If they had used an ALB instead of API Gateway, the cost might well have been a 2x increase, especially given that would replace the ELB they're already using. The ALB option has it's own caveats though...
Yeah, that would have been a much better fit. I just didn't know you could put ALB in front. (Also, a "load balancer" in front of serverless... , and yes I know load balancer do more than load balance.)
I mainly went with API Gateway since that's the default setup the serverless framework uses.
For AWS it was november 2018 when it was annanced. Still a pretty new thing if you ask me. Many Cloud Architects still dont understand all pros and cons of this solution.
One con is that using an application load balancer with lambda restricts you to 1MB requests (and responses?) as opposed to 10 with APIGW. Lambda itself has a 6Mb limit.
