Antfly vs pgvector
Open-source vector similarity search for PostgreSQL
Feature Comparison
| Feature |  Antfly | pgvector |
|---|---|---|
| Price | ||
| Price | $ Open source, self-hosted | $ Free extension; PostgreSQL hosting varies |
| Search | ||
| Vector Search | Native Built-in vector engine with hybrid search | Native IVFFlat and HNSW indexes for vector similarity |
| Full-Text Search | Native BM25 + semantic hybrid search | Native PostgreSQL built-in tsvector/tsquery |
| Hybrid Search | Native Unified BM25 + vector scoring in a single query | Partial Requires custom SQL combining tsvector + vector queries |
| Inference Models | ||
| Model Execution | Native Antfly Inference runs embedders, rerankers, chunkers locally | None No model execution; requires external APIs |
| Re-ranking | Native Built-in cross-encoder reranking via Antfly Inference | None No native reranking |
| End-to-End RAG | Native Ingest, embed, store, retrieve, rerank, generate | None Requires 4-5 external services for a full pipeline |
| Modalities | ||
| Text | Native Built-in text embeddings via Antfly Inference | Partial Stores text vectors; requires external embedding |
| Image | Native CLIP image embeddings via Antfly Inference | None No native image support |
| Audio | Native Audio embeddings via Antfly Inference | None No native audio support |
| Video | Native Video frame embeddings via Antfly Inference | None No native video support |
Native PDF chunking and embedding via Antfly Inference | None No native PDF support | |
| Storage | ||
| Structured Data / ACID | Native Full document store with ACID transactions | Native Best-in-class relational database with full ACID |
| Distributed Consensus | Native Multi-Raft consensus with automatic sharding | Partial Relies on Citus or manual partitioning for distribution |
| Multi-Tenancy | Native Namespace-level tenant isolation | Partial Schema or row-level security based |
| Hosting | ||
| Self-Hosted | Native Run anywhere: single binary or Kubernetes | Native Self-hosted anywhere PostgreSQL runs |
| Cloud-Hosted | Partial Cloud offering coming soon | Native Available on RDS, Supabase, Neon, and others |
| Operations | ||
| Operational Simplicity | Native Single binary, zero-config standalone mode | Partial Standard PostgreSQL administration applies |
Why Antfly
- Antfly runs on top of Postgres, not instead of it: built-in CDC replication streams your tables into the retrieval layer
- Built-in ML inference eliminates external embedding API costs
- Hybrid BM25 + vector retrieval with reranking and pruning, no hand-rolled SQL
- pgvector stores and matches vectors; Antfly adds the judgment layer: ranking, pruning, and learning from use
- Keep Postgres as your system of record; add the retrieval agents need
Pricing
Antfly
Open source, self-hosted. Cloud pricing TBD.
pgvector
Free extension. PostgreSQL hosting varies; RDS from ~$30/mo, Supabase from $25/mo.
pgvector itself is free; the external embedding, reranking, and orchestration services around it are the cost that adds up.
Deep Dive
pgvector brings vector similarity search to PostgreSQL, and if your team runs Postgres, you should probably have it. It keeps vectors next to your data, costs nothing to install, and is well maintained.
The question isn't pgvector or Antfly, because they sit at different layers. Postgres is your system of record, and pgvector gives it vector storage and similarity matching. What it doesn't give you is the rest of retrieval: embedding generation, hybrid fusion, cross-encoder reranking, score-based pruning, and multimodal indexing still come from external services and hand-crafted SQL.
Antfly sits on top of Postgres rather than replacing it. Built-in CDC replication streams your tables into a retrieval layer that adds hybrid BM25 + vector ranking, local ML inference, reranking, and pruning, and gets sharper with use. Keep your Postgres. Add retrieval. See the PostgreSQL Replication guide for the setup.