I don't see any real justification here for why it was worth the effort to port the code from Kotlin/Java to Scala other than reusing their "well-established sk

I don't see any real justification here for why it was worth the effort to port the code from Kotlin/Java to Scala other than reusing their "well-established skills with Scala" and "using sbt for our Android app has also allowed us to leverage our unified build system". They're both valid reasons, but they're not so much technical decisions as pragmatic ones for that particular company. The post states "hopefully I will be able to illustrate how Scala can dramatically improve your experience while developing Android applications". This claim isn't addressed in the post at all however. For example, it states "Scala has a pretty decent concurrency primitive in Future" and explains how to use them, but doesn't say what they offer over and above Java futures or Kotlin coroutines. Most of the post is talking about how they migrated their codebase and any compatibility or technical hurdles that were overcame on the way (e.g. the sbt/Gradle mismatch), not about why Scala was a better choice technically or what benefits it offers over Java or Kotlin. There's no mention either of other practical issues such as the large standard library, method counts, compile times and so on. The addition of a few strong comparisons would be welcomed. As it stands, the post feels more like "please don't fire me" than "where's my promotion?".