@pmusaraj recently improved our build yesterday to skip unused locale compression, here’s what I get with
time ./launcher rebuild app
now on the very same machine:
| real | user | sys | |
|---|---|---|---|
| 2019 scooter | 2:40 | 0.2s | 0.1s |
Amazing! 
that is a 25% improvement!
(I rebuilt twice, because the timing of the first run is affected by the image download time which isn’t technically rebuild time.)