[babbledabbler]

Breaking things into tiny functions and putting them on many different servers incurs tradeoff costs in both complexity and compute. There is a complexity cost in having to deal with the setup, security, and orchestration of those functions, and a compute cost because if the overall system is running constantly it will be less efficient and therefore more expensive than running on one box.

[makkes]

I agree on the tradeoffs you have to make. The main cost driver here was storage and traffic, though.

[babbledabbler]

Good point. "communication" should also be on the list. I don't think storage is technically the tradeoff in this case even though it's S3. It's the traffic between those components that's costing them.