immudb
activeby Codenotary, Inc. · since 2020 · also known as Codenotary immudb
Immutable, tamper-evident database with cryptographic proofs, offering key-value, SQL and document APIs.
Overview
immudb is an append-only database from Codenotary in which every write is recorded in a Merkle-tree-backed log. Clients can verify inclusion and consistency proofs themselves rather than trusting the server. It exposes key-value, SQL (with a subset of the PostgreSQL wire protocol) and document APIs, keeps full history so you can query data as of any earlier transaction, and runs embedded in Go or as a server. It is a practical self-hosted replacement for QLDB-style audit ledgers. The licence moved to BSL 1.1 from version 1.9DOM.2, so check the use grant before offering it as a service.
Strengths & trade-offs
Strengths
- +Client-verifiable cryptographic proofs that history was not altered
- +Time-travel queries over the full history of every key and row
- +Embeddable in Go or run as a server, self-hosted anywhere
- +SQL access through a subset of the PostgreSQL wire protocol
Trade-offs
- −BSL licence since 1.9DOM.2 restricts some hosted uses
- −Storage only grows; deletes are logical
- −SQL dialect and Postgres compatibility are partial
Great for
- +Tamper-evident audit logs
- +Replacing Amazon QLDB with a self-hosted ledger
- +Software supply-chain and compliance records
Think twice for
- −High-churn data that must be physically deleted (e.g. GDPR erasure)
- −General-purpose OLTP at large scale
Capabilities
Native or official first-party support · 7 of 25 tracked
Scale & consistency
- Comfortable data size
- Medium · ≤ 10 TB
- Horizontal scaling
- None
- Multi-region
- Read replicas
- Transactions
- Full ACID
- Consistency
- Strong
- Schema
- Flexible
- Architecture
- Client server, Embedded, Primary replica
- Query languages
- SQL (immudb dialect), Key-value API
Single primary with asynchronous or synchronous replicas.
Deployment
Ecosystem
Alternatives to immudb
AWS's serverless ledger database with a cryptographically verifiable journal, retired in July 2025.
immudb vs amazon-qldb →Purpose-built financial transactions database: double-entry accounts and transfers at very high throughput.
immudb vs tigerbeetle →Bitemporal SQL database on object storage that keeps every version of every row.
immudb vs xtdb →Immutable Datalog database from Nubank where every fact is timestamped and queries run in the app process.
immudb vs datomic →The extensible, standards-first open-source relational database.
immudb vs postgresql →Blockchain-style database combining MongoDB storage with Tendermint BFT consensus; dormant since 2020.
immudb vs bigchaindb →immudb FAQ
What is immudb?
immudb is a ledger database by Codenotary, Inc., first released in 2020. immudb is an append-only database from Codenotary in which every write is recorded in a Merkle-tree-backed log. Clients can verify inclusion and consistency proofs themselves rather than trusting the server. It exposes key-value, SQL (with a subset of the PostgreSQL wire protocol) and document APIs, keeps full history so you can query data as of any earlier transaction, and runs embedded in Go or as a server. It is a practical self-hosted replacement for QLDB-style audit ledgers. The licence moved to BSL 1.1 from version 1.9DOM.2, so check the use grant before offering it as a service.
Is immudb 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.
Does immudb support ACID transactions?
Yes. immudb supports full ACID transactions, with strong consistency.
Does immudb scale horizontally?
immudb does not scale horizontally; it runs on a single node, so you scale it up rather than out. It is comfortable at medium scale (≤ 10 TB). It supports cross-region read replicas.
How can I run immudb?
You can self-host it and embed it in your application.
What is immudb best for?
immudb is a strong fit for tamper-evident audit logs; replacing Amazon QLDB with a self-hosted ledger; and software supply-chain and compliance records. Think twice for high-churn data that must be physically deleted (e.g. GDPR erasure).
What are the best alternatives to immudb?
Common alternatives to immudb include Amazon QLDB, TigerBeetle, XTDB, Datomic and PostgreSQL. The right choice depends on your workload, scale and hosting; WhichDB's smart match ranks them against your requirements.
How popular is immudb?
immudb ranks #193 of 844 databases on the WhichDB Score (17.2/100), and #2 among ledger databases. The score combines public adoption signals such as package downloads, GitHub activity, job posts and developer discussion.