Swap, ZRAM, Zswap and Hibernate on NixOS

I agree with everything else here, but swap files on btrfs should probably be avoided whenever possible [0].

[0]: https://btrfs.readthedocs.io/en/latest/Swapfile.html

Thanks for this. So weird though - I literally spent the better part of the weekend reading and learning all about the differences between zram and zswap and ultimately deciding to switch out my previous zram config for zswap on my NixOS system! So seeing this pop up on my hackernews feed felt a bit spooky…