There's a gap between what we can do well within Nix builds and other stateful ~project-management tasks that people need to do if Nix is a critical part of their project.
Because Nix doesn't cover these cases gracefully/fluently, there's an awkward liminal zone on the project where even though they've bothered nailing down all of their preconditions for the .nix builds, they still have things like Makefiles that use dependencies they need to provide. So they're either weirdly invoking make inside a Nix shell, or they're using invoking nix-shell/run a dozen times inside the Makefile.
So I wondered if there's good case for like a nix-make/nix make core command/util that interprets a nix-shell or nix-shell-esque shebang specifying the Makefile's dependencies and supplies them before invoking gnumake/bin/make.