Hi, if I understand your plans regarding Tapestry 5.4 correctly, you uncoupled the JavaScript engine so that you can choose between e.g. Prototype or JQuery.
Now, after asking some question on StackOverflow: http://stackoverflow.com/questions/29645744/how-do-i-deploy-my-eclipse-tapestry-web-app-project-previously-running-in-an-emb I wonder if it would be possible to do the same with the bytecode manipulation. A layer so that javassist or ASM Plastic would be choosable. If that is feasible, I don't know how or when the bytecode manipulation is achieved. Regards, Daniel P.