2025 conference photos are up perfnow.nl/2025/pix/pho... (though I need to consult a speculation rules expert at some point)

And the performance.sync() videos, the Wednesday pre-party, are also live. www.youtube.com/@WebConferen...

Team photos are up. perfnow.nl/teams-2025.h...

A little aftermovie to whet your appetite. www.youtube.com/watch?v=ByOC...

Here you go! My first perf now as a speaker… it’s was amazing 🤩 docs.google.com/presentation...

I shilled a javascript framework at a web perf conference and came out mostly unscathed, AMA

performance.now() 2026 will take place on 19th and 20th of November 2026. #perfnow.

Unsurprising revelation from #perfnow: @rich-harris.dev really is ruddy good at demonstrating interesting concepts. His @svelte.dev is demo is terribly compelling.

"Family. The #webperf community is family." - Dom Toretto @rich-harris.dev #PerfNow

@rich-harris.dev might have the best demo app I have ever seen 😁 at #perfNow

"SSR is about ~SEO~ performance" - @rich-harris.dev #perfnow #WebPerf

#perfnow absolutely fantastic and compelling demos from @rich-harris.dev but I'm trying to resist concerns on his preference for tabs over spaces...😂

@perfnow.nl for whoever asked that question about Sec-Purpose it DOES get set on sub-resources for prerendered speculations. Not just the document. #perfnow

It’s an honor to see my company #speedkit mentioned on stage at #perfnow by a web performance VIP and ambassador such as Barry @tunetheweb.com Pollard. 😊 Congrats to the Speed Kit team who implemented speculation rules in such an effective way in our product!

Making Sense of Long Animation Frames… The slides from my #PerfNow talk are available on Notist noti.st/andydavies/9...

Here are mine: speakerdeck.com/ethangardner...

Interesting! Etsy implemented speculation rules and got these results: 👍 Time to First Byte on the listing page improved 23.6% 👍 First Contentful Paint improved 20.7% 👍 Largest Contentful Paint improved 21.1% 👍 DOMContentLoaded improved 20.4% #PerfNow #webperf www.etsy.com/codeascraft/...

#PerfNow has incredibly interesting talks. Anyone who's serious about performance should join. Proud that we at @framer.com are sponsors.

Here are mine! Thanks for a wonderful conference 🫶🏻 bit.ly/a11y-perfnow25

Always, always happy to see @yoav.ws get a shout-out. So much incredible work has happened because of him. Most recent example—speculation rules in WebKit. #perfnow

Super talk from @tunetheweb.com on Speculation Rules. Been nervous about using them for fear of false positives on things like Google Analytics. The upcoming prerender_until_script logic sounds like exactly what I need - you'll benefit from fetching subresources, but won't execute scripts. #PerfNow

@marcysutton.com @mmocny.com @andydavies.me @ethangardner.com @inesakrap.bsky.social @csswizardry.com @michael-hladky.bsky.social @adevnadia.bsky.social Could you please post a link to your conference slides so we can share it with our audience? Thanks!

I appreciate everyone at #perfnow letting me have my "old man yells at cloud" moment this morning. Slides are now up: noti.st/tkadlec/3imH...

There's a sight to see, freshly published in time for #PerfNow. Talk by @tunetheweb.com , an excellent walkthrough on how to get the most out of a truly powerful tool www.etsy.com/codeascraft/...

A wise man once said... "Simple to use, progressive enhancement, built in APIs are the best!" - @tunetheweb.com Yep, he's onto something. loading=lazy and fetchpriority=high are wonderfully simple 'cheat codes', and some of my favourite additions to the world of #webperf. #PerfNow

One of my favourite pictures from 2023 #perfnow @tunetheweb.com @andydavies.me

Hi #perfnow! I’m a first-year student from the Amsterdam University of Applied Sciences representing Frontend design and development. I’m in awe by all the amazing talks and knowledgable attendees!

Halloween at #perfnow, pirates and vampires. A.k.a sword fight, the sequel. Or... How RUMvision slayed Akamai😇😆 (jk)

“We should treat accessibility as something that is structural or baked in or part of the DNA, if we want to be successful” — says @marcysutton.com at #perfnow “Don’t treat it like trying to put chocolate chips into a cookie after it is baked” I love this framing!

Nextferatu... @programmingart.bsky.social #perfnow

@adevnadia.bsky.social is not afraid to shout from the stage why she loves SPAs (while acknowledging their drawbacks) and on behalf of all FE devs, I would like to thank her for her bravery 🫡🙏🏻 #perfNow

For #PerfNow folks (and other folks who are interested in front-end #webperf)… you should know that @adevnadia.bsky.social has written this amazing resource. www.getwebperf.com

Thanks @mmocny.com for the container timing shoutout and stealing my low effort diagram 😂 Great talk @ #perfnow

@mmocny.com talking about some super cool new measurements coming to Chrome - such as the equivalent of LCP but for 'soft' navigations like those in SPAs. That has the potential to start measuring a huge blind spot affecting a very significant portion of the web. #PerfNow #webperf

@programmingart.bsky.social and I are on the same page for a lot of things but I'm still learning from the master on how much drip a Halloween costume should have #perfNow

@mmocny.com doing an excellent job of visually explaining how interactions are measured between an MPA and a SPA. #perfnow

I have been sooooo looking forward to this! SPA heuristics are gonna be such a huge step forward for measuring perf on the web and finally having hard data on the perf impact. @mmocny.com #perfnow

#perfnow I think Safari Tech Preview just updated and now it support INP. cc @tkadlec.bsky.social

Huge thanks to @andydavies.me for mentioning the LoAF Helpers WebPerf Snippet at @perfnow.nl! Honored to be part of the amazing Web Performance community 🫶 🔗 webperf-snippets.nucliweb.net/Interaction/... #WebPerf #PerfNow #Performance #LoAF #INP #CoreWebVitals

@tkadlec.bsky.social is being quite stubborn at #perfnow @perfnow.nl 2025

We’re shipping more and more and more JavaScript. And the problem is only going to get worse as most AI-generated web pages are built on JS frameworks. @speedcurve.com performance expert @andydavies.me at #PerfNow

WOW, @tkadlec.bsky.social totally exposes how lopsided the equation with AI crawlers is right now at #perfNow

One of the newest job descriptions "vibe coding cleanup specialist" techcrunch.com/2025/09/14/v... #perfnow

When you make a glib comment in your announcement to encourage people to take their seats at a conference and throw unjustified shade at @tkadlec.bsky.social which is then committed to writing. #perfnow

For #PerfNow folks who want to go even deeper on Long Animation Frames, @andydavies.me wrote the definitive guide. www.speedcurve.com/blog/guide-l...

Some catchy takeaways at #perfnow today

First talk of #perfnow day 2 and @timkadlec.bsky.social is already attacking me 🥲

@tkadlec.bsky.social speaking my language on stage at #perfnow. #stubbornempathy #pragmagical

@tkadlec.bsky.social kicking off @perfnow.nl day 2! #perfnow