> it's going to cost me close to nothing
Until it does and then you are screwed without an easy way to get out if your application is anything else than trivial. It has it's uses; a simple page/site which won't get any users and a system that needs to elastically scale forever, but in between, you are just burning (your company) money for no reason other than HN said it is the best (a lot of people here are working at FAANG; it's baffling why anyone would take any advice from architecture ran at a company with 100k more employees than their own startup with all this cloud / devops garbage and resulting costs and headaches).
I’m not sure I understand this argument. Anything that runs in a lambda can also be run outside of a lambda. You just need to give yourself a way to invoke it or access it.
One setup I’ve used with a previous client was deploying many FastAPI lambdas, wrapped in Mangum. You can even in the same code base expose both. This way, you can deploy to a container and a lambda without changing any code.
In one case, we used APIGWv2 to give the lambda an HTTP endpoint, in the other, it’s the container that provides it. You can throw in IPv6 support by having a CF distro in front of both.