Yeah, this seems half-thought-through. renv works at project level and isolates the dependencies of a project from your main library. groundhog.library() tramples over your library installing multiple versions. It also has the "cute" feature of auto-installing libraries if they aren't on your system already. Yuck. If you really wanted this script-only solution then you could go with the `versions` library, which already lets you specify an installation date.[1]

[1]: https://cran.r-project.org/web/packages/versions/index.html