The time crate used to be fairly simplistic and thus mostly unusable for our purposes. So chrono was built on top of it. The time crate since then however got a new maintainer and it's more lightweight than chrono and fits what we use chrono for pretty well. chrono seems to be pretty unmaintained for a while now and there also seems to be a vulnerability in it (race condition in the underlying libc's setenv). So yeah it probably makes sense to look into this.