I've been maintaining a fairly popular (~40k downloads/mo) react component library for about 4 years now. It is a clusterf'ck to keep things up to date with cha

I've been maintaining a fairly popular (~40k downloads/mo) react component library for about 4 years now. It is a clusterf'ck to keep things up to date with changes over time. React itself has broken things several times. I knew in advance that this would be a challenge, so when I started the project, I wrote a lot of unit tests. The first test for each component was just a snapshot output of it. Then I had other tests for functionality and have added tests over time for bugs. That has saved my ass so many times. I don't know how anyone maintains a JS project without comprehensive tests. Actually, I do... as you said, they never upgrade anything.