I built it because when people search Google for common PDF tasks, many of the tools they find upload documents to a server. I wanted an option that keeps files local instead.

I posted an earlier version on HN last spring: https://news.ycombinator.com/item?id=43880962

At the time it only supported a small set of features. Over the last 10 months I rebuilt large parts of it and expanded it to nearly 40 tools, including several ideas that came from comments in that earlier thread.

There is also now a desktop app for macOS, Windows, and Linux, plus a CLI/SDK for developers.