ExFastembed

ExFastembed is an Elixir wrapper around the fastembed-rs crate. It provides a simple interface to load various text embedding models and reranker models, generate embeddings for a list of texts, and rerank documents based on a query.

Installation

Add ex_fastembed to your list of dependencies in mix.exs:

def deps do
  [
    {:ex_fastembed, github: "elchemista/ex_fastembed", branch: "master"}
  ]
end

How to compile:

• Install clang (e.g., sudo apt install clang)
• Install Rust (e.g., curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh)

export CC=/usr/bin/clang CXX=/usr/bin/clang++ RUSTLER_PRECOMPILATION_EXAMPLE_BUILD=1 && mix compile

Usage

Loading an Embedding Model

Before generating embeddings, you must load one of the supported text embedding models. For example, to load the BAAI/bge-small-en-v1.5 model:

iex> ExFastembed.load("BAAI/bge-small-en-v1.5")
#It returns either:
# {:ok, dimension } when the model is successfully loaded, or
# {:error, "Model already loaded!" } if it has been loaded previously.

Generating Embeddings

After loading the embedding model, you can generate embeddings for a list of texts:

iex> ExFastembed.embed_text(["Hello, world!", "Elixir is awesome"])
#Expected output:
# {:ok, [[...], [...]] }

Loading a Reranker Model

To load a reranker model, use the load_reranker/1 function. For example, to load jinaai/jina-reranker-v1-turbo-en:

iex> ExFastembed.load_reranker("jinaai/jina-reranker-v1-turbo-en")
#It returns either:
# {:ok, true } when the model is successfully loaded, or
# {:error, "Reranker already loaded!" } if it has been loaded previously.

Reranking Documents

Once the reranker model is loaded, you can rerank documents based on a query:

iex> ExFastembed.rerank("search query", ["Document 1", "Document 2"], true)
#Expected output:
# {:ok, [{0, 0.95, "Document 1" }, {1, 0.90, "Document 2" }] }

Supported Models

Embedding Models

• "BAAI/bge-small-en-v1.5"
• "sentence-transformers/all-MiniLM-L6-v2"
• "sentence-transformers/all-MiniLM-L12-v2"
• "mixedbread-ai/mxbai-embed-large-v1"
• "Qdrant/clip-ViT-B-32-text"
• "BAAI/bge-large-en-v1.5"
• "BAAI/bge-small-zh-v1.5"
• "BAAI/bge-base-en-v1.5"
• "sentence-transformers/paraphrase-MiniLM-L12-v2"
• "sentence-transformers/paraphrase-multilingual-mpnet-base-v2"
• "lightonai/ModernBERT-embed-large"
• "nomic-ai/nomic-embed-text-v1"
• "nomic-ai/nomic-embed-text-v1.5"
• "intfloat/multilingual-e5-small"
• "intfloat/multilingual-e5-base"
• "intfloat/multilingual-e5-large"
• "Alibaba-NLP/gte-base-en-v1.5"
• "Alibaba-NLP/gte-large-en-v1.5"

Reranker Models

• "BAAI/bge-reranker-base"
• "BAAI/bge-reranker-v2-m3"
• "jinaai/jina-reranker-v1-turbo-en"
• "jinaai/jina-reranker-v2-base-multiligual"

License

ExFastembed is released under the Apache License 2.0. See LICENSE for details.

Acknowledgments

ExFastembed is a wrapper around fastembed-rs, a fast Rust-based text embedding library.