Ask HN: Side gigs, contracting, guidance for back end developer?

I'm looking to improve my financial situation, and I wondered, where do you guys go to pick up some short term backend remote contracts when you happen to be in situation like this?

I'm a scala developer, and I can't find any positions like that, which I understand... what other skill should a profficient Scala developer/backend dev pick so that he can get these short term gigs? Obviously javascript is very popular, but it's very limited skill transfer between scala<->javascript, and frontend world moves very quickly... what are your goto-technologies when you need some extra cash? JavaEE? Php?

I know the obvious answer - learn frontend, pickup frontend work. But I'm looking for solution that maximises transfer of skills inbetween, so I'm not completely out...

Any suggestions or guides would be very much appreciated.

p.s: my experience: scala(a lot) | php ages ago | C# very well | little to none javaEE experience | little to none html5/javascript experience