nix3-store
Manipulate the Nix store.
TLDR
Collect garbage, i.e. remove unused paths to reduce space usage
$ nix store gc
Hard-link identical files together to reduce space usage
$ nix store optimise
Delete a specific store path (most be unused)
$ nix store delete [/nix/store/...]
List a contents of the store path, on a remote store
$ nix store --store [https://cache.nixos.org] ls [/nix/store/...]
Show the differences in versions between two store paths, with their respective dependencies
$ nix store diff-closures [/nix/store/...] [/nix/store/...]