I'm a big fan of Rich's work and I like (the idea of) Datomic a lot and while I don't begrudge their decision to keep it closed source, I personally won't use a

I'm a big fan of Rich's work and I like (the idea of) Datomic a lot and while I don't begrudge their decision to keep it closed source, I personally won't use a database that isn't open source. Its simply too important a piece of any modern software and having only one company that can make fixes or changes if you need something is too risky for my taste. My priorities won't always align with Cognitect's, but if they're the only ones that can provide support, fixes or features then that is too much risk for me. Having said that, I don't know what the solution is. A Red Hat model would be great, but how many companies have managed to replicate that success? The usual "commercial gives you these extra features" model means you need non-critical but nice-to-have features that people want to pay for but that doesn't cripple the open source version, not exactly ideal either. Having paid support and consulting as the primary income seems difficult too (eg RethinkDB). So, perhaps keeping it closed is the best route for them, I just wish there were better options. Oh well, I still get to enjoy the majority of Rich & team's work, so I'm not complaining. > If Ions is successful enough that could be their profit source, allowing them to set standalone Datomic free. That would be a great future.