Hi, Christopher Baines skribis: > Yep, I've been experimenting with loading older revisions in to the Guix > Data Service, and this is one of the issues I came across. Nice! I’ve been thinking we should have time-traveling continuous integration. Like checking that we can build some Guix revision of the past in between two ‘core-updates’ merges. It would also be useful to flag known-bad revisions, but in a way the Data Service is already doing that for recent revisions. Thanks, Ludo’.