Library I regretted adding within a week

I added a dependency last month because it solved a problem in twenty minutes. Saved me a day, at least.

A week later I needed to change one small behavior in that dependency. Not a big change. A small one. And the library was not built for it. So I forked it, and now I maintain a fork, and the fork is slowly drifting away from the original.

The twenty minutes I saved have turned into an ongoing cost I did not price in.

I am not against dependencies. I am against the part of my brain that treats them as free. Nothing you add to a project is free, it is just deferred, and the bill arrives at the worst possible time.

What is a dependency you wish you had written yourself? And did you ever go back and replace one?