# Preference pages

### Metamodel contributors

Xpand supports several types of meta-metamodels.

From older versions, the classic UML metamodels may be known. Currently also JavaBeans metamodels and EMF based metamodels are supported out of the box.

Additional metamodel contributors can be registered through an extension point.

The editors need to know with what kind of metamodels you are working. Therefore, one can configure the metamodel contributors on workspace and on project level.

### Global preferences

If you work always with the same type of metamodels, you can specify the metamodel contributors in the global preference page. It is available under Windows --> Preferences in the Xtend/Xpand section.

### Preferences per project

In the project property page there is also an Xtend/Xpand section available.

Therein you can enable the Xtend/Xpand nature (see below) and set project specific metamodel contributor settings.