It looks simple from the outside. It's not the hot mess ftp is with having to manage multiple connections to do anything.

I think HTTP before HTTP/2 _is_ simple, but it limits its usefulness too, leading to pain when you want to do anything outside of what was included in the initial design.

But, I'd even argue the best version of HTTP is HTTP/1.0 + ability to specify Host: header (many web servers accept it when requesting via HTTP/1.0 even though it's been introduced in 1.1). The later extensions, including HTTP/1.1 are much harder to implement, thus limiting your implementation options and what you can do with it.

In terms of usefulness for the web (browsers) on the other hand HTTP/3 is the best, but it's far from simple and I doubt anyone would call it that too. Version 1.0 was really simple though, and that makes it beautiful

Parsers for HTTP/1.x are kind of a solved problem though, even in unsafe languages.

The danger is always when someone thinks they can do it themselves as a 30 minute side quest.

The only other protocols I'm relatively familiar with are email and nntp protocols, mostly smtp and pop3. HTTP as a protocol is pretty similar at it's basic constructs. Compared to HTTP/2 or newer, it's insanely simple... IMAP and FTP, those are much more convoluted and difficult to get right even on a practical level.

HTTP is also pretty universal at this point with simple client and server libraries for pretty much every language or platform under the sun that could use them. You don't have to roll your own, unless you're rolling your own language, and even then, you can probably burrow an existing C implementation/library.

It’s one thing to be hard in practice like IMAP where you get basically need to test again real world servers to see what they do and then build against that.

But tfa makes a good point about http having some odd complexities even on paper that we kinda take for granted.

I feel like I just wrote an LLM-level comment but I definitely clicked the article thinking it was just going to be about the first case.