Blaze implements the RESTful FHIR API and claims its capabilities in a CapabilityStatement.
A current CapabilityStatement can be fetched from https://blaze.life.uni-leipzig.de/fhir/metadata (user/password: demo)
The state of the implementation of CQL can be found here.
Touchstone test results can be found here.
Crucible test results can be found here: Blaze