whichdb
vs

immudb vs XTDB

immudb: Immutable, tamper-evident database with cryptographic proofs, offering key-value, SQL and document APIs. XTDB: Bitemporal SQL database on object storage that keeps every version of every row.

key differences

  • immudb is primarily a ledger database; XTDB is relational.
  • Licensing: immudb is source-available (Business Source License 1.1); XTDB is open source (copyleft) (Mozilla Public License 2.0).
  • Horizontal scaling is none in immudb and manual in XTDB.
  • Only immudb has secondary indexes, role-based access.
  • Only XTDB has columnar storage, compression.
  • immudb can run embedded in your application process.

choose immudb for

  • +Tamper-evident audit logs
  • +Replacing Amazon QLDB with a self-hosted ledger
  • +Software supply-chain and compliance records

best at · Ledger, OLTP, Event sourcing

choose xtdb for

  • +Financial and insurance systems needing as-of reporting
  • +Audit trails with retroactive corrections
  • +Event-sourced systems wanting SQL over history

best at · OLTP, Event sourcing, Ledger

immudbImmutable, tamper-evident database with cryptographic proofs, offering key-value, SQL and document APIs.
XTDBBitemporal SQL database on object storage that keeps every version of every row.
overview
Primary model
Ledger
Relational
Also supports
Key-Value, Relational, Document
Document, Columnar / OLAP
Type
Database engine
Database engine
Status
Active
Active
Developer
Codenotary, Inc.
JUXT Ltd
First release
2020
2019
Latest version
1.11.2 (Sep 3, 2026)
2.2.0 (Oct 21, 2026)
License
Source-availableBusiness Source License 1.1
Open source (copyleft)Mozilla Public License 2.0
Free tier
✓
✓
popularity
WhichDB Score
17.2
8.3
Rank
#193
#328
GitHub stars
9K
3.1K
Stack Overflow questions
3
7
scale & guarantees
Comfortable data size
Medium (≤ 10 TB)
Medium (≤ 10 TB)
Horizontal scaling
None
Manual
Multi-region
Read replicas
None
ACID
Full
Full
Consistency
Strong
Strong
Schema
Flexible
Flexible
Architecture
Client server, Embedded, Primary replica
Distributed, Shared storage
deployment
Self-hosted
✓
✓
Vendor-managed cloud
—
—
Serverless
—
—
Embedded
✓
—
Edge
—
—
Clouds
–
–
capabilities
Transactions
✓
✓
Joins
✓
✓
Secondary indexes
✓
—
Full-text search
—
—
Vector search
—
—
Geospatial
—
—
JSON
✓
✓
Change data capture
—
—
Triggers
—
—
Stored procedures
—
—
Materialized views
—
—
TTL / expiry
—
—
Pub/Sub
—
—
Columnar storage
—
✓
In-memory
—
—
Durable persistence
✓
✓
Compression
—
✓
Encryption at rest
—
—
Role-based access
✓
—
Time travel
✓
✓
Branching
—
—
Online schema changes
—
—
Streaming ingest
—
—
Offline sync
—
—
Runs in WebAssembly
—
—
interfaces
Query languages
SQL (immudb dialect), Key-value API
SQL, XTQL
Client languages
Go, Java, Python, Node.js, .NET
Java, Kotlin, Clojure, Python, JavaScript, Go
Best for
Ledger, OLTP, Event sourcing
OLTP, Event sourcing, Ledger, HTAP
Add more to this comparisonNot sure either fits? Try smart match

immudb vs XTDB: FAQ

What is the difference between immudb and XTDB?

immudb: Immutable, tamper-evident database with cryptographic proofs, offering key-value, SQL and document APIs. XTDB: Bitemporal SQL database on object storage that keeps every version of every row. immudb is primarily a ledger database; XTDB is relational. Licensing: immudb is source-available (Business Source License 1.1); XTDB is open source (copyleft) (Mozilla Public License 2.0). Horizontal scaling is none in immudb and manual in XTDB.

When should I choose immudb over XTDB?

Choose immudb for tamper-evident audit logs; replacing Amazon QLDB with a self-hosted ledger; and software supply-chain and compliance records. Choose XTDB for financial and insurance systems needing as-of reporting; audit trails with retroactive corrections; and event-sourced systems wanting SQL over history.

Is immudb or XTDB more popular?

immudb ranks #193 on the WhichDB Score (17.2/100) and XTDB ranks #328 (8.3/100). Popularity is not fit: check the requirements that matter for your project.

Are immudb and XTDB open source?

Not in the OSI sense. immudb is source-available: you can read the code, but the license restricts some uses, typically offering it as a competing managed service. License: Business Source License 1.1. Yes. XTDB is open source. License: Mozilla Public License 2.0.