I imagine the following would be needed..
1) Spring MVC like library for interfacing with HTTP requests.
2) DB ORM or ORM like. DB libraries for any possible DB.
3) centralized logging. e,g, Logback that forwards all logs to ELK.
4) Dependency injection.
5) Versatile configuration system. Similar to Spring configurations.
6) AWS SDK.
7) Commons like libs like Guice or Apache Commons.
stuff like that.