How does it actually work?

When you run:

curl -sL https://yabs.sh | bash

this command uses curl to download a shell script from the URL https://yabs.sh and immediately executes it with bash.

However, when we open https://yabs.sh in a browser, we are redirected to the home page of the YABS project on GitHub. So, what is actually being downloaded in this case?

We can look at the HTTP response instead of running the script. The easiest way is to send a HEAD request, which only shows the headers:

curl -I https://yabs.sh
HTTP/2 301
date: Fri, 10 Oct 2025 06:08:47 GMT
location: https://raw.githubusercontent.com/masonr/yet-another-bench-script/master/yabs.sh
...

This tells us that https://yabs.sh doesn't host the script itself. It simply redirects to the actual file hosted on GitHub at:

https://raw.githubusercontent.com/masonr/yet-another-bench-script/master/yabs.sh

So, when you run the original command, that is the script being downloaded and executed.