[nicoburns]

> Tens of clean builds? I'm very curious: why?

It's partly a privilege of being able to. I have an MacBook M1 Pro machine with 10 cores, so clean release builds are tolerable. The slowest project to compile I work on regularly in Servo and I can do a clean release build of that in 3-4 minutes. Most of the other projects I work on it's more 30s to 2m max.

It's also a disk space thing. Between working on multiple different projects (I have 200 projects in total in my "open source repos" directory, most of those I only interact with very occasionally, but 5-10 in a day wouldn't be particuarly unusual for me) and switching between branches within projects I can build up 10s of GBs of data in the target dir within a few hours. And I don't have the largest SSD, so that can be a problem! So it's become habit to cargo clean reasonably regularly.

Finally, sometimes I am explicitly testing compile time performance (which requires a clean build each time) or binary size (which involves using additional cargo profiles, exacerbating the disk space issues).