OMG QVT is an extension of OMG OCL, and Eclipse QVTd is an extension of Eclipse OCL. The reused metamodels and Xtext grammars result in a very tight coupling between Eclipse QVTd and Eclipse OCL.
The QVTr to QVTc to QVTu to QVTm to QVTp via QVTs to QVTi transformation chain uses Epsilon as a bootstrap. Epsilon is a mature Eclipse project not availlable in the Simultaneous Release. Epsilon plugins are therefore hidden as internal libraries in the release. These can be eliminated once the transformation chain is rewritten using QVTr.