[Measter]

Typically in an edit/compile cycle you'd only compile your dependencies once for each build type (check, debug, release). Unless you change a dependency's feature flag, the compiler will just re-use what's already been compiled.

If you clean your build folder, things will need to be rebuilt from scratch. Likewise if you change your compiler version.

[alkonaut]

It seems a CI system should be able to work the same way and cache the dependencies just like a local build.

If it does, then the long compile times are almost never encountered for neither developers nor CI. So are they really problematic?