Milvus

Milvus is a distributed, cloud-native vector database: storage and compute are separated, indexes support multiple algorithms (HNSW, IVF, DiskANN, GPU-accelerated indexes), and it's designed to scale to billions of vectors across a cluster rather than run as a single embedded process. Version 3.0, released 2026-07-29, adds 'lake-native' access — it can build indexes directly over data already sitting in Iceberg, Lance, Parquet or Vortex format in object storage, instead of requiring a separate ingest/copy step. That's a real architectural move, not just a version bump: the trade press covering it (Blocks & Files) notes Milvus's vector-database competitors — Pinecone, Qdrant, Weaviate — are making similar lake-integration moves, so this closes a gap rather than opening a unique one.

The GitHub repo is Apache 2.0 with no source-available or field-of-use restriction, so self-hosting costs nothing beyond your own infrastructure. The company behind it, Zilliz, sells a separate managed service (Zilliz Cloud) with a real free tier (5 GB storage, 2.5M vCUs/month, up to 5 collections, no card required) and published usage pricing beyond that. Running Milvus yourself means operating etcd, object storage (MinIO/S3), Pulsar/Kafka and the Milvus components yourself — it is not a single binary, and that operational surface is the trade-off for zero licence cost.

Verified directly from the live pricing calculator on 2026-08-20. Free tier: $0/month, 5 GB storage, 2.5M vCUs/month included. Standard tier: Serverless from $0/month pay-as-you-go, or Dedicated from $126/GB/month. Enterprise tier (marked 'most popular'): Dedicated from $197/month, adds a 99.95% uptime SLA, SSO (SAML), RBAC, private endpoints/VPC peering. Business Critical (HIPAA-eligible, CMEK, global cluster/DR) and BYOC are quote-only. Dedicated clusters are billed per Compute Unit (CU) by cluster type: Performance-optimized from $63, Capacity-optimized from $16, Tiered-storage from $5, all per million 768-dim vectors/month. The calculator's own worked example — 1 Capacity-optimized Query CU plus 4.05 GB storage — comes to $126.10/month, and new accounts get $200 in free credits to test real costs before committing.

Very active: 45,700 GitHub stars, 4,186 forks, 369 contributors, and pull requests were merged the same day this was checked (2026-08-20), with the repo pushed to hours earlier. Milvus graduated from incubation to full graduated-project status in the LF AI & Data Foundation in June 2021 — it was contributed by Zilliz in January 2020 but is now under multi-vendor open governance rather than sitting solely under one company's repo, which is a real difference from OSS projects where the founding company keeps unilateral control. pymilvus (the Python client) shipped its latest release, 3.0.1, on 2026-07-29.

GitHub's advisory database lists two critical-severity vulnerabilities disclosed for Milvus in the trailing twelve months. CVE-2025-64513 (published 2025-11-10, patched in 2.4.24/2.5.21/2.6.5): a critical authentication-bypass in the Milvus Proxy. CVE-2026-26190 (published 2026-02-11, patched in 2.5.27/2.6.10): the metrics port (9091) exposed the full REST API with no authentication by default, plus a debug endpoint with a predictable, hardcoded default auth token, together allowing unauthenticated data manipulation and credential-hash disclosure. Both are fixed in versions well before the current v3.0.0 (2026-07-29), so a current install pulling the latest release is not exposed to either. The pattern worth noting for a self-hoster: both issues were about a management/metrics port being reachable and under-authenticated by default, not about the core search path — standard practice is to keep that port off any public network regardless of patch level.

Zilliz, the company that created and primarily maintains Milvus and sells the managed Zilliz Cloud service, has raised a total of about $113M according to its own newsroom, with the most recent disclosed round being a $60M Series B extension in August 2022 led by Prosperity7 Ventures. No later funding round surfaced in a search as of 2026-08-20 — that's four years without a disclosed raise in a category (vector databases / AI infrastructure) that has seen heavy investment since. That could mean the company reached profitability or simply hasn't needed to raise publicly; either way, it's not established from public sources, so treat the absence as a gap in the record rather than a signal in either direction.

G2's Milvus review page returned an HTTP 403 to every fetch method tried (direct, proxy, and a real browser), so no independent rating or review count could be verified. Not established — this is a gap in available evidence, not a finding about the product.