> My big problem with lambda / serverless is the developer experience is pretty awful. The time between making a change, deploying, and seeing the result of that change is slow. You can work around this (with tools like localstack), but it's often not close enough to the real environment. You'll still waste tons of time debugging permissions issues when you do a real deploy.

I haven't had much of a problem. Once I figure out the shape of the inbound payload, it's pretty easy to test locally. I can't think of any reason the runtime environment would be an issue. Debugging IAM is tedious, but I just created one Terraform module that I use for all of my functions so I don't have to slog through the IAM stuff every time I make a function.