automatic hot reload when the source code changes,

lambdas as handlers - with named and type-safe parameters,

URI path patterns (simple and regex-based),

Admin Center for convenient management of the deployed app,

JVM and OS metrics in the Admin Center,

info about the web app routes in the Admin Center,

role-based web security with out-of-the-box login / logout,

configuration info in the Admin Center,

configuration profiles,

improved dependency injection (with profile support),

easy JPA bootstrap with TX management and nice utils like JPA.insert(new Foo()) ,

redesigned and enhanced JDBC utils,

scaffolding of JPA entities (RESTful services and management GUI),

new templating language and engine - similar to Mustache, but more practical,

highly customizable setup (serialization, security, error handling, template engine…​),