"I shipped 129 tools with no backend. Here is what broke."
There is no backend. The site is a static export on a CDN and every tool runs in the browser — pdf-lib and pdf.js for documents, Canvas and the File API for images, Web Workers for anything slow. It works with the network disconnected, which is the simplest way to check the claim. toolsholic.com
We haven't written up this one. Dev.to has the full story — the link below goes straight to it.