If you need to use an older version of a package and don’t have a packrat/renv lockfile already, then packrat/renv are not going to help you. mran/checkpoint co

If you need to use an older version of a package and don’t have a packrat/renv lockfile already, then packrat/renv are not going to help you. mran/checkpoint could though. I agree packrat (which I created) was a poor solution for most users. renv is far better and more usable.