Update README.md

README.md

@@ -8,6 +8,14 @@ An open-source communication stack implementation of OPC UA (OPC Unified Archite
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+### What is currently working?
+The project is in an early stage. We retain the right to break APIs until a first stable release.
+- Binary serialization of all data types: 100%
+- Node storage and setup of a minimal namespace zero: 100%
+- Standard OPC UA Clients can connect/open a SecureChannel/open a Session: 100%
+- Browsing/reading and writing attributes: 100%
+- Advanced SecureChannel and Session Management: 75%
+
 ### Documentation
 Documentation is generated from Doxygen annotations in the source code. The current version can be accessed at [http://open62541.org/doxygen/](http://open62541.org/doxygen/).