nowfound

Dev tools · alternatives · 2026

24 alternatives to Fast vector similarity using Rust and Python

I recently found myself computing the similarity between lots of very high dimensional vectors (i.e., sentence embedding vectors from LLMs), and I wanted to try some more powerful measures of similarity/dependency than just Cosine similarity, which seems to be the default for everything nowadays because of its computational efficiency. There are many other more involved measures that can detect more subtle relationships, but the problem is that some of them are quite slow to compute, especially if you're trying to do it in Python. For my favorite measure of statistical dependency,…

Fast Vector Similarity is a library that computes similarity and statistical dependency measures between high-dimensional vectors using Rust and Python. It offers alternatives to cosine similarity, including measures… Below are 24 products that do a similar job, ranked by how close each is in meaning and then by launch-day votes. Fast vector similarity using Rust and Python launched in 2023; newer entries below may have overtaken it.

  1. 1

    HNSW implementation in Rust. Reference: https://arxiv.org/ftp/arxiv/papers/1603/1603.09320.pdf - swapneel/hnsw-rust

    2024 · github.com · its alternatives →

  2. 2

    All-pair set similarity search on millions of sets in Python and on a laptop - GitHub - ekzhu/SetSimilaritySearch: All-pair set similarity search on millions of sets in Python and on a laptop

    2018 · github.com · its alternatives →

  3. 3IM

    As a grad student (and an ADHDer), I had trouble doing literature review systematically. To combat this, I made a website that finds similar papers using the meaning of the thing I am looking for. I used MixedBread's [^1] embedding model to generate vectors from the abstracts. I store and search similar vectors using Milvus [^2] and finally use Gradio [^3] to serve the frontend. I update the vector database weekly by pulling the metadata dataset from Kaggle [^4]. To speed up the search process on my free oracle instance, I binarise the embeddings and use Hamming distance as a metric. I would…

    2024 · papermatch.mitanshu.tech · its alternatives →

  4. 4

    A high-performance observability data pipeline. Contribute to vectordotdev/vector development by creating an account on GitHub.

    2019 · github.com · its alternatives →

  5. 5

    Here's a small demonstration of the fundamental aspects of the word-to-vec algorithm. It's implemented in a single python script and depends only on a single text file for training. It's not meant to be blazingly fast or anything, just a toy example to aid my understanding of how word vectors might be learnt from a corpus.

    2023 · github.com · its alternatives →

  6. 6

    Hey HN, we want to share HelixDB (https://github.com/HelixDB/helix-db/), a project a college friend and I are working on. It’s a new database that natively intertwines graph and vector types, without sacrificing performance. It’s written in Rust and our initial focus is on supporting RAG. Here’s a video runthrough: https://screen.studio/share/szgQu3yq. Why a hybrid? Vector databases are useful for similarity queries, while graph databases are useful for relationship queries. Each stores data in a way that’s best for its main type of query (e.g.…

    2025 · github.com · its alternatives →

  7. 7

    I built a Rust-powered Wavelet Matrix library for Python. There were surprisingly few practical Wavelet Matrix implementations available for Python, so I implemented one with a focus on performance, usability, and typed APIs. It supports fast rank/select, top-k, quantile, range queries, and even dynamic updates. Feedback welcome!

    Dec 2025 · pypi.org · its alternatives →

  8. 8

    OctaneDB is an open-source vector database for Python that focuses on ultra-fast similarity search for high-dimensional data—perfect for AI/ML, semantic search, and large-scale document or embedding retrieval. What does it do? Store, index, and search millions of embeddings (text, images, etc.) with sub-millisecond query time. Supports in-memory and efficient HDF5 persistent storage. Integrates seamlessly with sentence-transformers for automatic text embedding. Key Features: 10x faster than Pinecone or ChromaDB for vector search and batch insertions. Advanced indexing: HNSW (approximate…

    2025 · github.com · its alternatives →

  9. 9MA

    2017 · lmcinnes.github.io · its alternatives →

  10. 10

    Hey HN! We’ve just open-sourced model2vec-rs, a Rust crate for loading and running Model2Vec static embedding models with zero Python dependency. This allows you to embed text at (very) high throughput; for example, in a Rust-based microservice or CLI tool. This can be used for semantic search, retrieval, RAG, or any other text embedding usecase. Main Features: - Rust-native inference: Load any Model2Vec model from Hugging Face or your local path with StaticModel::from_pretrained(...). - Tiny footprint: The crate itself is only ~1.7 mb, with embedding models between 7 and 30 mb. Performance:…

    2025 · github.com · its alternatives →

  11. 11AG

    This is a vector index I built that supports insertion and k-nearest neighbors (k-NN) querying, optimized for GPUs. It operates entirely in CUDA and can process queries on half a billion vectors in under 200 milliseconds. The codebase is structured as a standalone library with an HTTP API for remote access. It’s intended for high-performance search tasks—think similarity search, AI model retrieval, or reinforcement learning replay buffers. The codebase is located at https://github.com/rodlaf/BinaryGPUIndex.

