In my latest video, you're going to learn how to work with state and state management in React and how to combine it with the local storage for persistence.

We're going to go over all of the different ways that you can handle state in React, from the simplest use cases with local state all the way up to a proper state management solution.

Then we are going to combine that with the local storage to extend our state to persist across user sessions! This is your complete guide to everything state in React.

⚠ Common React Mistakes and How to Correct Them
React gives you predictable UIs, if you stick to its rules. But in the real world, many devs fall into traps like misusing state, abusing key for re-renders, or memoizing too early. This post breaks down 15 high-impact anti-patterns seen in day-to-day code reviews, with clear “what’s wrong” explanations and copy-pasteable solutions that’ll make your app faster and more reliable.

🔢 An Interactive Guide to TanStack DB
In this hands-on guide, Maxi Ferreira explores TanStack DB, a powerful new reactive client store built on differential dataflow and designed to bring real-time sync, live queries, and transactional mutations to frontend apps. Unlike traditional state management, it’s optimized for speed, scale, and relational data, and plays nicely with existing REST APIs or modern sync engines like ElectricSQL.

📱 How Shopify Migrated to React Native's New Architecture
In a major engineering effort, Shopify successfully migrated its mobile and POS apps, used by millions, to React Native’s New Architecture, all while maintaining weekly releases and performance parity. The blog breaks down their migration strategy, technical challenges, and rollout approach, offering a valuable read for teams tackling similar transitions at scale.

🦸 The Ultimate UI Kit for React + Tailwind CSS
HeroUI is a modern, accessible React UI library built on Tailwind CSS, letting developers quickly design responsive apps with 210+ customizable components, full dark mode, and theme support out of the box. With built-in accessibility, zero runtime styles, and full TypeScript support, it’s built for performance and scale.

Quick Links

🐛 Largest NPM Compromise in History
On September 8, Aikido's intel feed flagged malicious code in 18 major npm packages, including chalk, debug, and strip-ansi, collectively over 2 billion weekly downloads. The attack silently hijacked crypto and Web3 activity in users' browsers, redirecting funds to attacker wallets. The threat has since been mitigated, but the scope and stealth of this compromise mark one of the largest npm attacks to date.

📖 Writing Code Is Easy. Reading It Isn’t
In this post, Ibrahim Diallo explores why reading code is far harder than writing it, pointing to the mental overhead of building a model of unfamiliar systems. He argues that understanding, not generating, is the real bottleneck in software development, especially in the age of LLMs. Until machines can help us understand code, not just spit it out, the hard part remains.

🧠 Claude can now create and edit files
Claude just leveled up: it can now create and edit Excel files, Word docs, PDFs, and slide decks directly from chat instructions. This feature, now in preview for Max, Team, and Enterprise plans, turns Claude into a hands-on project assistant, transforming data into polished outputs like charts, models, and formatted reports in minutes. Pro plan access is coming soon.

💻 Google Chrome at 17 - A history of our browser
This blog post by Addy Osmani walks through Chrome’s 17-year evolution, covering its origin story, performance breakthroughs, security architecture, and new AI-powered features like Gemini tab organizers and DevTools assistants. From its 2008 debut with a comic book launch to breaking Speedometer records and enabling local LLMs in the browser, Chrome’s journey is a deep dive into how the team has chased speed, security, simplicity, and stability, and what’s next.

😠 I love UUID, I hate UUID
At Epsio, efficient deletes in stream processing led the team to embrace UUIDs as primary keys. But while UUIDv4s offer global uniqueness, they crush database performance due to poor index locality. The fix? UUIDv7, timestamp-infused, sequentially-sortable, and 31% faster on inserts with 22% smaller index sizes. Just don’t expose those timestamps publicly.

Soon I’ll be opening up Cosden Code, a new kind of React learning platform where expert-designed content meets AI-powered, interactive guidance.
It’s built to help you go deep, stay focused, and actually retain what you learn.

P.S. If you’re on the waitlist: things are moving fast. The core of the platform is coming together, and I’m excited about how it’s all shaping up. More updates (and a few sneak peeks) coming your way soon.

If you’re not on the waitlist, you can join here!