There are as many sync/async options for Couch map reduce as you could possibly need. The key is for some of the patterns to work, you need to be able to know

There are as many sync/async options for Couch map reduce as you could possibly need. The key is for some of the patterns to work, you need to be able to know your index queries come from the same database snapshot as your event feed, which is easier to do when you aren't in clustered mode.