Although I agree they have a good attitude towards deprecation and backwards compatibility, I do not believe their progressive attitude works necessarily implies a lax attitute to backwards compatibility.
Investigation is underway for more sweeping changes where backwards compatibility can be broken on the fundamental level. This is the Dotty project [1], which will influence development of Scala 3.
Umm, Scala 3 = Scala "Don Giovani" = Scala 2.14 (backed by Dotty); that's the gist I got from the linked post (thus the DOT calculus reference in this section of the document)
A ways away, but they're spelling it out now: der Dotty cometh ;-)
Sounds like 2018 if the roadmap plays out as planned. Looks tasty, wish it were more like 2016.
Investigation is underway for more sweeping changes where backwards compatibility can be broken on the fundamental level. This is the Dotty project [1], which will influence development of Scala 3.
[1]: https://github.com/lampepfl/dotty