One binary handles dense, sparse, tensor, and full-text search
Infinity gives RAG apps a single C++ backend for hybrid search across dense vectors, sparse vectors, tensors, and full-text, aiming to replace the usual patchwork of specialized engines.

What it does
Infinity is a C++20 database that stores and queries structured data alongside dense vectors, sparse vectors, tensors, and full-text. It targets retrieval-augmented generation and other LLM workloads by offering a unified search backend instead of forcing developers to wire up separate vector and text engines. The project ships as one self-contained binary with no external dependencies and exposes a Python API.
The interesting bit
The “hybrid search” pitch is common, but Infinity also treats tensors—multi-vector representations like ColBERT embeddings—as a first-class data type with native reranking support. That suggests it is trying to absorb newer retrieval models, not just classic k-NN and BM25.
Key highlights
- Self-reported latency of 0.1 ms and 15K+ QPS on million-scale vector datasets, and 1 ms with 12K+ QPS on 33M-document full-text corpora.
- Supports hybrid queries across all four search types—dense, sparse, tensor, and full-text—with built-in filtering and rerankers including
RRF, weighted sum, andColBERT. - Runs as a standalone server or embedded directly in Python; the server is a single dependency-free binary.
- Requires
x86_64withAVX2; compatible with Linux, macOS, or Windows via WSL2.
Verdict
Teams building RAG pipelines who are tired of gluing together a vector database, a sparse retrieval engine, and a text search index should evaluate this. If you only need simple vector similarity or already run a heavily customized search stack, it may be overkill.
Frequently asked
- What is infiniflow/infinity?
- Infinity gives RAG apps a single C++ backend for hybrid search across dense vectors, sparse vectors, tensors, and full-text, aiming to replace the usual patchwork of specialized engines.
- Is infinity open source?
- Yes — infiniflow/infinity is open source, released under the Apache-2.0 license.
- What language is infinity written in?
- infiniflow/infinity is primarily written in C++.
- How popular is infinity?
- infiniflow/infinity has 4.6k stars on GitHub.
- Where can I find infinity?
- infiniflow/infinity is on GitHub at https://github.com/infiniflow/infinity.