Use the lambda layer [0] it sends the telemetry after the response is sent, so it doesn’t block.

[0] https://github.com/open-telemetry/opentelemetry-lambda

This is what I have done with CLI apps the directly send to the OTEL vendor. It works great.

I don't use Lambda anymore, but yes. I submitted traces to AWS XRay in a background goroutine with a small timeout.