If you're interested in the Cross-Origin Storage API, I just created a new Bluesky feed, check it out and pin it if you like it: bsky.app/profile/did:... #CrossOriginStorage

Anyone using HTTP/2 server push with libcurl? If you use this feature in libcurl, please let us know. It is being deprecated all over, including in specs, browsers and servers and I believe the time has come for us to drop it from libcurl in the future as well. So I'm curious to know if anyone […]

RUM is invaluable for the end-user ground truth, but being able to simulate/reproduce in a lab environment got 100x more useful with LLM's and agent harnesses. Agents are great at finding optimizations, even if complex (make sure to protect anything you care about with tests).

Finally, a CLI/module for testing compression dictionary deployments: blog.patrickmeenan.com/2026/07/26/t... Thanks to @programmingart.bsky.social @sergeyche.dev and @yoav.ws for not letting me continue to ignore building it 😂

Testing Compression Dictionary Deployments - Patrick Meenan's Blog

Robin Marx has been asking me for a Compression Dictionary Transport (RFC 9842) test tool for a long time (since well before AI was actually useful for this...

blog.patrickmeenan.com

I feel like the dog from "Up" with my side projects - Squirrel! Today's token-spending project - a 100% local, browser-based iOS messages search tool (from iOS backups). The Apple-provided search isn't great when you're looking for an old message. blog.patrickmeenan.com/2026/07/18/g...

Exploring iOS Backups with Golemine - Patrick Meenan's Blog

I was getting really frustrated with Apple’s search implementation for the “Messages” app (both on mobile and a MacBook) when trying to find specific message...

blog.patrickmeenan.com

If you make websites for a living, stop what you're doing and read this research by @tammyeverts.com; it shows what many of us have been saying for a long time: even if there is such a thing as "fast enough", it's generally *much* faster than you are targeting: embrace.io/blog/research-co…

New research: The Core Web Vitals thresholds you trust might be wrong for your site

Core Web Vitals data from ten leading online retailers reveals that "good" for Google may not be good enough for your users or your business.

embrace.io

This should be fun (and yes, this is what I do for fun 😂). blog.patrickmeenan.com/2026/07/11/c...

Can I create a AAA-quality game with AI on the web platform? - Patrick Meenan's Blog

Maybe? That’s the question I’m hoping to answer over the next … ??.

blog.patrickmeenan.com

It has been a busy holiday weekend burning all the tokens... Waterfall-tools can now render performance API data (including resource timing, LOAF and JS self-profiling): blog.patrickmeenan.com/2026/07/05/n...

New field browser performance and profiling tooling - rumcap - Patrick Meenan's Blog

Ever since browser vendors started exposing advanced performance telemetry APIs directly to the page, such as the Performance Timeline, Long Animation Frames...

blog.patrickmeenan.com

Really excited to be speaking about compression on the web at perf now: perfnow.nl We have 2 years of production experience with compression dictionaries now and a better understanding of where the easy wins are, where the sharp edges are and a few other compression experiments.

performance.now(); 19th and 20th of November 2026, Amsterdam

On 19th and 20th of November 2026, the seventh edition of performance.now() will take place in Amsterdam—a single track conference, covering today’s most important web performance insights.

perfnow.nl

Web developers, designers, and engineers: what Layout and Rendering features do you need from Safari? Bugs count too, I want to hear what you need?

As much flack as Gemini 3.5 Flash gets for not being in the same league as Opus 4.8 and GPT 5.5, it still finds a LOT of real issues with their work. Using all 3 in concert for "fun" projects and I stand by my earlier assertions that they work best together, reviewing each other, not picking one.

Bloomberg uses a lot of C++ & contributes to the standard as well as various industry conferences and libraries. I’m looking for an experienced engineer to join a distributed systems team in New York working on our core Deployment Infrastructure for the Bloomberg Terminal 🗽 🧵

wouldn't it be nice if sites could share a cache of common js? ... stuff like react, or vue or svelte? 👉 there's an early stage proposal for cross-origin storage which enables exactly this. there are challenges but I think it's very interesting indeed

GitHub - WICG/cross-origin-storage: Explainer for the Cross-Origin Storage (COS) API

Explainer for the Cross-Origin Storage (COS) API. Contribute to WICG/cross-origin-storage development by creating an account on GitHub.

github.com

It's happening... We've asked Chromium API owners for permission to ship The Soft Navigation work to allow measuring of Core Web Vitals for SPAs!!

IntentToShip@intenttoship.dev · last mo.

Blink: Intent to Ship: PerformanceSoftNavigation and InteractionContentfulPaint performance entry

The Chrome DevTools team are doing a "papercuts" sprint where they try to address lots of small, irritating bugs and annoyances. Reply with crbug.com links (no bug, no fix—that's the deal!) and will see what we can do. No promises though as some may be features/too big/unclear how to solve.

Has there been any movement on the legal/copyright side of AI and code (US)? I know fully-AI-generated things can't be copyrighted. Is that still the only part settled? How about AI-assisted? Commercial API subs indemnify but personal don't against copyright violation on generated code?

Want to run one-off page speed tests without setting up monitoring? Our new quick tests feature makes that easy, through the app or via our API. www.debugbear.com/docs/quick-t...

