# Tailwind CSS v4.1.7 — Release & Upgrade Intelligence
- **Product:** Tailwind CSS (https://tailwindcss.com)
- **Version:** v4.1.7
- **Released:** May 15, 2025
- **Impact Score:** 5/10
- **Breaking Changes:** Not verified
- **Canonical Analysis:** https://changelogs.us/tailwind/updates/v4.1.7/

## Executive Summary (TL;DR)
Tailwind CSS v4.1.7. Source highlight: Upgrade: Migrate bare values to named values (#18000)

## New Features
- Upgrade: Migrate bare values to named values (#18000)
- Upgrade: Added cache to improve template migration performance (#18025)

## Bug Fixes
- Allow `_` before numbers during candidate extraction (#17961)
- Prevent duplicate suggestions when using `@theme` and `@utility` together (#17675)
- Ensure that media queries within `::before` and `::after` pseudo selectors create valid CSS rules in production builds (#17979)
- Ensure that the standalone CLI does not leave temporary files behind (#17981)
- Ensure `-rotate-*` utilities properly negate arbitrary values (#18014)
- Ignore custom variants using `:merge(…)` selectors in legacy JS plugins (#18020)

## Upgrade Command
```bash
npm install --save-exact tailwindcss@4.1.7
```