docs: $allowNull

joelgallant · joelgallant · commit 1526ed224434 · 2021-02-22T09:02:55.000-07:00
diff --git a/docs/guide/intro/extensions.md b/docs/guide/intro/extensions.md
@@ -115,6 +115,8 @@ username:
     $fallback: 'no-user'
 ```
 
+Use `$allowNull: true` if your fallback is allowed to be nullable.
+
 ## Decryption
 
 Values that are encrypted will automatically be decrypted.
