The problem I have is: build a scalable backend API decoupled as much as possible from the frontend. And more in general, to build a Web application using some kind of frontend. I would like to compare mainly Liferay with Spring Boot
The most important factors for me are: scalable backend, API documentation, TDD, integration with frontend application for modern reactive interaction
It's a general development question, be more specific, because /dev/std... is a generic approach, not a targeted development. You want to develop PHP or Java? Both are good in their terms, but it's your decision. For PHP Laravel is a robust and exhaustive console enabled framework, featuring rich integrations with virtualization & REST. On the other hand, Spring will bring you learning curve if you are switching from PHP and so on. Try to match your needs with project requirements, it will be easier.