[Nix-dev] hack the source, then install

[Sergey Mironov]

Hi. Is it possible to continue installation after hacking the sources via

      nix-build $MY_NIX_ROOT/nixpkgs --run-env -A "$attr"
?

The idea is to be able to quickly hack the source and see if it works
or not. If it is, one probably may generate diff against the original.
What if this  'inplace development' is the feature everybody want to
have?

Sergey.