It is the systems programming language of the Java platform, if you see the JVM as an OS.<p>So you need to be comfortable with it, as there will always be cases you need to jump out of the alternative language into Java.<p>Also, most companies will only hire to work with Java on the JVM, because they don&#x27;t want to be hostage of the cool language some of the dev team guys&#x2F;contractors decided to use instead.<p>It is very rare to see traditional Java shops to use alternative languages.<p>Usually the ones using them are either startups or companies like Facebook and Twitter, which aren&#x27;t the typical business culture.