<appendix xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink"> <title>Bugs / To-Do</title> <itemizedlist> <listitem><para>The man-pages generated from the DocBook documentation are ugly.</para></listitem> <listitem><para>Generations properly form a tree. E.g., if after switching to generation 39, we perform an installation action, a generation 43 is created which is a descendant of 39, not 42. So a rollback from 43 ought to go back to 39. This is not currently implemented; generations form a linear sequence.</para></listitem> <listitem><para>For security, <command>nix-push</command> manifests should be digitally signed, and <command>nix-pull</command> should verify the signatures. The actual NAR archives in the cache do not need to be signed, since the manifest contains cryptographic hashes of these files (and <filename>fetchurl.nix</filename> checks them).</para></listitem> <listitem><para>It would be useful to have an option in <command>nix-env --delete-generations</command> to remove non-current generations older than a certain age.</para></listitem> <listitem><para>There should be a flexible way to change the user environment builder. Currently, you have to replace <filename><replaceable>prefix</replaceable>/share/nix/corepkgs/buildenv/builder.pl</filename>, which is hard-coded into <command>nix-env</command>. Also, the default builder should be more powerful. For instance, there should be some way to specify priorities to resolve collisions.</para></listitem> </itemizedlist> </appendix>