diff --git a/spacemk/commands/generate.py b/spacemk/commands/generate.py
index 34f5914..b8b4109 100644
--- a/spacemk/commands/generate.py
+++ b/spacemk/commands/generate.py
@@ -13,8 +13,8 @@
 )
 @pass_meta_key("config")
 def generate(config):
-    def default(value, default):
-        return value if value is not None else default
+    def default(value, _default):
+        return value if value is not None else _default
 
     generation_config = {
         "spacelift": {