So that

  pkg = linuxManualConfig {
    inherit stdenv;
    inherit (linux_mptcp_94) src version modDirVersion;

    # we need this to true else the kernel can't parse the config and
    # detect if modules are in used
    allowImportFromDerivation = true;

    shellHook = ''
      touch .scmversion
      echo "hello boss"
    '';
  };

works for instance.

Motivation for this change

Things done

• Tested using sandboxing (nix.useSandbox on NixOS, or option sandbox in nix.conf on non-NixOS)
• Built on platform(s)
  • NixOS
  • macOS
  • other Linux distributions
• Tested via one or more NixOS test(s) if existing and applicable for the change (look inside nixos/tests)
• Tested compilation of all pkgs that depend on this change using nix-shell -p nox --run "nox-review wip"
• Tested execution of all binary files (usually in ./result/bin/)
• Determined the impact on package closure size (by running nix path-info -S before and after)
• Fits CONTRIBUTING.md.