The billstclair/elm-recovered package is for recovering packages that have been removed from GitHub. The basic idea is that you restore the source for the package to your own GitHub repository, but prepend Recovered. to all the module names, to keep the recovered package from colliding with multiple inlined copies of the lost code.
This package has only this README file, plus a Recovered module.
To add a newly recovered package, modify its source to add the Recovered. prefix to all of its module names, elm package publish it, then submit a pull request to https://github.com/billstclair/elm-recovered, adding the new package to the list below in this README.md file (alphabetical by the package name after the user prefix). I'll take care of bumping the version number and changing Recovery.elm to match.
Bill St. Clair 27 June, 2018