One thing I could not find in the write-up is the change in the expense. Did serverless save any money, compared to always-up VMs? Did much of their load run under the free tier limits?
Serverless shines when the load is very spiky, and you can afford high long-tail latency. Then you don't pay for all that time when your server would be idling. (This is usually not the case for auth APIs, unless they auth other infrequently invoked operations.)
Serverless shines when the load is very spiky, and you can afford high long-tail latency. Then you don't pay for all that time when your server would be idling. (This is usually not the case for auth APIs, unless they auth other infrequently invoked operations.)