# vLLM v0.20.1 — Release & Upgrade Intelligence
- **Product:** vLLM (https://vllm.ai)
- **Version:** v0.20.1
- **Released:** May 04, 2026
- **Impact Score:** 5/10
- **Breaking Changes:** Not verified
- **Canonical Analysis:** https://changelogs.us/vllm/updates/v0.20.1/

## Executive Summary (TL;DR)
vLLM v0.20.1. Source highlight: This is a patch release on top of `v0.20.0` primarily focused on **DeepSeek V4 stabilization and performance improvements**, along with several important bug fixes.

## Bug Fixes
- Fixed persistent topk cooperative deadlock at TopK=1024 (#41189) and inter-CTA init race on RadixRowState (#41444), with temporary disable of persistent topk as a workaround (#41442).
- Fixed import error due to AOT compile cache loading (#41090).
- Fixed torch inductor error (#41135).
- Fixed repeated RoPE cache initialization (#41148).
- Fixed missing type conversion for non-streaming tool calls in DSV3.2/V4 (#41198).
- Fixed `max_num_batched_token` not being captured in CUDA graph (#40734).

## Upgrade Command
```bash
python -m pip install 'vllm==0.20.1'
```