I was just going to say that. I'm guessing what was meant was maybe the redirection logic is all happening in the client, which is true. However, when you just read the title I assumed it meant everything, even the storage of the address itself, was being stored in the client. That didn't make sense to me, because you need to be able to share the links. Then I saw it was using jsonstore.io under the covers and the world made sense again.

goal of my project was to build a url shortner which can be hosted even in GitHub/Gitlab without any need to buy a costly PHP or NodeJs or Other hosting.