I think all Scala katas are slow (in a compiling sense). For example, I tried this simple kata on Scala and got ~5-6 seconds time. Running time was 65ms, so the remaining time is the compiling time.

From my own experience, this is typical behavior for all Scala projects that use SBT as a build tool.

Thanks)
These 7 seconds consist of compiling time + running time.
Most of the time is the compiling time.

• The running time for the Sample Test Cases is less than the second.
• The running time for the full Test Cases (with random tests) is ~2 seconds.

Reducing random tests will not give us serious benefits. Compiling time will remain the same.

This is my first translation, so maybe I'm wrong.

Scala translation has been added.