diff --git a/pywal/__main__.py b/pywal/__main__.py
index 552b18b..7ca31bd 100644
--- a/pywal/__main__.py
+++ b/pywal/__main__.py
@@ -41,7 +41,7 @@ def get_args():
     arg.add_argument("--backend", metavar="backend",
                      help="Which color backend to use. \
                            Use 'wal --backend' to list backends.",
-                     const="list_backends", type=str, nargs="?")
+                     const="list_backends", nargs="?", default="default")
 
     arg.add_argument("--theme", "-f", metavar="/path/to/file or theme_name",
                      help="Which colorscheme file to use. \