README.md in smart_initializer-0.0.0 vs README.md in smart_initializer-0.1.0.alpha1

@@ -34,9 +34,27 @@
 end
 
 User.new(1, 'John', 'test123', role: :admin, metadata: {}, enabled: false)
 ```
 
+**Limitations**:
+
+- `param` has no :default option (at all);
+- last hash argument will be treated as `kwarg`s;
+
+**Type aliasing**:
+
+```ruby
+SmartCore::Initializer.type_alias(:hash, SmartCore::Types::Value::Hash)
+
+class User
+  include SmartCore::Initializer
+
+  param :data, :hash
+  option :metadata, :hash
+end
+```
+
 ---
 
 ## Contributing
 
 - Fork it ( https://github.com/smart-rb/smart_initializer )