Yes, a hope of mine is that we can stop using "hash derivation modulo" entirely.

I've recently started some fancy formal spec-level documentation here https://github.com/NixOS/nix/pull/14408 The "resolution" equivalence class is both simpler and better than the "hash derivation modulo ..." one.

(The fact that it is a mouthful to say what the derivations are modulo kinda gives the game away! I put "hash quotient derivation" in the docs to side-step the issue.)