Hi, I have long thought that --ad-hoc should be implied, as that is the mode I use 99% of the time, but I disagree that --pure should be the default. Most of the time I (and I suspect most other users) just want to temporarily augment the current environment with a package or two and I think that shouldn't require any special flags (neither --ad-hoc nor --pure). The current default behavior of making an environment from package dependencies is because that's how nix-shell worked (or at least how I thought it worked) and 'guix environment' was created as a clone of that tool. - Dave