The Microprofile Fault Tolerance TCK uses the Hamcrest library for some of its assertions. We are using the TestNG container which doesn't automatically include the Hamcrest classes (whereas I think the JUnit container does).
I ended up adding an extension to add an auxiliary jar with all the hamcrest classes: https://github.com/eclipse/microprofile-fault-tolerance/pull/370/files
Is this the most sensible way of solving this problem or am I missing something better?