nix_file is legacy and we go for specific project_paths for each separate Nix R environment to enforce isolated projects. that means that shell.nix will have percedence over default.nix, which is how nix-shell <project_dir> behaves (we call that process through {sys}.
removes an apparent bug reported here: #178
nix_fileis legacy and we go for specificproject_paths for each separate Nix R environment to enforce isolated projects. that means thatshell.nixwill have percedence overdefault.nix, which is hownix-shell <project_dir>behaves (we call that process through {sys}.