The removed package crux is unrelated to debian-med https://tracker.debian.org/pkg/crux
At least crux is to be found https://blends.debian.org/med/thermometer/ https://salsa.debian.org/med-team/crux The packagelist only lists crux-toolkit (not on the thermometer page) https://blends.debian.org/med/tasks/packagelist Medical category I,ll try to keep up. https://www.gezapig.nl/Software/Category/Medical2021.html