    2025 · rlafuente.com · its alternatives →

  12. 12

    A Python library for detecting patterns and anomalies in massive datasets using the Matrix Profile - target/matrixprofile-ts

    2019 · github.com · its alternatives →

  13. 13

    I've been playing with embeddings and wanted to try out what results the embedding layer will produce based on just word-by-word input and addition / subtraction, beyond what many videos / papers mention (like the obvious king-man+woman=queen). So I built something that doesn't just give the first answer, but ranks the matches based on distance / cosine symmetry. I polished it a bit so that others can try it out, too. For now, I only have nouns (and some proper nouns) in the dataset, and pick the most common interpretation among the homographs. Also, it's case sensitive.

    2025 · calc.datova.ai · its alternatives →

  14. 14

    Hey HN! We are building Epsilla (https://github.com/epsilla-cloud/vectordb), an open-source, self-hostable vector database for semantic similarity search that specializes in low query latency. When do we need a vector database? For example, GPT-3.5 has a 16k context window limit. If we want to let it answer a question about a 300 page book, we cannot put the whole book content into the context. We have to choose the sections of the book that are most relevant to the question. Vector database is specialized at ranking and picking the most relevant content from a large pool…

    2023 · github.com · its alternatives →

  15. 15

    In an effort to understand it, I put together a simple, pure python implementation of HNSW, an approximate nearest neighbor library. Learned a lot, and I think for anyone interested in vector search it's an exercise that's absolutely worth doing. The code is optimized (imo) for readability, and working (albeit, quite slowly) on putting together a tutorial that walks through the motivation and implementation of HNSW. There's also working code examples for using the library for text and image search with sentence transformers and CLIP!

    2025 · github.com · its alternatives →

  16. 16

    A container for dataclasses with multi-indexing and bulk operations. - joshlk/dataclassframe

    2020 · github.com · its alternatives →

  17. 17

    Python library for embedding large graphs in 2D space, using force-directed layouts. - H4kor/graph-force

    2022 · github.com · its alternatives →

  18. 18

    We’ve just open-sourced Vicinity, a lightweight approximate nearest neighbors (ANN) search package that allows for fast experimentation and comparison of a larger number of well known algorithms. Main features: - Lightweight: the base package only uses Numpy - Unified interface: use any of the supported algorithms and backends with a single interface: HNSW, Annoy, FAISS, and many more algorithms and libraries are supported - Easy evaluation: evaluate the performance of your backend with a simple function to measure queries per second vs recall - Serialization: save and load your index for…

    2024 · github.com · its alternatives →

  19. 19

    Scalable, Low-latency and Hybrid-enabled Vector Search in Postgres. Revolutionize Vector Search, not Database. - tensorchord/pgvecto.rs

    2023 · github.com · its alternatives →

  20. 20

    A web-based application for quick, scalable, and automated hyperparameter tuning and stacked ensembling in Python. - reiinakano/xcessiv

    2017 · github.com · its alternatives →

  21. 21

    Robyn is a high-performance async Python web framework powered by a Rust runtime. Build fast, scalable web applications with Python's simplicity and Rust's speed.

    2025 · robyn.tech · its alternatives →

  22. 22IM

    Click an image to get similar images. I crawled Tumblr and used SigLIP to get vector embeddings for many images. When you click an image, it finds the most similar vector embeddings in the database, and returns the corresponding images.

    2024 · mood-amber.vercel.app · its alternatives →

  23. 23

    Heirarchical Navigable Small Worlds. Contribute to dicroce/hnsw development by creating an account on GitHub.

    2025 · github.com · its alternatives →

  24. 24

    Robyn is a Super Fast Async Python Web Framework with a Rust runtime. - sparckles/Robyn

    2023 · github.com · its alternatives →

Also compare

Ranked by how close each launch is in meaning, then by votes. Prices were read from each product’s own site when checked and can change. Refine with your own description →