# Hugging Face Transformers v4.51.1 — Release & Upgrade Intelligence
- **Product:** Hugging Face Transformers (https://huggingface.co)
- **Version:** v4.51.1
- **Released:** Apr 08, 2025
- **Impact Score:** 5/10
- **Breaking Changes:** Not verified
- **Canonical Analysis:** https://changelogs.us/transformers/updates/v4.51.1/

## Executive Summary (TL;DR)
Hugging Face Transformers v4.51.1. Source highlight: Patch release v4.51.1

## Bug Fixes
- Fixing flex attention for torch=2.6.0 (#37285)
- more fixes for post-training llama4 (#37329)
- Remove HQQ from caching allocator warmup (#37347)
- fix derived berts _init_weights (#37341)
- Fix init empty weights without accelerate (#37337)
- Fix deepspeed with quantization (#37324)

## Upgrade Command
```bash
python -m pip install 'transformers==4.51.1'
```