Although several hundred Emacs Lisp libraries exist GNU Emacs does not have an (internal) package manager.

I guess that most users would agree that it is currently rather inconvenient to find, install and especially keep up-to-date Emacs Lisp libraries.

These pages make life a bit easier

• Emacs Lisp List - Problem: I see dead people (links).
• Emacswiki - Problem: May contain traces of nuts (malicious code).

These are some package managers

• XEmacs package manager
• package.el - ELPA
• pases
• install.el
• install-elisp.el
• plugin.el
• use-package.el
• jem-pkg.el
• epkg/elm - the one I am working.

And this are some packages that provide functionality that might be useful in a package manager

• ell.el - Browse the Emacs Lisp List
• genauto.el - helps generate autoloads for your elisp packages
• date-calc.el - date calculation and parsing routines
• strptime.el - partial implementation of POSIX date and time parsing
• wikirel.el - Visit relevant pages on the Emacs Wiki
• loadhist.el, lib-requires.el, elisp-depend.el - Commands to list Emacs Lisp library dependencies.
• project-root.el - Define a project root and take actions based upon it

So I would like to know from you what you consider important/unimportant/supplementary... in a package manager for Emacs.

Some ideas

1. Many packages (incorporate the Emacs Lisp List and other lists of libraries).
2. Only packages that have been tested.
3. Support for more than one package archive (so people can choose between many/tested packages).
4. Dependency calculated based on required features only.
5. Dependencies take particular versions into account.
6. Only use versions that have been released upstream.
7. Use versions from version control systems if available.
8. Packages are categorized.
9. Packages can be uninstalled and updated not only installed.
10. Support creating fork of upstream version of packages.
11. Support publishing these forks.
12. Support choosing a fork.
13. After installation packages are activated.
14. Generate autoloads.
15. Integration with Emacswiki (see wikirel.el).
16. Users can tag, comment ... packages and share that information.
17. Only FSF-assigned/GPL/FOSS software or don't care about license.
18. Package manager should be integrated in Emacs.
19. Support contacting author.
20. Lots of metadata.
21. Suggest alternatives before installing a particular package.

Some discussions about the subject at hand

• emacs-devel 20080801
• comp.emacs 20021121
• RationalElispPackaging

I am hoping for these kinds of answers

• Pointers to more implementations, discussions etc.
• Lengthy descriptions of a set of features that make up your ideal package manager.
• Descriptions of one particular disired/undisired feature. This has the advantage that the regular voting mechanism allows us to see what features are most welcomed. Feel free to elaborate on my ideas from above.
• Surprise me.