local flake registry freezes branches

[bbjubjub2494]

Expected Behavior

Running flk update on a devos machine should update the nixos and override inputs to the tip of the appropriate git branches.

Current Behavior

flk update idempotently converts both inputs to the equivalent path:/nix/store/xxx-source.

Possible Solution

The two nix.registry entries generated by hosts/default.nix seem to be the problem: they effectively force any occurrence of nixpkgs or nixpkgs/release-20.09 to resolve to the specific store path at hand.

Steps to Reproduce

1. get a on a devos machine
2. try to update any flake that pulls in nixpkgs and/or nixpkgs/release-20.09
3. observe commit message and contents of flake.lock

Context

Your Environment

I'm on 0.7 but I think it's still in master. Here's the commit where it happened.