#96: Better Upload, Building Vercel Fluid, AI SDK5, Leaving TanStack for Next.js, Puppeteer on Vercel, Useless useCallback

Fluid: How we built serverless servers – Vercel dropped the engineering details behind Fluid Compute and Active CPU pricing. By building a custom transport layer, they enabled streaming and can now send multiple requests to the same Lambda instance

We’ve moved from TanStack Start to Next.js – Switching from TanStack Start to Next.js led to better performance and SEO. Lighthouse scores increased, and the site now loads faster. CPU and memory usage are more consistent. Next.js also simplified the development process. Check out 𝕏 Tanner’s response to this post

𝕏 Next.js Conf 2025 - Call for proposals – Apply to give a 20-minute, in-person talk in San Francisco about your journey with Next.js

Vemetric - Simple, yet actionable Web & Product Analytics – Vemetric is open-source and privacy-first. It helps you to understand the complete user journey from first visit to feature adoption.

Instrumenting Next.js with runtime secret injection – Use the instrumentation file in Next.js to fetch and inject secrets, such as environment variables, into your app at runtime

Stop Shipping Bloat: Practical Bundle Diet for Next.js Developers – Lists methods for making Next.js applications faster by shrinking their JavaScript bundles

Deploying Puppeteer with Next.js on Vercel – Covers the required configuration steps to build and deploy a screenshot generator on Vercel

[Experiment] <Link unstable_dynamicOnHover> – This feature was added a while back. It’s like prefetch={true}, but triggered by your mouse

Better Upload – File uploads made easy! The package handles client and server code, supports multipart uploads, and works with any S3-compatible storage. It also provides ready-made shadcn/ui components

AI SDK 5 – This is a huge update. The redesigned chat is now fully type-safe from server to client, with a clean split between UI and model messages. You get agentic loop control for building reliable AI agents, customizable message types, streaming typed data parts, and tool invocations that are actually type-safe. There is much more. Definitely worth checking out!

TanStack DB – TanStack DB is a new client-side database for TanStack Query. It keeps data in memory and updates only what has changed. You can use it with your current useQuery calls, and it works with REST, GraphQL, or real-time sync engines

EvilCharts – A modern, customizable chart library for React and Next.js applications featuring visually stunning and interactive data visualizations

Escape the vendor-locked in edge-runtime! Try Sevalla with $50 credit now. Your PaaS from the future – Prefer the power of a full Node.js environment? Get lower bandwidth costs and predictable pricing combined with real human support by developers. No seats, no surprise serverless bills. Ever.

The Useless useCallback – The article calls out the overuse of memoization in React, especially when it does… absolutely nothing and explains why patterns like the “latest ref” (or the upcoming useEffectEvent) are often a better fit

Writing Code Was Never The Bottleneck – The speed of writing code has improved with LLMs, but the main obstacles are still reviewing, testing, and sharing knowledge. These steps take time and effort, and LLMs do not solve these core issues.

It’s time for modern CSS to kill the SPA – Native CSS transitions have quietly killed the strongest argument for client-side routing. Yet people keep building terrible apps instead of performant websites.

How Parcel bundles React Server Components – Parcel now supports React Server Components. This article explains how Parcel handles code splitting, module environments, and the "use client" directive