Rodrigo Castilho

Staff Frontend Engineer and ex- @Yahoo in a serious relationship with programming languages and the gym.

[Figma @figma]

Config 2026 forecast: partly cloudy with a 100% chance of design deep dives

[Claude @claudeai]

Introducing Claude Fable 5: a Mythos-class model that we’ve made safe for general use.

Its capabilities exceed those of any model we’ve ever made generally available.

[self.dll @seelffff]

karpathy's CLAUDE.md hit #1 on github trending.
220,000 stars. most devs still haven't read it.

it's 65 lines.
it took AI coding accuracy from 65% to 94%.

the 4 rules inside:

→ think before coding
state your assumptions. ask when unsure. never guess.

→ simplicity first
write the minimum code that solves the problem.
no abstractions nobody asked for.

→ surgical changes
don't touch code unrelated to the request.
every changed line must trace back to what was asked.

→ goal-driven execution
turn vague instructions into verifiable success criteria
before writing a single line.

that's it.
65 lines. 4 rules. 94% accuracy.

save this before everyone else does.

[Cloudflare @Cloudflare]

Today, we are excited to introduce https://t.co/F5gmrAYGFP — a new tool to help site owners understand how they can make their sites optimized for agents. https://t.co/2xAeZlX5AI

[Cheng Lou @_chenglou]

My dear front-end developers (and anyone who’s interested in the future of interfaces):

I have crawled through depths of hell to bring you, for the foreseeable years, one of the more important foundational pieces of UI engineering (if not in implementation then certainly at least in concept):
Fast, accurate and comprehensive userland text measurement algorithm in pure TypeScript, usable for laying out entire web pages without CSS, bypassing DOM measurements and reflow

[Next.js @nextjs]

Next.js 15.4

• Turbopack Builds: 100% integration test compatibility for next build --turbopack
• General stability and performance improvements
• A preview of what's coming in Next 16

https://t.co/MJWcprRSPk

[React @reactjs]

React v19 is now stable!

https://t.co/zy12Y9Pbbv

[Next.js @nextjs]

Watch the Next.js Conf 2024 opening keynote.

[Next.js @nextjs]

Next.js 15 and Turbopack Dev are now stable.

Upgrade automatically with our new CLI and codemods.

https://t.co/H3bnigx5py

[Next.js @nextjs]

Next.js 15 RC

◆ React 19 + React Compiler support
◆ `fetch` and Route Handlers no longer cached by default
◆ Incrementally adopt Partial Prerendering
◆ New `create-next-app` design
◆ next/after (Experimental)

https://t.co/0UJkYYqLbo

[Jimmy Lai @feedthejim]

If you want to try out the new React Compiler with Next.js and don't want to wait until next week for a Next.js 15 announcement 👀, here's how.

◆ Run `pnpm install next@canary react@rc react-dom@rc babel-plugin-react-compiler`.
◆ Enable this option in your next.config.js file:
```
experimental: {
reactCompiler: true,
}
```.
◆ Verify in the React Devtools that your components are automatically memoized.
◆ Enjoy :)

Notes:
- source map line numbers are inaccurate, will fix soon
- this requires that your app migrates to React 19
- we added a bunch of breaking changes on canary, more on that in a few days

[React @reactjs]

The React Conf livestream starts now! Watch the keynote from @en_JS, @zmofei, @poteto, @_gsathya, @acdlite, and @joshcstory https://t.co/7rhnV3qMD6

[Guillermo Rauch @rauchg]

https://t.co/IzUlJQzIEI + custom design system has been achieved internally

below is a generation using the @vercel geist design system, from a basic text prompt

[AI at Meta @AIatMeta]

Introducing Meta Llama 3: the most capable openly available LLM to date.

Today we’re releasing 8B & 70B models that deliver on new capabilities such as improved reasoning and set a new state-of-the-art for models of their sizes.

Today's release includes the first two Llama 3 models — in the coming months we expect to introduce new capabilities, longer context windows, additional model sizes and enhanced performance + the Llama 3 research paper for the community to learn from our work.

More details ➡️ https://t.co/nFll4exicO
Download Llama 3 ➡️ https://t.co/Ps0OAHt0RR

[Next.js @nextjs]

Next.js 14.2

◆ Turbopack (RC): 99.8% of tests passing for `next dev --turbo`
◆ Build / Production Improvements: Reduced memory usage
◆ Caching Improvements: Configurable client-side cache revalidation
◆ Errors DX: Better hydration mismatch messages

https://t.co/5HmBItDal2

[Strapi @strapijs]

✨ 𝐓𝐡𝐞 𝐒𝐭𝐫𝐚𝐩𝐢 𝟓 𝐁𝐞𝐭𝐚 𝐢𝐬 𝐥𝐢𝐯𝐞! ✨

Big news! The Strapi 5 Beta is here! Say hi to:

📝 𝐃𝐫𝐚𝐟𝐭 & 𝐏𝐮𝐛𝐥𝐢𝐬𝐡
⚡ 𝐕𝐢𝐭𝐞 𝐁𝐮𝐧𝐝𝐥𝐢𝐧𝐠
🔌 𝐏𝐥𝐮𝐠𝐢𝐧 𝐂𝐋𝐈
🧬 𝐍𝐞𝐰 𝐀𝐏𝐈 𝐅𝐨𝐫𝐦𝐚𝐭

🌐 Full update here → https://t.co/3nxSxCPvUv

[High Performance Founder @hpfounder]

If you want to improve your mental health focus on improving your physical health.

[Csaba Kissi @csaba_kissi]

Master the ultimate CSS debugging technique 😉👇

[Julia👩‍💻 @yb_fedev]

me removing 1 line of code 🌚

[Strapi @strapijs]

🚀 Introducing Releases 🚀

"Releases" lets you bundle your content in one go.

👁️‍🗨️ Birds-Eye View
🤝 Improved Collaboration
🛡️ Reduced Errors

📖 Full Update Here → https://t.co/mhQWVXgw9e
💬 Join the Strapi 5 Waitlist Here -> https://t.co/iptJ8MdqkJ