[scientism]

That's a very roundabout way to solve an actual problem. In many cases you don't pin your package version to _latest_ (whatever that date is) and you need a more fine-grained solution to keeping package versions. I don't think that solves this and I don't know if you can do it with checkpoint.

[ggrothendieck]

Of course it is possible to screw up but if you don't update your packages and record the date that does not seem to be R's fault.