Five years ago, Scala seemed like the next big thing in programming languages because it elegantly enabled functional programming within an object-oriented paradigm. Today, Scala’s popularity seems to be fading, with companies like LinkedIn and Yammer moving away from it. The TIOBE index (www.tiobe.com) of software language popularity ranked Scala at #13 in 2012; now it’s fallen to #32 in August 2016, being used by less than .6% of the programming community.
Here’s another ominous sign for Scala: Lightbend, its parent company, is now releasing new frameworks with a Java API before the Scala version. Anecdotally, as CTO of a leading software product engineering company, I meet many software development managers, and I know of at least two who have made the painful decision to abandon Scala after more than a year of adoption. What happened? What gave Scala its initial popularity boost, and what caused its decline? Are there any use cases for which Scala is still the best choice?