Datomic is a database of flexible, time-based facts, supporting queries and joins, with elastic scalability, and ACID transactions. Datomic can leverage highly-available, distributed storage services, and puts declarative power into the hands of application developers.
Database as an immutable data structure, powerful query abilities, time travel are all amazing features.
What do you dislike?
It's not open source, so it's not feasible tech to use for a product's core infrastructure, seeing what happened to other proprietary databases when they get bought out. Licensing model also makes deployment rather inconvenient and full of questionable implications for distribution (i.e. are we allowed to put it up in a docker container on docker hub? does that count as distributing it without permission?).
What business problems are you solving with the product? What benefits have you realized?
We've mostly been using it for a few early prototypes using Clojure & ClojureScript, and the immutable database semantics fits perfectly with the language. Unfortunately we decided to go with Postgres in the end due to licensing concerns.
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