AssertJ VS piranha

Maybe not the feedback you want, but would you consider developing something that looks like plain old (and frankly beautiful) AssertJ?

AssertJ - fluent assertions

AssertJ https://github.com/assertj/assertj

Truth or AssertJ for easier assertions in tests with better exceptions

While we are at it: AssertJ is very powerful for writing assertions.

In OO you can make beautiful DSLs that allow really declarative use within that domain, e.g. test assertions in AssertJ, but everybody in the OO world is sensible enough to not try and claim OO as such being declarative. I guess they don't feel a need to try to prove the superiority of the paradigm.

AssertJ comes with a variety of assertions that can be chained together and are specific to the type of your "actual" variable.

At any rate it comes from a library called assertj.

While Hamcrest add some fluentidity to unit tests ä, I prefer the fluent assertions of AssertJ.

You can still mix and match APIs at will with EE. This is what you do on Tomcat mostly, but also with Piranha Cloud (https://piranha.cloud), and to a degree even with Open Liberty.

Not necessarily. Piranha Cloud is an implementation of the Servlet API that is not a container.

Piranha Cloud uses the Java Module system extensively. See https://piranha.cloud