Currently fails with:

$ nix --extra-experimental-features 'nix-command flakes' eval .#legacyPackages
error: anonymous function at /nix/store/g5bl53zqkkc6pcr6izsbrhcs1fjkxdhd-source/pkgs/build-support/fetchurl/boot.nix:5:1 called with unexpected argument 'meta'

    at /nix/store/g5bl53zqkkc6pcr6izsbrhcs1fjkxdhd-source/pkgs/build-support/fetchzip/default.nix:22:2:

        21|
        22| (fetchurl (let
            |  ^
        23|   tmpFilename =
(use '--show-trace' to show detailed location information)

m1:

nix --extra-experimental-features 'nix-command flakes' build CACHIX_ACTIVATE_TOKEN=... cachix deploy activate ./result