[phamilton]

I've explored this space pretty thoroughly, including the Dynamo approach you've described. Dynamo does not have a strict guarantee on when items get deleted:

  TTL typically deletes expired items within a few days. Depending on the size and activity level of a table, the actual delete operation of an expired item can vary. Because TTL is meant to be a background process, the nature of the capacity used to expire and delete items via TTL is variable (but free of charge). [0]

Because of that limitation, I would not use that approach. Instead I would do Scheduled Lambdas to check for items every 15 minutes in a Serverless Aurora and then add them to SQS with delays.

I've had my eye on this problem for a few years and keep thinking that a simple SaaS that does one-shot scheduled actions would probably be a worthy side project. Not enough to build a company around, but maintenance would be low and there's probably some pricing that would attract enough customers to be sustainable.

[0] https://docs.aws.amazon.com/amazondynamodb/latest/developerg...