Delayed Abandon

[lukeschafer]

Delayed abandons would be useful for retry backoffs. E.g. instead of

await message.AbandonAsync(exception.ExceptionDetailsAsProperties(_clock.UtcNow));

you can

If (_settings.DelayedAbandon.HasValue) Thread.Sleep(_settings.DelayedAbandon.GetValueOrDefault());
await message.AbandonAsync(exception.ExceptionDetailsAsProperties(_clock.UtcNow));

It's safe (durable) to wait in-proc like this as a) it's already on its own thread, and b) if the process dies the peeklock will simply expire and the message will become available again

Optional:

Exponential backoffs - when abandoning a message, use DeliveryCount, or add the last-waited/abandon count to the message properties and read this when backing off.

Happy to implement everything above if you agree.

[lukeschafer]

clearly the max wait time is the peeklock time :)