I recently built and released an in-memory B+Tree library for the JVM, mainly because I wanted to explore the cache-locality and GC overhead issues of pointer-heavy Red-Black Trees.When it finally compiled and started wining over TreeMap in JMH benchmarks, I thought I was basically done.

Turns out, not even close.

Over the last few weeks I went down a rabbit hole of:

- Jqwik property-based testing with 214,000+ randomized structural cases. - Serialization compatibility and serialVersionUID. - JFR and -Xlog:gc to figure out whether some benchmark results were actually anomalies. - Strictly following JDK SortedMap contracts instead of taking optimization shortcuts. - added Jacoco coverage(95.9%) and Codecov(91%) - Trying every possible way and optimization if needed - looped massive time Otimization->Correctness->Bencmark->reoptimization and the loop goes until it reaches maximum state. The final result was a 30~46% memory saving and 2x (sometimes up to one API 10x) speedup. Maven Central shows 1.7K, 154 unique sources and 47 downloads, though I suspect a lot of that is just CI/CD caching.

And it made me ask:

For people who actually evaluate open-source dependencies at companies, what is your checklist? At what point do you look at a solo developer's GitHub repo and think, "Yeah, I'd be comfortable putting this in production"?