I've seen that situation as well. My approach recently has been to build things where running on Lambda is a feature, and not so much an architectural decision.

I've seen that situation as well. My approach recently has been to build things where running on Lambda is a feature, and not so much an architectural decision. The aws-serverless-express library basically wraps an express (or other similar framework) app to handle interfacing with the lambda, marshaling lambda "event" data into the framework request interface, for example.