Defense in depth:

1) Write tests for the new functionality

Don’t trust that

2) Adopt the new functionality in existing API so the tests for that also get coverage

Still don’t trust that

3) Grab another team’s project, replace all their versions of similar stuff with mine even where it doesn’t make sense to, make sure their tests also still pass

STILL don’t trust that

4) Install it on my work laptop and use it for a while

I still don’t trust it but I’ve run out of test ideas so, merged 🤞