Serving 200M requests per day with a CGI-bin

I got my start in the CGI era, and it baked into me an extremely strong bias against running short-lived subprocesses for things.

We invented PHP and FastCGI mainly to get away from the performance hit of starting a new process just to handle a web request!

It was only a few years ago that I realized that modern hardware means that it really isn't prohibitively expensive to do that any more - this benchmark gets to 2,000/requests a second, and if you can even get to a few hundred requests a second it's easy enough to scale across multiple instances these days.

I have seen AWS Lambda described as the CGI model reborn and that's a pretty fair analogy.

I think you might have found that CGI scripts deployed as statically-linked C binaries, with some attention given to size, you might've not been so disappointed.

The "performance hit of starting a new process" is bigger if the process is a dynamically-linked php interpreter with gobs of shared libraries to load, and some source file, reading parsing compiling whatever, and not just by a little bit, always has been, so what the author is doing using go, I think, would still have been competitive 25 years ago if go had been around 25 years ago.

Opening an SQLite database is probably (surprisingly?) competitive to passing a few sockets through a context switch, across all server(ish) CPUS of this era and that, but both are much faster than opening a socket and authenticating to a remote mysql process, and programs that are not guestbook.cgi often have many more resource acquisitions which is why I think FastCGI is still pretty good for new applications today.

That's likely true - but C is a scary language to write web-facing applications in because it's so easy to have things like buffer overflows or memory leaks.

CGI basically is a protocol between the webserver and some process. It didn't go out of fashion because of C (many/most CGI scripting for a time was perl and php or even bash), it went out of fashion because people wanted (or were told that smart people did this) to use languages that had runtimes which were expensive to run in a fork()+exec() execution model like Java.

You can use it with any language that can read stdin and write stdout. Yes, printing and reading.