Helion is an open-source graph and vector database written in Rust. It combines graph traversal, dense and sparse vector search, Qdrant-compatible HTTP APIs, and disk-backed storage in one self-hosted engine.
Helion is maintained by Context Engine AI and distributed under
GPL-3.0-only. Compatibility-sensitive crate names and runtime paths still use
helix and helixdb.
Context Engine started with two databases: Qdrant for vector search and Memgraph for graph relationships. That combination helped us get the product off the ground, but it also meant operating two storage systems, two scaling models, two backup paths, and an application layer responsible for joining the answers.
By April 2026, our startup runway was shrinking. We could no longer afford the financial and operational cost of running both databases, yet graph and vector retrieval were both fundamental to the product. We needed one engine that we could understand, operate, and improve ourselves.
HelixDB already brought graph and vector primitives together in Rust. We began
from its last unambiguous GPLv3 source point, commit
71ebdb9,
and built an independent line around the constraints we actually had: local
disk, object storage, bounded memory, compatibility with existing clients, and
the ability to debug every layer when production went wrong. We did not copy
source from the later AGPL line; the detailed boundary is recorded in
PROVENANCE.md.
HelixDB has since moved its current project to Apache-2.0. We appreciate that decision and the upstream team's renewed investment in permissive open source. Helion remains a separate GPLv3 project because that is the lineage from which our work began and the license under which we are releasing our combined work.
Helion is what came out of that moment: not a theoretical database rewrite, but a startup learning to own its infrastructure because it had to.
- Dense HNSW and sparse-vector search with payload filtering
- Native graph storage and traversal APIs
- Qdrant-compatible collection, point, search, scroll, facet, and snapshot routes
- LMDB storage with WAL, snapshots, and automatic map growth
- Optional SlateDB-backed LSM storage on S3-compatible object storage
- Single-writer fencing and read-replica support for the LSM backend
- HelixQL compiler and local CLI workflow
- Raft-capable replication primitives
docker build -t helion-db .
docker run --rm \
-p 6969:6969 \
-v helion-data:/data \
helion-dbThe service listens on http://localhost:6969. Check it with:
curl http://localhost:6969/healthRequirements:
- Rust 1.94 or later
clang,pkg-config, OpenSSL development headers, and Protocol Buffers
cargo build --release -p helix-container
HELIX_DATA_DIR=/tmp/helion-data \
./target/release/helix-containercargo install --path helix-cli
helix init --path ./example-project
helix check --path ./example-project
helix deploy --path ./example-project --localHelion supports two storage modes selected through HELIX_STORAGE_BACKEND:
lmdb: local disk-backed storage and the default for a single-node deploymentlsm: SlateDB-backed storage using S3 or an S3-compatible object store
Local LSM examples are available under deploy/lsm-cloud/ for Docker Compose,
MinIO, and Minikube. Kubernetes tuning examples are configuration templates,
not credentials or production manifests.
helixdb: graph/vector engine, query compiler, storage, and protocol typeshelix-container: HTTP server binaryhelix-cli: local project and deployment CLIhbuild: build helperget_routes: handler-registration proc macrovendor/slatedb: vendored Apache-2.0 SlateDB fork with separate provenance
The public project is named Helion and its repository is
Context-Engine-AI/helion-db. Existing helix, helixdb, and
.helix/repo/helix-db identifiers remain where changing them would break CLI,
crate, query, or storage compatibility.
See CONTRIBUTING.md. By contributing, you agree to license
your contribution under GPL-3.0-only.
Helion is built and maintained at Context Engine AI by:
Helion is licensed under the GNU General Public License version 3 only. See LICENSE, COPYRIGHT, and PROVENANCE.md.