Overall looks good, but it's a shame that flat mode is opt-in instead of the default - this is the sane way of doing package management. Would have been nice to

Overall looks good, but it's a shame that flat mode is opt-in instead of the default - this is the sane way of doing package management. Would have been nice to flip the options over so you have to explicitly allow multiple versions of the same package - which you could automatically enable if you're converting from npm.