This is a good reference document for myself as I begin to think about how I want to write the next generation gRSShopper. It outlines a basic startup server configuration using a Linux OS, Redis database, Nginx server and Node.ja applications, with backup/sync on Amazon S3. I've looking at architecture B. Since this is in essence a personal application, it shouldn't need to scale beyond that (though there are scaling options if I'm wrong). For a messaging backend, maybe MatterBridge?