rest VS Grails

There are very few frameworks that I would personally recommend: the Servlet API and JAX-RS are pretty much the only ones I consider decent. I personally avoid JAX-RS because of https://github.com/jakartaee/rest/issues/468 and because you can replace most of its functionality using ~5-10 custom classes.

Have you never used the Servlet API? JPA? Those validation annotations from the javax.validation package? JAX-RS to define REST Endpoints? CDI for dependency injection?

Take a look at https://github.com/jakartaee/rest/issues/468

And frameworks like Grails build conventions and helpers on top of Spring.

I don't have any direct experience and am only suggesting it because you mentioned RoR...But Grails (https://grails.org/) is basically the JVM version of RoR (Groovy on Rails -> Grails).

Grails - Spring under the hood. Much less boilerplate. Opinionated, which helps keep things consistent. Uses Spring-Security plugin for authentication.

Also, Grails, which a Rails like framework build on Groovy, a JVM scripting language.

Any JVM language to the rescue here? There’s one, but it’s not the one you’re thinking about. In a sign that this index may not accurately reflect our project reality, Groovy saw a meteoric rise of 0.86% to 1.04% last year! That was good for place 17. Yep, Groovy! Are people writing Gradle plugins in Groovy? Or is Grails having a resurgence? I’m as baffled as you are.