Compiler performance


Hello all,

how do you feel about the performance of the Kotlin (M5.1) compiler?

I am evaluating Kotlin M5.1 in a small project (currently about 15-20 classes). Hitting Build => Rebuild Project takes 11-14 seconds on a decent developer MacBook Pro Retina (2,6 GHz i7 CPU, 16GB RAM, SSD, JDK 7 current IntelliJ 12).
Is there something I can do to improve the compiler performance?
Or may I expect noticeable improvements in the future?

The Kotlin FAQ ( claims

The main design goals behind this project are [...] that compiles at least as fast as Java, [...]

At least for now, this goal has not been met. Or is it just my setup?

Thanks for any input,


We are not at all satisfied with the performance of present compiler. It is not your setup, but neither is it the design of the language. Quite a few improtant optimizations are yet to be implemented. Hopefully, we can complete them soon.


I was about to ask a question similar to @nanosk’s and then I found this thread. Is the same thing true today with the 1.1-M04 kotlin?

In one case I’ve got 48 files and about 6000 lines (not sure what percent comments) compiling in about 12 seconds. (gradle compileKotlin). Computer is a late 2011 Macbook Pro with 10GB RAM.