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Joined May 2021
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WebPerformance Report retweeted
We enabled streaming for @Shopify storefronts. The layout head reaches the browser before the template finishes rendering.
Median-store TTFB down 29% at p75, 21% at p90. FCP and LCP down 2–6%. No theme changes needed*.
performance.shopify.com/blog…
WebPerformance Report retweeted
Announcing skillzero: save tokens by keeping skill names + descriptions out of agent context for skills you only use as /-commands.
Experts like @addyosmani & @mattpocockuk all have mentioned this in the past: Don't accumulate skills you never use. You pay for them, they pollute context and make agents less reliable in actually using the ones you want it to use.
skillzero changes this, as it allows you to split skills into:
- 👻 hidden skills (the /-cmds)
- 📚 collections (bundled by topic)
- regular skills (stay in context)
Of course open-source.
WebPerformance Report retweeted
By popular demand, I added a capabilities page to What PWA Can Do Today, which lists all capabilities on one page and indicates for each one if it's supported on your device.
You can filter by support and search for capabilities.
whatpwacando.today/capabilit…
WebPerformance Report retweeted
My Pixel Pioneers talk is on Youtube now!
I give a brief introduction to page speed and then dive into different network throttling methods in Lighthouse, DevTools, and other tools.
youtube.com/watch?v=KO02JZn_…
WebPerformance Report retweeted
I just added three new tools to the PWA Today MCP server 🚀
- list_pwa_audits
- compare_pwa_audits
- get_pwa_audit_entitlement
You can now let your agent retrieve a list of your audits, compare two audits, and see the status of your plan.
The PWA Today Runtime Audit tests your PWA under real-world conditions and finds issues before your users do
🧵1/2
pwa.today
WebPerformance Report retweeted
Software fundamentals still matter with agents because tradeoffs still exist.
Agents will pick a tradeoff. Expertise is knowing the menu - latency, consistency, cost etc - and steering the agent to the one that's right for your system.
WebPerformance Report retweeted
Can recommend. I've made the switch at Framer:
• Paint: 127ms → 0ms
• RasterTask: 440ms → 0ms
• Main-thread time: 276ms → 6ms
• Compositor thread: 146ms → 351ms
→ work moves off main thread. this can improve INP too!
Text shimmer animations are usually very CPU intensive (~20% for one line of text). Animating background-position is not GPU accelerated, so the browser re-paints every frame.
I found an alternative using a CSS mask which only animates a transform. Reduces CPU usage to < 2%. codepen.io/editor/devongovet…
WebPerformance Report retweeted
I’m thinking about banning Claude code at Shopify until they change their mind and read AGENTS.md and .agents/skills etc.
Insisting on only reading CLAUDE.md sometimes leads to split brain problems when different team members use different tools. Just unnecessary.
WebPerformance Report retweeted
WebPerformance Report retweeted
CrUX data isn't 28 days old. It's two days old
What takes 28 days is for the window to fully turn over, and that's why p75 sits still for two weeks and then drops all at once
I wrote about it, with two interactive demos
joanleon.dev/en/crux-28-day-…
#WebPerf #CoreWebVitals #CrUX
WebPerformance Report retweeted
Want to access your page speed data with Claude Code? We've just published a guide on how to connect Claude Code to our MCP server. debugbear.com/docs/claude-co…
WebPerformance Report retweeted
He migrado un proyecto de Next.js a Astro.
La diferencia de rendimiento de salida es importante.
WebPerformance Report retweeted
We enabled automatic addition of loading="lazy" for shopify.dev/docs/api/liquid/… 🚀 On pages using videos, we're seeing 75% reduction in downloaded files and 1.23MB/78% less data transferred! For now only in Chrome, but support in other browsers is coming.
WebPerformance Report retweeted
Every time a marketing pixel, growth experiment, or third-party script gets pushed into production without a clear performance budget, your company is effectively budgeting for slowness.
Performance is a structural constraint every department must respect, not a downstream cleanup task for engineering.
Stop accepting the drag: crystallize.com/blog/fronten…
WebPerformance Report retweeted
So true
Many people think any given ML project is 99% training.
In reality, it’s 50% evaluation, 40% data cleaning, 8% integration, and 2% training.
The first two set the noise floor for learning. No ML magic matters; the model cannot lower the noise floor, as that’s the optimal bound of Shannon encoding of your data.
Thus, not a single day goes by without me thinking about ontology. Even the old labels have to be constantly reviewed.
WebPerformance Report retweeted
🆕 Introducing the MDN MCP server!
Bring MDN's docs and browser compat data straight into your AI agent or IDE for accurate, up-to-date answers about the web platform.
No more outdated guesses from training data.
Learn more 👇
developer.mozilla.org/en-US/…
ALT A headline Introducing MDN MCP server above a terminal window titled Light-dark CSS function for images, showing a prompt asking how to use the light-dark() CSS function for images and which browsers support it, with a note that the mdn tool was called 4 times, followed by an answer explaining that light-dark() takes two image values and works anywhere an image is accepted. The MDN logo appears on the right.
