State of Web Performance in 2026 - with Google Developer Expert

Measuring detailed web performance and Google’s Core Web Vitals in 2026, and how can AI + MCP help developers turn that data into actionable improvements?

Core Web Vitals have become an important part of how we talk about web performance, but what are we actually measuring, and why did Google introduce these metrics in the first place?
In this talk, we’ll look at the Core Web Vitals in 2026, what each metric tells us about the real user experience, and how they translate technical performance into technical UX. We’ll also briefly look at where Core Web Vitals overlap with SEO, and why good performance goes beyond simply chasing a Lighthouse score.
From there, we’ll move into real-user monitoring and see how detailed field data can help developers understand what is actually happening on their websites, across real users, devices and pages. And how you can spot which exact third parties are messing up your site's performance.
Finally, we’ll explore how RUMvision, a web performance platform built in Groningen, exposes its data through MCP, allowing developers, merchants and other stakeholders to talk directly to their performance data and get answers without having to dig through dashboards.
Time table, approx., can still be changed:

18:00 – Doors open with food and drinks

18:45 – Welcome and opening remarks

19:00 – Talk 1: Karlijn Löwik

19:55 – Short break

20:00 – Talk 2: Erwin Hofman

20:55 – Drinks & Networking

22:00 - End

Agenda

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Speakers

Erwin Hofman - co-founder + CTO RUMvision (Google Developer Expert)

Erwin Hofman moved from building his own fast CMS to helping e-commerce agencies and merchants with web performance optimization as a Google Developer Expert. He is also the co-founder of RUMvision, providing merchants with real-time, detailed Core Web Vitals insights.

Karlijn Löwik - RUMvision (CEO and co-founder)

Karlijn Löwik is CEO & Co-founder of RUMvision, on a mission to make web performance a business priority for every eCommerce company. Based in Groningen (NL), she’s an international web performance speaker, RUM-advocate, and champion for women in tech. She serves as co-chair for the RUM W3C Group and as a board member of Mage-OS NL. She coined the term Sitespeed User Experience (SUX) …

Hosted By

Tymen Steur, GDG Organizer

Rutger Roffel, Head of AI

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Partner

New Nexus (https://newnexus.nl/)
New Nexus supports with a venue, food, drinks and Meetup costs.

New Nexus is a platform for (IT) professionals who want to make a difference in their work, in the company and in society. Without hierarchy and other hassle. We believe that you grow by sharing and that tomorrow is more important than today's profits. We work with organizations that want to continuously innovate. We build software for them, convert data into valuable information and supervise improvement processes.

IT's our DNA

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Complete your event RSVP here: https://gdg.community.dev/events/details/google-gdg-groningen-presents-state-of-web-performance-in-2026-with-google-developer-experts-and-web-performance-leaders/.