what's the point here?

[matti]

we use loopback 3 because it's a declarative way to build an API with the loopback json - with next/4 it's no longer supported.

I'm having hard time seeing what's the purpose for this?

[raymondfeng]

The declarative way will be added. We're building up LB 4 incrementally, starting with the programatic approach. Please see some of the design notes at http://loopback.io/doc/en/lb4/Crafting-LoopBack-4.html. Thank you for being patient :-).