Technology

Apache Gravitino

A unified metadata lake — "catalog of catalogs" — that federates Iceberg, Hive, Kafka, and file-based data sources into a single governance layer. Apache incubating project.

7 connections3 resources3 posts

Summary

What it is

A unified metadata lake — "catalog of catalogs" — that federates Iceberg, Hive, Kafka, and file-based data sources into a single governance layer. Apache incubating project.

Where it fits

In environments with multiple catalogs (Glue, Hive Metastore, Polaris, Unity), Gravitino sits above them all, providing a unified metadata view. Engineers discover and govern data from a single pane regardless of which catalog or storage layer holds it.

Misconceptions / Traps
  • Gravitino does not replace individual catalogs — it federates them. You still need Polaris, Glue, or Unity underneath.
  • Lineage features are still maturing. Production lineage workflows may need supplementation with OpenLineage/Marquez.
Key Connections
  • implements Iceberg REST Catalog Spec — exposes federated metadata via the standard REST interface
  • enables Apache Polaris — can federate Polaris alongside other catalogs
  • solves Vendor Lock-In — unified view across multi-vendor catalog environments

Definition

What it is

A unified metadata lake — a "catalog of catalogs" — that provides a single governance layer across Iceberg, Hive, Kafka, and file-based data sources. Originally developed by Datastrato, graduated from Apache Incubator to a full Apache Top-Level Project in June 2025.

Why it exists

Enterprises run multiple data catalogs (Glue, Hive Metastore, Unity Catalog) across different environments. Gravitino federates these into a unified metadata view so engineers can discover and govern data from a single pane regardless of which catalog or storage layer holds it.

Primary use cases

Federated metadata management across hybrid and multi-cloud environments, unified data discovery, cross-catalog governance.

Connections7

Outbound7
scoped_to2
S3Table Formats
implements2
Iceberg REST Catalog SpecCatalog-Centric Control Plane
enables2
Apache IcebergApache Polaris
solves1
Vendor Lock-In

Resources3

DocsHigh
gravitino.apache.org/

Official Apache Gravitino project site covering the unified metadata lake architecture and multi-catalog federation.

GitHubHigh
github.com/apache/gravitino

Source repository with architecture documentation, integration guides, and release history.

BlogMedium
www.reddit.com/r/dataengineering/comments/1nuj7jq/we_just_sh...

Community discussion of the Gravitino 1.0 release covering real-world adoption considerations and comparisons to Unity Catalog.

Featured in

2026-09-26When the Catalog Started Handing Out KeysSeptember 2026 turned the lakehouse catalog into an agent-callable control plane and, in the same motion, into the thing holding your object-storage credentials. OpenMetadata 2.0 ships MCP on by default and rebrands as a context layer. Unity Catalog 0.6.0 quietly expires tokens that were previously valid forever and re-keys its credential cache. And CVE-2026-34214 showed what the failure mode looks like in production: a query engine handing bucket keys to anyone with SQL write privilege. Three facts, one boundary.2026-08-12When the Paper Trail Stopped Matching the SoftwareTwo real concurrency bugs surfaced in Apache Iceberg's own issue tracker. A year-old governance milestone sat uncorrected on a catalog page. A vector database's supposed major-version jump turned out to be a misread dev-build tag. This index runs on citations — so a week spent checking hundreds of them against primary sources is itself the story.2026-06-10The Catalog Became the Control Plane — for Humans and Agents AlikeWithin one quarter, Apache Polaris, Unity Catalog, and Apache Gravitino all converged on the same role: the catalog is no longer where you look up where a table lives — it's where access is granted, credentials are minted, query planning happens, and AI agents are let in or kept out. The companion shift to 'the catalog is becoming a database': the catalog is also becoming the control plane.