I've been using Scala for years now, and have never really found compile times to be an issue. I spend most of my time writing the code and thinking about it. C

I've been using Scala for years now, and have never really found compile times to be an issue. I spend most of my time writing the code and thinking about it. Compiling a few times an hour takes a few seconds each time. Most Scala tools these days use incremental compilation. My IDE (IntelliJ) underlines errors using a background thread, so by the time I hit compile I already know where the issues are. It doesn't feel very different to compiling Java code (which Kotlin is aiming to match the compile times of). If you want to optimize for only the compile dimension then Go and Pascal have very fast compilers. Python removes the need for compiling completely if that's really important to you (much faster than waiting for javac).