NixOS -- what I use -- gets mentioned here pretty frequently, so I don't just want to do an ad. But: walled garden? there's no wall. Multiple versions? Triviall

NixOS -- what I use -- gets mentioned here pretty frequently, so I don't just want to do an ad. But: walled garden? there's no wall. Multiple versions? Trivially. Copying applications between machines? `nix-copy-closure` is a joy to use, no exaggeration. And interdependency hell? Nix takes some pretty heroic measures to make builds reproducible, which work surprisingly well. The proliferation of formats is pretty irrefutable; you're meant to put your source code out there and let the distro maintainers worry about it. That's no help of course if you want to ship closed-source binaries, but Linux emphasizing open source goes a little deeper than package managers. Anyhow, maybe these are counterarguments and maybe it's just "some people who agree with you wrote a package manager." The main thing is the downsides can be fixed, and have been.