# Sentence Transformers is joining Hugging Face!

[Hugging Face](https://yomu.fyi/company/hugging-face) · Tom Aarsen · Oct 22, 2025

**Type:** Announcement

## Summary

Sentence Transformers is officially transitioning its stewardship from the Ubiquitous Knowledge Processing Lab at TU Darmstadt to Hugging Face. The open-source embedding library was introduced in 2019 by Nils Reimers using a Siamese network architecture to overcome standard BERT limitations on sentence-level semantics. Tom Aarsen of Hugging Face has maintained the project since late 2023 and will continue leading its development. Under Hugging Face, the project retains its Apache 2.0 license and leverages infrastructure such as continuous integration and automated testing. Sentence Transformers currently serves over one million monthly unique users, with more than 16,000 community models publicly hosted on the Hugging Face Hub.

## Context

Sentence Transformers was developed at TU Darmstadt's UKP Lab to address limitations in standard BERT embeddings for sentence-level semantic tasks, eventually growing to over 16,000 public models and one million monthly active users.

## Approach / What changed

Hugging Face is taking over full stewardship and hosting for the project, maintaining its Apache 2.0 open-source license while leveraging Hugging Face continuous integration, testing infrastructure, and community ecosystem.

## Takeaways

- Sentence Transformers is moving from TU Darmstadt's UKP Lab to Hugging Face under project lead Tom Aarsen.
- The library continues to be open source and licensed under the Apache 2.0 license.
- The project has grown to host over 16,000 models on the Hugging Face Hub and serves more than one million monthly unique users.

**Tags:** [LLMs](https://yomu.fyi/topic/llm), [Machine Learning](https://yomu.fyi/topic/machine-learning), [Open Source](https://yomu.fyi/topic/open-source), [Search](https://yomu.fyi/topic/search)

[Read original post](https://huggingface.co/blog/sentence-transformers-joins-hf)