Holly effin durians! I just migrated from 0.18.0 on a 51K app where changing this one critical module caused ~3min compile time. And now with 0.19.0:
Success! Compiled 197 modules.
real 0m5.324s
user 0m4.845s
sys 0m0.436s
But then there is 0.19.1:
Success! Compiled 1 module.
real 0m0.158s
user 0m0.060s
sys 0m0.082s
Are. You. Kidding. Me.
What have you done, Evan!