I’m not sure how one would reach reflog the ability to read or write

is reflog very unfriendly UI? what would make it better?

It’s an algorithm question. If somebody gave me your solution in an interview I would ask them to solve the problem without a dependency. These questions are about demonstrating your ability to code whilst understanding space & time complexity.

Can you list ones you found valuable?

Postfix wasn’t in my university degree, nor do I think it should be. It’s useful to know about SMTP but it’s like saying you need to know the history of brick manufacturing to be a material engineer.

My perspective is that language is not as useful a metric as people believe it is. A lot of companies interview in languages that are not their own.

I don’t like Java myself mostly because the company’s that make heavy use of java tend to be slow moving giants that write classes like AbstractBeanFactoryFactory. I’m not a fan of the language much either. If had to pick a JVM language it would be Kotlin.

For salary’s maybe look at the StackOverflow survey. I’m not saying to dedicate your life to Zig but maybe Java is statistically not the optimal choice. Do be aware that this graph is the average, and I’m sure highly paid Java engineers are not an uncommon sight, it’s just that the masses of crappy enterprise jobs drag them down.