Quick Tests | DebugBear

Run one-off page speed tests against any URL without adding the page to your monitoring dashboard.

debugbear.com

I find using different core models more useful than just picking one "best" one. It's like getting different perspectives. They all find things the others miss and approach a problem differently. Models from the same family or with different prompts are too similar.

Awesome writeup. My takeaway is really not so much that Mythos is hype as the AI security tooling in general is REALLY good so don't wait (you can bet the bad guys aren't). Chances are that your project (open or closed) hasn't been as hardened as curl has.

daniel:// stenberg://@bagder.mastodon.social.ap.brid.gy · 3mo ago

#Mythos finds a #curl vulnerability yes, as in singular one. https://daniel.haxx.se/blog/2026/05/11/mythos-finds-a-curl-vulnerability/

We just sent out a TEST MAIL to our mailing list. Last year quite a few people didn't see the announcement mail and missed the early bird ticket sale. So this year we run a test first. If you're subscribed to our mailing list, please make sure you got the test mail. Or perfnow.nl/subscribe

I’ve been working with a client who runs a lot of social media and ad campaigns, so we’ve been deploying the experimental `No-Vary-Search HTTP` header. It’s amazing to see it actually working! Read all about it here: csswizardry.com/2026/05/bett...

We switched Speculation Rules on Shopify storefronts from conservative to moderate eagerness. Here's how that went: performance.shopify.com/blogs/blog/f...

Faster storefront navigations with moderate speculation rules

We upgraded Speculation Rules to moderate eagerness on all Liquid storefronts. Desktop navigations are now 285ms faster at the median, with near-zero TTFB.

performance.shopify.com

There's a new #webperf measurement API in the works! Check out this post looking at the work @jason-williams.co.uk and @jdapena.bsky.social have been putting into there Container Timing—available as an origin trail from Chrome 148 (rolling out next week). developer.chrome.com/blog/contain...

Container Timing origin trial  |  Blog  |  Chrome for Developers

Try out the Container Timing performance measurement API in origin trial from Chrome 148

developer.chrome.com

Oof, and right after the "Copy Fail" CVE is announced. Hopefully this isn't a sign of things to come as a flood of CVE patches come out. Hope those in project Glasswing are prepared. Fixing is just the first step. @cloudflare.social is going to be busy onboarding.

Hacker News 100@hn100.atproto.rocks · 3mo ago

Canonical/Ubuntu have been under DDoS for more than 15h https://status.canonical.com/#/incident/KNms6QK9ewuzz-7xUsPsNylV20jEt5kyKsd8A-3ptQEHpOd8VQ40ZQs-KD81fboQXeGZB94okNHdHBGlCv58Sw== https://news.ycombinator.com/item?id=47972213

Really interesting performance/conversion correlation study across a huge swath of Shopify sites. The usual log-normal distribution but strong impact even from 100ms deltas. Particularly interesting in that a lot of the platform is shared/controlled but still wide variety in experiences/content.

Mateusz Krzeszowiak@krzksz.bsky.social · 3mo ago

One of the most important pieces about web performance that I've ever worked on is finally live. After a few months of work, my analysis of the correlation between site speed and conversion across the entire @Shopify platform is out: www.shopify.com/enterprise/b...

I say it every year - if you're even the least bit interested or involved in web performance, this is THE place to be every year. It's the one trip I prioritize my travel budget for. The talks are awesome, but the hallway track is unbeatable. The concentration of experts in one place is insane.

performance.now() conference@perfnow.nl · 3mo ago

performance.now() 2026 is coming. Ticket sales will open in May with cheap and ultra-cheap early bird tickets. These will be announced in our newsletter first. So subscribe via perfnow.nl/subscribe perfnow.nl

Wanna measure Core Web Vitals for SPAs? It's been a long-standing gap, but one that we've been working hard to fill. We're approaching the final stages and have launched one last origin trial (🤞) as the "last call" before we ship it! More details: developer.chrome.com/blog/final-s...

Final Soft Navigations origin trial starting in Chrome 147  |  Blog  |  Chrome for Developers

Take a last chance to try out the Soft Navigations API before release with this final origin trial.

developer.chrome.com

I'm very excited about this! Have seen some really significant impact in our tests. With the sizes of websites and JS payloads continuing to increase, this is both important and impactful.

Cloudflare@cloudflare.social · 4mo ago

Today, we’re excited to give you a sneak peek of our support for shared compression dictionaries, show you how it improves page load times, and reveal when you’ll be able to try the beta yourself. https://cfl.re/42egXfC

Really excited to see the support for compression dictionaries that @cloudflare.social is working on. Great background on the feature as well.

Cloudflare@cloudflare.social · 4mo ago

Today, we’re excited to give you a sneak peek of our support for shared compression dictionaries, show you how it improves page load times, and reveal when you’ll be able to try the beta yourself. https://cfl.re/42egXfC

Hmm, with Devtools protocol access, this could fill in for a synthetic testing pipeline. Might be interesting to hook it up to see if it can provide useful testing infrastructure. Obviously not as clean as real devices but much more flexible.

Cloudflare@cloudflare.social · 4mo ago

Browser Rendering is now Browser Run, with Live View, Human in the Loop, CDP access, session recordings, and 4x higher concurrency limits for AI agents. https://cfl.re/4sFYx2j