Since commit fa2bb2d33f, the nix-build
subprocess is called without capture_output=True. Therefore, proc.stderr
is None. The subprocess stderr is already being dumped to stderr, so
there is no need for doing a print.
See Changelog.md for changes.
* adapt data interface for new sdist dependency graph format
* change wording in readme
* wheel support + concept providers
* overlay support WIP
* overlay support
* extras support for nixpkgs
* machnix as overrides
* granular provider settings + custom autoPatchelfHook
* improve overlay generator, remove prefer_new
* unify nixpkgs src
* update interface, bump version and examples
* fixes and updated docs
