Better Auth Joins Vercel

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Better Auth is joining Vercel

Better Auth, the open source auth framework, is joining Vercel. The goal is to give the team more support to keep building auth in the open while staying framework-agnostic. The post also shares the story behind Better Auth, from solving multi-tenant auth problems in Next.js to later taking over Auth.js / NextAuth.js. Looking ahead, the team wants to invest more in auth for AI agents, where apps need secure and revocable access on behalf of users.

From Vercel Ship

• Run any Dockerfile on Vercel
• Turbopack: What's New in Next.js 16.3
• Introducing VCR: Vercel Container Registry
• Vercel Sandbox now supports FUSE-based filesystems
• Vercel Functions can now be up to 5GB in package size

⚡️ Sponsor: Blazity

Next.js migration toolkit that eliminates guesswork and protects production and stability. Most Next.js migrations from Pages Router to App Router follow the same pattern: a developer reads the docs, starts converting files, breaks something in production, then spends weeks firefighting. The real problem with migrations are the edge cases nobody warns you about, and the lack of systematic approach. We’ve done enough migrations to confidently say - we’ve been there and done that. So we built Skills.md - an agent-oriented migration toolkit that gives AI coding agents (and developers) a structured, production-safe path from Pages Router to App Router. Instead of guesswork and broken deploys you get a repeatable process built from real migration experience. It's open source and built for Skills.sh.

📙 Articles / Tutorials / News

Different hydration and rendering strategies

Covers CSR, SSR, streaming, islands, React Server Components, and more, with the pros and cons of each.

RFC: WebSocket Upgrades in Route Handlers

A new draft proposal from the Next.js team wants to bring built-in WebSocket support to App Router Route Handlers.

reactperf

40 steps across 11 sections covering the main parts of React performance. This guide explains common slowdowns like extra re-renders, effect problems, large lists, bundle size issues, and layout work, all in a simple order that builds from one topic to the next.

📦 Projects / Packages / Tools

AI SDK 7

New features include better reasoning controls, tool and runtime context, file and skill uploads, MCP Apps, a terminal UI, tool approvals, durable workflows, and timeout support.

Astryx

Meta has open sourced the design system. It includes 150+ accessible React components, brand-level theming, dark mode, ready-to-ship templates, and a CLI, all without forcing you into a styling setup. It uses StyleX under the hood.

react-stinky

If your React components are getting messy, this tool aims to help. It checks for common code smells across a whole component or file, including bad state flow, weak accessibility, hook mistakes, and TypeScript issues.

Unlayer Elements

A new open source React component library that lets teams create transactional emails, landing pages, and documents from the same component model.

⚡️ Sponsor: Expo

How is your app performing in production? Most teams learn about performance regressions from user complaints. Observe surfaces them within hours of the release that caused it.

🌈 Related

React Compiler Is A Retrofit

This article argues that React Compiler is useful, but it is still a workaround for React’s long-standing identity and memoization issues.

Writing Custom Renderers for React

With React Test Renderer now deprecated, Maciej Jastrzębski explains how and why he built a new test renderer for React Native Testing Library. It’s a useful look at what React renderers actually do, how the reconciler works, and how React turns components into platform-specific UI.

Why Drizzle ORM couldn't publish new releases on NPM for a month

Drizzle ORM recently hit a little-known npm limit that blocks publishing once a package’s full metadata file grows beyond 100 MB. The article explains why this happens, how older versions add up over time, and why publishing lots of dev or snapshot builds is usually a bad idea.