NixOS/nixpkgs — pull request #1040 by coroa (2013-10-04 08:09:59+00:00)
Title: my-env: pull --norc shell flag out into shell parameter

as zsh's corresponding flag is called --no-rcs, the build environment
couldn't be configured to use zsh at all.

even then the custom PS1 won't work on zsh, but it's usable enough.