I never got panda to install, so I use zef. The only module I've installed was Readline, to shut up the blind nagging whenever I run perl6 for a repl.
Zef seems to have left files containing the string Readline in share/perl6/site, plus .perl6/precomp. The filenames are hashes, perhaps from a git clone that zef used to pull Readline? Like I said, it's early days.
