Unity Catalog (https://github.com/unitycatalog/unitycatalog 3,550 ) is the open-source edition of the catalog behind Databricks 2,717 , open-sourced in June 2024 and now a sandbox project of the LF AI & Data Foundation (Apache-2.0, a Java server, 0.6.0 on 20 August 2026). Its namespace (catalog.schema.object) holds tables, volumes (governed folders of files), functions, views and machine learning models. Delta Lake 237,929 is native; Iceberg 129 clients read through its Iceberg REST API and UniForm metadata (UniForm). Version 0.6.0 added Spark 4.2 129 support and metric views.
It is not the Databricks product (Databricks), which adds lineage, attribute-based access control and auditing, and sandbox is the foundation's earliest stage. It is not run here, since BookNest is Iceberg-first; it suits Delta-first teams who want tables, files and models under one set of grants.