.