some of my systems need to have an option for cloning + building with git submodules enabled, looks like this is the required option for git-go is

RecurseSubmodules: git.DefaultSubmoduleRecursionDepth,

in CloneOptions

when using nixos-rebuild i also need to specify --flake '.?submodules=1', not sure how that translates to the way you build.

this should probably be behind an extra option that defaults off, or maybe a generic option for extra build arguments?