Why store a hashmap?

[evbo]

Why not just fetch the appconfig from the lambda extension on each execution? Isn't it possible that your hashmap contains stale config? The fetch over localhost isn't that much overhead is it?

[ymwjbxxq]

You are right, and it could be stale.
My goal was to avoid the call on the extension because it can be costly. For me, AppConfig became one of the most expensive services in a serverless application.

It is a tradeoff, and it depends on the use case. I did not have a case where the configuration changed so often, and when it did, I would deploy the Lambda to avoid stale data (not the best)