Running an ASP.NET app in AWS Lambda is just a few lines of code. However, all of a sudden startup time becomes important for both performance and cost.
These investments by Microsoft and others[1] allow .NET to remain relevant and viable for modern use cases.
I get that the machinery under the hood is different (ie. Kestrel web server may not get used). However, we typically don’t care about those details. Our ASP.NET code runs in 3 separate places (containers, servers, Lambda) and the only difference between all 3 is a single entry point file.
Do you mean because Lambda is only serving one request at a time and has a more ephemeral host process lifetime?
Yes, a typical hosted ASP.NET app is neither ephemeral or one request at a time. So this drives different design decisions.