helix-db vs hydradb
Rust OLTP graph database on object storage with native vector and BM25 search: property graph, traversal-prefiltered ANN and full-text in one transactional engine; Rust, TS, Go, Python SDKs. — versus — Object-store-native distributed graph DB in Rust: graph on SlateDB over S3, snapshot-consistent OpenCypher, GraphBLAS traversal, Neo4j Bolt 5.x compatibility, disaggregated data nodes and indexers.
Both are Rust graph databases built on object storage. hydradb speaks OpenCypher and Neo4j Bolt for drop-in compatibility; HelixDB fuses vector and BM25 search into the graph engine for agent retrieval.
| helix-db | hydradb | |
|---|---|---|
| Stars | 6.1k | 12k |
| Forks | 371 | 5.1k |
| Language | Rust | Rust |
| License | Apache-2.0 | AGPL-3.0 |
| Last activity | today | 1 months ago |
| Topics | knowledge-graphs, rag | knowledge-graphs, storage |
| Curated connections | 3 | 5 |
helix-db — the curator's take
Pick HelixDB when your agent's retrieval is really a graph question with a similarity step inside it ('passages near this embedding, but only ones linked to this customer') and you would rather not glue Neo4j to a vector store and keep them consistent. Graph, vectors and BM25 live in one transactional engine on object storage, queried through typed SDK builders in four languages, and `helix chef` scaffolds an app through your coding agent. Local dev needs Docker or Podman unless you use embedded mode. Skip it if you need Cypher or Bolt compatibility with an existing Neo4j stack (hydradb speaks both), or if your data is flat documents: a plain vector store is simpler.
hydradb — the curator's take
Consider it when you want a Neo4j-shaped graph (Cypher, Bolt drivers) but with cloud-native durability — S3 is the only copy that matters, and compute nodes are disposable and scale independently. That makes it a fit for large agent-memory or knowledge graphs on a budget where you'd rather not run a stateful Neo4j cluster. Avoid it for embedded or single-process use (latticedb, pggraph or plain SQLite are simpler), for early-stage projects that need battle-tested drivers and tooling, and note the AGPL-3.0 licence if you embed it in a product. Still 0.x; verify with a round-tripped write, as its own README insists.