Thanks for the detailed response. I hope to learn from your experiences.

AMQP is indeed a complicated protocol so I can appreciate your reluctance to write a client.

The failure mode I was referring to with Redis is that you now have additional custom code which pulls from Redis and inserts to RabbitMQ. This is another process that can fail, and some of those failure modes could result in duplicate or lost messages. For example, agentredrabbit could shutdown in an unclean way where the "dump" file doesn't get written. Also, you didn't mention if you're using Redis in AOF or RDB persistence mode, but in RDB it only writes to disk occasionally so you could lose messages there. Also, if agentredrabbit fails then Redis could run out of memory (RabbitMQ automatically writes to disk once memory limits are exceeded).

I will believe that writing to Redis is /always/ faster than writing to RabbitMQ, but I'd really like to know what other things you guys tried to make RabbitMQ actually work for you. Did you experiment with queue settings? Memory limits? Erlang tweaks? SSDs? What was it about shovel that didn't work the way you wanted it to? I'm working towards what I hope will be a pure RabbitMQ infrastructure so knowing what you've tried and didn't try will be informative.

Thanks.