@User:  We have a script in the repo that generates the skywater-pdk from sources that will zero the datestamp in GDS files;  that's for the same reason:  That it is effectively impossible to write the same GDS twice because the timestamp will get updated.  Then, the git scripts will see a modified binary and do a wholesale replacement of something that should not have changed.  That was particularly troublesome in skywater-pdk because the repository is already so large.  But caravel effectively has the same issue.  So I will see about copying that timestamp modification script to open_pdks and see if we can use it within the openlane and/or caravel scripts to keep the repository sizes from going ballistic.