Sander van Surksum
sandervs.bsky.social
Sander van Surksum
@sandervs.bsky.social
Web performance enthousiast - father of 4 daughters - parttime muralist
founder of https://www.iron-out.io
Reposted by Sander van Surksum
Telescope, the new cross-browser performance testing agent I mentioned at #perfnow that we @cloudflare.social have open-sourced is here: github.com/cloudflare/t...

We want this to be a tool the entire community is able to contribute to and benefit from, so please help us make it better!
GitHub - cloudflare/telescope: Cross-browser web performance testing agent
Cross-browser web performance testing agent. Contribute to cloudflare/telescope development by creating an account on GitHub.
github.com
October 31, 2025 at 2:15 PM
Reposted by Sander van Surksum
Schedule schedule on the wall, who has the best line-up of them all?

perfnow.nl/schedule.html
September 30, 2025 at 12:25 PM
🚀 Quick Performance Tip:
Not every conversion issue is a checkout issue.

Slow pages earlier in the flow mean fewer baskets and fewer orders.

#pagespeed #CRO #ux #webperformance #ecommercegrowth #digitalexperience
September 29, 2025 at 2:27 PM
🚀 Quick Performance Tip:

Most sites do not lose customers at checkout. They lose them to small frictions earlier in the flow.

A blank screen, a shifting button, a slow filter. Each breaks trust. And trust is what sells.

#ecommerce #uxdesign #webperformance #CRO #pagespeed
September 26, 2025 at 12:19 PM
🚀 Quick Performance Tips (series intro):
Performance still is not a hygiene factor in e-commerce. But it should be.

Over the next few weeks I will share a short series on how flow, friction and trust shape user behaviour and sales.

#ecommerce #webperformance #conversionrate #digitalgrowth
September 25, 2025 at 5:49 PM
Reposted by Sander van Surksum
performance.now(), the web performance conference, 30th and 31st of October, Amsterdam. Single track, the best speakers in the industry, plenty of your performance-mad peers around to have fascinating conversations. What's not to like? Let's introduce our speakers ...
perfnow.nl
performance.now(); 30th and 31st of October, Amsterdam
On 30th and 31st of October, 2025, the sixth edition of performance.now() will take place in Amsterdam—a single track conference, covering today’s most important web performance insights.
perfnow.nl
June 25, 2025 at 12:35 PM
Google's new CrUX API updates offer deeper performance insights:

🚀 LCP Image Subparts – Find what’s slowing your LCP
📸 LCP Resource Type – Know if LCP is text or images
🌐 RTT Data – Understand network latency better

Optimize your site with these new metrics! #webperf #SEO #userexperience
February 12, 2025 at 8:04 AM
Two months ago, I spoke about INP (Interaction to Next Paint) and the scheduler.yield() at @frontmania.bsky.social -- and the feedback is in... 🥈 I was rated the 2nd best speaker at the event! 🌟 🥳 🎉
December 6, 2024 at 8:28 AM
2 months ago, I gave a talk at @frontmania.bsky.social where I showcased a demo I created to highlight INP issues on a PDP page when switching colors. It showed how small delays can frustrate users and hurt conversions. Check it out: inp-demo.netlify.app/product-detail #webperf #INP #performance
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inp-demo.netlify.app
November 26, 2024 at 2:14 PM
Reposted by Sander van Surksum
Yesterday during my #perfnow talk, I mentioned the Web Performance Slack. If you’d like to join the Slack, use this link before Nov 25: join.slack.com/t/webperf…
November 15, 2024 at 8:39 AM
We finally know what Erwin looks like without his hat! #perfnow
November 15, 2024 at 11:29 AM
The golden rule of performance improvement: "Always measure the impact of your changes." #perfnow
November 15, 2024 at 11:21 AM
Reposted by Sander van Surksum
Took 2 mins at #PerfNow to talk about the RUM Community Group in W3C for anyone doing RUM. It's free and easy to join if you're interested! www.w3.org/community/ru...
November 14, 2024 at 2:01 PM
On my way to @perfnow.bsky.social excited to catch all the talks! #perfnow
November 14, 2024 at 7:48 AM
It’s the 5th anniversary of @perfnow.bsky.social, one of the most well-organised events with an amazing audience! 🎉 First stop today: WebPerfDays Unconference at Google Amsterdam. Huge thanks to everyone who made this possible—let’s connect if you’re there or catch the livestream! 🚀 #perfnow
November 13, 2024 at 8:41 AM
The 2024 Web Almanac just dropped! Full of real data on Core Web Vitals, JavaScript, images, and more. It’s perfect for helping you improve your site with real numbers. Check it out!
almanac.httparchive.org/en/2024/

#pagespeed #webperformance
November 12, 2024 at 9:27 AM