If my actor crashes and the message hasn't been written to a write ahead log, the message would be lost since it's not easy to resume the processing of the mess

If my actor crashes and the message hasn't been written to a write ahead log, the message would be lost since it's not easy to resume the processing of the message received without persisting it somewhere. I am not that familiar with Erlang's supervision hierarchies. You could do something similar to ActiveMQ and rebroadcast a message until it is acknowledged.