NebulaGraph

https://nebula-graph.io

v5.2 adds graph-vector-text hybrid retrieval natively. MCP server for Claude/GPT agents. GraphRAG in three lines of code.

At a glance

Type
Graph + vector + text hybrid retrieval
Tier
T2
Created
2018
Latest release
not applicable — not OSS
License
not applicable — not OSS
GitHub
not applicable — no GitHub repo
Pricing
OSS (Apache-2.0) + NebulaGraph Enterprise (commercial)
Funding
$18M total (Seed + pre-A); investors: Redpoint China Ventures, Matrix Partners China, Source Code Capital, Jeneration

Taxonomy

storage
graph
retrieval
graph-traversal
persistence
long-term
update
overwrite
unit
fact
governance
inspectable
conflict
overwrite

When to use

Optimised for: relationship modeling + reasoning + governance over pure vector

Anti-fit: not for purely-vector or simple-RAG use cases (graph adds setup cost)

Pros & cons

Pros

Strong at trillion-edge scale; popular in China for fraud / social-network workloads.

Cons

Heavy operational overhead; documentation in English lags Chinese resources.

Claims & capabilities

100× faster path queries. Open-source + commercial.

Technical surface

API surface
nGQL, SDK: Python, Java, Go, JS, C++
Backend storage
custom (RocksDB-backed distributed graph)
Deployment
Both (self-hosted + NebulaGraph Cloud)
Embedding model
BYO
Multi-tenancy
namespace
MCP
no first-party MCP adapter published as of 2026-05; community connectors may exist.
A2A
no Google A2A (Agent2Agent) integration documented as of 2026-05.
OpenTelemetry
via Prometheus

Similar systems

Other knowledge-graph platforms in the catalog, ranked by inbound references.

  • Neo4j T1

    Property graph DB with Cypher; native vector search; Aura Agent + MCP server for graph-as-memory. $100M GenAI investment in 2025.

  • Amazon Neptune Analytics T1

    Vector index on graph nodes queryable via openCypher. Mem0 integration GA 2025; Cognee integration for agentic RAG. Combines semantic recall with multi-hop traversal in one managed service.

  • AllegroGraph (Franz) T1

    RDF triple/quad store with RDFS++ / OWL reasoning. v8.4 (May 2025) added an NLQ interface.

  • Apache AGE T2

    openCypher over Postgres. Pairs with pgvector for graph + vector hybrid retrieval. Azure Database for PostgreSQL ships AGE with ai_extension LLM functions for entity extraction directly in SQL.

  • ArangoDB T1

    HybridGraphRAG combines vector search, graph traversal, full-text in one AQL query. ArangoGraphML for ML pipelines; LangChain integration.

  • Dgraph T2

    Vector indexing on any node. Google Gen AI Toolbox integration; LangChain agent orchestration.

Row last verified 2026-05-14. Catalog data is CC-BY-4.0 — see how to read this.