XTDB
XTDB is an immutable SQL database for systems that need historical records, reporting, or auditability.
What XTDB is
XTDB is an immutable SQL database for systems that need historical records, reporting, or auditability. It records bitemporal history, letting users query both when data was valid and when the system recorded it. SQL:2011 temporal queries are supported, along with a broader SQL dialect through FlightSQL and PostgreSQL wire compatibility. XTDB handles flexible schemas and semi-structured data, and supports PostgreSQL-compatible SERIALIZABLE SQL transactions with optimistic concurrency. Its object-store LSM-tree design and use of Apache Arrow support temporal analytics and scale-out compute. Deployment options include Docker, on-premises installations, and cloud marketplaces; Apache Kafka can be used as a message log, with Kafka Connect for external sources. Authentication can use a root user, a configured user list, or OpenID Connect providers. XTDB is open source under the MPL license and free to use. The free Partner Pack is free; Developer Edition is $2,000 a year.
Good
- Queries data across valid and system time.
- Supports SQL:2011 temporal queries.
- Offers Docker and on-premises deployment.
- Open source under the MPL license.
Watch out
- Developer Edition costs $2,000 a year.
- Production Support has no listed price.
Who it suits
XTDB may suit developers augmenting existing systems or building applications that need auditable historical state. It is also relevant to teams that need temporal SQL queries and flexible data schemas.
Verdict
XTDB centers on retaining and querying historical state, with SQL and multiple deployment options. Its free use and open-source license are distinct from the paid support plans.
Plans and prices
From XTDB's own pricing page, checked 7 Oct 2026.
| Plan | Price | What it gives you |
|---|---|---|
| Partner Pack | Free | Community support · Private Zulip stream · Early access to releases · Feedback channel · Partner network · $0/year |
| Developer Edition | $2,000 a year | Partner Pack features · Official support · Private issue tracker · Upgrade guidance · UK business hours response SLA · $2k/year |
| Production Support | Priced on request | Developer Edition features · Private release channels · Rapid hotfix service · Core team consultations · 24/7 SLA |
The facts
Each one read from XTDB's own pages, with the date it was checked.
What it does
- Audience
- The maker describes XTDB as useful for augmenting existing applications and building new applications that need auditability and historical state.checked 7 Oct 2026
- Authentication
- XTDB supports a single root user, a configured user list, and OpenID Connect authentication providers.checked 7 Oct 2026
- Bitemporal history
- XTDB records bitemporal history so users can query data across valid time and system time.checked 7 Oct 2026
- Deployment
- XTDB can run using Docker and is also available for on-premises deployment and through cloud marketplaces.checked 7 Oct 2026
- Integrations
- XTDB supports Apache Kafka as a message log and Kafka Connect as an external source.checked 7 Oct 2026
- License
- XTDB is free to use and open source under the MPL license.checked 7 Oct 2026
- Purpose
- XTDB is an immutable SQL database designed to simplify development, reporting, and compliance for systems that need historical records.checked 7 Oct 2026
- Schema
- XTDB supports flexible schema and first-class handling of semi-structured data.checked 7 Oct 2026
- SQL
- XTDB supports SQL:2011 temporal queries and a rich SQL dialect through FlightSQL and PostgreSQL wire compatibility.checked 7 Oct 2026
- Storage and compute
- XTDB uses an object-store LSM-tree design and Apache Arrow for temporal analytics and scale-out compute.checked 7 Oct 2026
- Support
- The maker offers annual production support subscriptions, community support, consulting, and training.checked 7 Oct 2026
- Transactions
- XTDB supports PostgreSQL-compatible SERIALIZABLE SQL transactions with optimistic concurrency.checked 7 Oct 2026
The company
- Headquarters
- London, United Kingdomchecked 28 Sep 2026
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