https://techcrunch.com/2019/04/24/databricks-open-sources-delta-lake-to-make-data-lakes-more-reliable/

Databricks, the company founded by the original developers of the Apache Spark big data analytics engine, today announced that it has open-sourced Delta Lake, a storage layer that makes it easier to ensure data integrity as new data flows into an enterprise’s data lake by bringing ACID transactions to these vast data repositories.

Delta Lake, which has long been a proprietary part of Databrick’s offering, is already in production use by companies like Viacom, Edmunds, Riot Games and McGraw Hill.