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   load
 ```
 
+## Use
+
+Carrefour links entities in a FAST model to entities in a Famix model.
+It is composed of 2 parts:
+- Carrefour meta-model
+- Binder
+
+Steps:
+1. Generate the FAST model of a Famix entity (eg. a FamixMethod)
+2. Bind the nodes in the FAST model to entities in the Famix model with method `#bindFASTModel`
+
+### Carrefour meta-model
+
+Does not do much, "import" entities from *language dependent* Famix meta-model and *language dependent* FAST meta-model and adds relations between them.
+
+### Generating the FAST model
+
+Done by a *language dependent* parser.
+Each FamixEntity should know how to do it by implementing `#getFASTModel`
+
+### Binding
+
+Done by visiting the FAST model (an AST).
+Again needs a *language dependent* visitor.
+
+For Java, there are 2 methods:
+- `#bindFastModel:fromFamixMethodEntity:` that visit root *method* of the FAST model
+- `#bindFastModel:fromFamixClassEntity:` that visit root *class* of the FAST model
+
+
 ## Developers
 
 ### Update tests