I've read your code and there is no reason to use all those libraries, it could have been done in a performant way with std libs. Why would you use fasthttp?
Did you read the post (there’s an attached blog post)? I was worried I wasnt giving golang a fair shake because the performance (under constraint) was so bad in comparison. Fasthttp did end up being faster also, I just had to fall into a bit of a pitfall first.