JS migration guide

js/README.md

@@ -189,6 +189,13 @@ Example of building a Turtle file from the named graph `<http://example.com/grap
 store.dump("text/turtle", oxigraph.namedNode("http://example.com/graph"));
 ```
 
+## Migration guide
+
+### From 0.2 to 0.3
+* The `MemoryStore` class is now called `Store` (there is no other kind of stores...).
+* RDF/JS datamodel functions (`namedNode`...) are now available at the root of the `oxigraph` package. You now need to call `oxigraph.namedNode` instead of `store.dataFactory.namedNode`.
+* [RDF-star](https://w3c.github.io/rdf-star/cg-spec) is now implemented. `Quad` is now a valid value for the `Ωuad` `subject` and `object` properties.
+
 ## How to contribute
 
 The Oxigraph bindings are written in Rust using [the Rust WASM toolkit](https://rustwasm.github.io/docs.html).