The Emacsmirror is a growing collection of [Emacs] Lisp packages. All mirrored packages are available as [Git] repositories. In most cases this is done by mirroring the upstream Git repository, but if upstream uses something else, then the mirror nevertheless makes the package available as a Git repository.
One primary purpose of the Emacsmirror is to provide a comprehensive list of available Emacs packages, including packages which have gone out of fashion (but might later prove to be useful still).
Older efforts attempting to provide a comprehensive list of available packages, such as the [Emacs Lisp List][ell], over time collected an impressive list of dead links to packages which were no longer available anywhere.
With the Emacsmirror this won't happen. If a package's upstream disappears, then a copy remains available on the mirror. Once its upstream has disappeared a package is usually moved from the Emacsmirror to the [Emacsattic], where it is no longer updated. (The Emacsattic is a Github "organization" separate from the Emacsmirror organization, but it is considered part of the Emacsmirror project.)
If other mirrored packages still depend on a package whose upstream has disappeared or no longer maintains the package, then it is copied to the [Emacsorphanage]. The Emacsmirror then mirrors that repository from the orphanage. The orphanage repository serves as a temporary home until someone volunteers to take over as maintainer. While a package is in the orphanage, the maintainer of the Emacsmirror makes an effort to merge pull requests from users.
Note that in the past I have sometimes removed packages completely, instead of moving them to the attic, but going forward that should only happen in exceptional cases.
For more information about the Emacsmirror and the
which provides a user interface for browsing the package database,
visit the Emacsmirror homepage.
Adding new packages
Most packages that are available from Melpa are also available from the Emacsmirror. New packages are added to Melpa on a regular basis and after a short delay these packages are also semi-automatically added to the Emacsmirror. So there is no need to ask for new Melpa additions to be added to the Emacsmirror too. It will happen but it might take a few days.
To get a new package added to the mirror add it to Melpa instead. That way Melpa users benefit too.