diff --git a/default.nix b/default.nix
index dfc91b2..0664728 100644
--- a/default.nix
+++ b/default.nix
@@ -39,7 +39,10 @@ let
         source = mkOption {
           type = nullOr (either path str);
           default = null;
-          description = "Path of the source file or directory - be sure to quote paths you don't want nix to copy to the store.";
+          description = ''
+            Path of the source file or directory.
+            Be sure to quote paths you don't want nix to copy to the store.
+          '';
         };
 
         executable = mkOption {