5.2. API and Backwards Compatibility

The BPMS 6 system provides backward compatibility with the rule, event and process interactions from BRMS 5. You should eventually migrate (rewrite) these interactions to the all new revamped core API because this backward compatibility is likely to be deprecated.
If you can't migrate your code to use the new API, then you can use the API provided by the purpose built knowledge-api jar for backwards compatible code. This API is the public interface for working with BPMS and BRMS and is backwards compatible.
If you are instead using the REST API in BRMS 5, note that this has changed as well and there is no mechanism in it for backwards computability.