Node.js isn't really a usecase that dictates what datastore you should use, it's just a certain way of writing a totally different piece of your app. In most n

Node.js isn't really a usecase that dictates what datastore you should use, it's just a certain way of writing a totally different piece of your app. In most node.js apps, the best answer is probably a SQL database. Sorry. If you're working with timelines or other cases where Redis's data models can help you, consider it, though beware that if your data is large, things will get more expensive fast since you're keeping everything in RAM. HBase, Cassandra, and Riak are all reasonable in similar cases and have their own tradeoffs. And yes, Couch fits a similar niche as Mongo. You might even be able to use something simpler like BerkeleyDB (quite mature) if you think you want a document store. RethinkDB may be a nice choice too. It's fairly young but looks like it's going good places. But your choice should be mostly dependent on what kind of data you're storing and what kind of guarantees and access models you need. It should not be based on someone on HN telling you "Riak is the best NoSQL database for Node.js" because their idea of what most Node apps need may not be what yours needs.