The implementation used in this article is actually in C (which is the official, extremely well-tested one), with bindings to the Go language through something

The implementation used in this article is actually in C (which is the official, extremely well-tested one), with bindings to the Go language through something called CGo. There's no "server", it's all just code run in your application directly, so think of it more as a library that can access a special database file on your disk. I don't know how it's done in PHP, I would think it's similar.