Not as far as I can tell. Web Functions let you configure concurrency, maximum environment count, and request rate limits, but there's no setting for how long an environment stays alive after its last request. The configurable timeout applies to individual requests, not the environment itself.

I measured between 5 and 7 minutes of idle time (after the last request had ended) across six environments. I was able to cut this short by exiting the process myself, but AWS records this as a runtime error so IMO it's not suitable to rely on in production.

Here's the AWS scaling documentation. I'm happy to be corrected if I missed anything.

https://docs.aws.amazon.com/lambda/latest/dg/web-functions-s...