By David Mytton, CEO & Founder of Server Density. Published on the 28th September, 2011. Update Nov 2015: – We have since reached the limits of MongoDB’s atomic findAndModify and have moved over to using Kafka for queuing. Back in April we ditched RabbitMQ in favour of building our own simple queuing system using MongoDB. This has been in production since then and has been working very well. Last