The issue with lambda is that at high loads it's a lot more expensive than using a server. I looked into doing something with lambda that would take about ~10b

The issue with lambda is that at high loads it's a lot more expensive than using a server. I looked into doing something with lambda that would take about ~10b invocations/day and it was so expensive compared to just standing up a microservice. So I've never deployed a lambda before and I'm sure at low loads it's fine, but I would be afraid of taking a dependency on lambda/functions in an application architecture.