sonic: fix install step on Darwin

    "CC=${stdenv.cc.targetPrefix}cc"

  ];

  env = lib.optionalAttrs stdenv.hostPlatform.isDarwin {

    # Ensure that there is enough space for the `install_names_tool` to update

    # the install name of the output library.

    NIX_LDFLAGS = "-headerpad_max_install_names";

  };

  nativeBuildInputs = [ installShellFiles ];

  buildInputs = [ fftw ];