This is exceedingly rare... so you wrote a HashMap implementation in Java?? None of the custom maps discussed [here](http://java-performance.info/hashmap-overview-jdk-fastutil-g...) were enough? It must be a really rare problem you're working on if there's no library that provides an acceptable solution for it in Java.

> I would rather work with someone who knows how neural networks really work rather than who knows pytorch or keras

I would rather work with someone who knows general programming (which is not the same as algorithms - there's so much more to it!) and software design... but if working on a product that uses a framework heavily, good knowledge of that framework can be the difference between getting things done in minutes VS weeks (of painful and time-consuming battling with the framework to do thing the way you think they should be done, rather than how it's done within the framework).