The main problem with building apps with a micro- mini- whatever-API based message architecture is speed, or the lack thereof. In order to make this happen, we have to jump through all kinds of architectural and infrastructure hoops.

Is your single API request that then cascades to 5, 10 or 15 micro-services calls on a message buss going to complete in under 400ms? No. It’s not. Not unless you have some rocking way overkill network behind you. Sure, AWS can do this with Lambda, but the cost and maintenance of the Frankenstein you just pieced together because of overkill decoupling just created a nightmare architecture.

Finally, REST is dead. Stop using it. It’s far too archaic and far too limiting. I’ve been using a form of JSON-RPC services for over a decade now and I’m never going back to REST.