[adriaanm]

The only thing on your list on your blog [1] that's still true is that we care about PL research. Since 2.10, we've worked really hard on improving the migration between major versions, and the feedback has been very positive. We'll keep working on finding the right balance between ease of migration and fixing issues in the libraries. Scala 2.13 will be a library release, with further modularisation of the library (towards a core that we can evolve much more slowly, and modules that can move more quickly, but where you can opt to stay with older versions as you prefer).

We've also invested heavily in incremental compilation in sbt. Sbt is meant for use as a shell, and it's super powerful when used like that. When I'm hacking the compiler in IntelliJ, recompiles of some of the biggest source files in the compiler (Typers.scala, say) take just a few seconds. I rarely have time for office chair sword fights anymore.

With Scala 2.13, half of my team at Lightbend is dedicated to compiler performance. We'll have some graphs to show you soon, but our internal benchmarking shows our performance has steadily improved since 2.10.

[_Codemonkeyism]

I still have the problem of upgrading because not all of the libraries are cross compile or do work. At the end of last year we've upgraded one library which cost us many days.

Next is upgrading Lift to 3.0 which will be a nightmare (again).

"We've also invested heavily in incremental compilation in sbt."

Yes, I read this over and over again, and I see micro benchmarks posted.

Using SBT with continuous unit testing I can't feel a difference - or it is so slow with a major code base that it's still much to slow and I judge it having no progress. Either way, after years it is still too slow (newest Scala + newest SBT).

"I rarely have time for office chair sword fights anymore."

Today I expect Kotlins practically instant compilation. 10 seconds for compiling some changed files is already to much for rapid development with TDD/Web, it breaks my flow, but YMMV.

"We'll have some graphs to show you soon,"

See above, I've seen dozens of micro benchmarks that claim improvements, in the end it doesn't show up in my real projects - at least in mine and the person who migrated to Go in the linked article. And all the other blog post authors that moved away from Scala towards something faster (Kotlin, Java 8, Go, ...)

But as I've said, I've moved on to Kotlin for new projects because for me Scala is a lost course.

[_Codemonkeyism]

Another site note: I would never argue with my users and tell them how wrong they are about the product and that their perception of the lack of some feature or quality is wrong.