This was not my experience. Of course you need a team that has the drive to learn the language, whatever it is.
If you go out on your own and decide to build your project with Scala and a big focus on using a functional style but no one else is following, you are going to have a bad time.
I'd like to know what are your issues with Scala and versions because we don't have these. IMHO, Scala is years ahead of Java and it's possibly so different that comparing them does not even make sense.
The transition from Java to Scala is awkward because you can do most of the things you do with Java in Scala. With that said, I think it's counter productive to do it. Scala is very different and approaching it with an imperative Java (even an OO) style is the worst thing to do.
One thing that I realized is that some people can go off and write cryptic code in Scala, very easily. This is true of other languages as well but in Scala, you can do a lot of things that will make you regret it the next time you try to read the code.
The last problem we had was with various Fintatra / Finagle libraries written in 2.10.
We wanted to upgrade some other - not all - projects to newer versions of 2.11.
It wouldn't work because our Thrift clients were incompatible with stubs compiled with 2.10. We didn't have the time and manpower to rewrite all the dependent services, and so we're stuck on 2.10.
This is something that'd never happen with even old-school SOAP or similar web services. It kind of left a bad taste in my mouth.
If you go out on your own and decide to build your project with Scala and a big focus on using a functional style but no one else is following, you are going to have a bad time.
I'd like to know what are your issues with Scala and versions because we don't have these. IMHO, Scala is years ahead of Java and it's possibly so different that comparing them does not even make sense.
The transition from Java to Scala is awkward because you can do most of the things you do with Java in Scala. With that said, I think it's counter productive to do it. Scala is very different and approaching it with an imperative Java (even an OO) style is the worst thing to do.
One thing that I realized is that some people can go off and write cryptic code in Scala, very easily. This is true of other languages as well but in Scala, you can do a lot of things that will make you regret it the next time you try to read the code.