Honestly, I've had a much much easier time managing periodic tasks by executing them in AWS Lambda or Fargate

Not a good idea to have sw tightly coupled to a Cloud service.

Correct, which is why Lambda and Fargate are nice. My Lambda entry points are developed in terms of Java IO streams (usually wrapped into Okio streams). My Fargate containers are developed in terms of Docker (which, yes, is coupled to ECS until the EKS counterpart is released). It’s very very easy to decouple your applications through interfaces instead and utilize cloud services for deployment