Postgres transactions can also take as long as they want and the results will never be inconsistent. The downside to SERIALIZABLE is that conflicts become visi

Postgres transactions can also take as long as they want and the results will never be inconsistent. The downside to SERIALIZABLE is that conflicts become visible failures to the client, so you have to handle them and retry. Datomic solves this by serialising through the function you pass, but at great latency cost.