TerminusDB: At a glance

This page gives you a high-level overview of TerminusDB's capabilities — what it does, how it differs from other databases, and where to go next depending on your use case.

TerminusDB is an open-source document graph database with built-in version control. It combines a schema-enforced JSON document store with a knowledge graph engine, git-like collaboration (branch, diff, merge, clone), and ACID transactions backed by an immutable storage layer.

Three things make it distinctive:

1. Documents + Graph in one — Write and read JSON documents; under the hood, data is stored as a typed graph of triples. No need to choose between document-store convenience and graph traversal power. See The Document Model.

2. Git-for-data — Branch, merge, diff, reset, and time-travel through your data history. Push and pull between instances. See Version Control.

3. Datalog query engine (WOQL) — A declarative query language based on Prolog foundations. Pattern-match across documents and relationships without JOINs, with built-in support for aggregation, path queries, and schema-aware traversal. See WOQL Explained.

TerminusDB is maintained by DFRNT® in collaboration with the open-source community.

Overview of the system

• A versatile document graph database
• flexible headless content management system

Document graph paradigm

• model-based and structured JSON records
• git-for-data
• complex content

ACID RDF graph database with history and branches

• RDF graph database with immutable history
• graph database with ACID transactions
• full immutable history
• advanced type model with inheritance
• taxonomies with both inherited fieldsets and values

RDF semantics with a Closed World Assumption (rules engine)

• collaborative semantic infrastructure
• logic reasoning on information models
• rules-engine for complex digital twin graphs

Datalog query engine

• logical reasoning
• immutable history built in
• WOQL Abstract Syntax Tree (AST)
• how to query with WOQL
• Javascript WOQL Client
• Python WOQL Client

Data model and schema management

• schema migration
• XML Datatypes for its data structures
• schema reference

Git-for-data

• git-for-data (including push, pull clone and branching)

Interoperability

• REST (OpenAPI Reference)
• WOQL datalog query language
• Rust-based high performance GraphQL Engine
• Javascript Client
• Python Client

Complete User Interface

The DFRNT Studio for TerminusDB offers a commercially packaged solution, with hosting API tokens and collaborative environments, modelling environment and document UI that help you go from idea to prototype and production in a few hours or a few days.