CGNwebperf #27: Tim Vereecke und Christian Lorenz

Cologne Web Performance Optimization Group
Cologne Web Performance Optimization Group
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Im Mediapark 5 · Köln

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Raum Rom, 1. Stock

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Hallo Webspeeder,

ich möchte euch herzlich zu unserem nächsten Meetup einladen. Es wird zwei Talk‘s geben:

1.) Tim Vereecke: Data(s)haver strategies

More and more people are making use of the data saver mode built into their browser (Opera Turbo, Yandex Turbo Mode, Chrome Data Saver). As website owners we should listen and serve a lightweight version when the data-saver request header is present.

I’ll share the approaches, trade-offs and results from my journey shaving off bytes on With around 30K daily visitors it is the largest scale modeling website in the world.

I have been using performance budgets for many years, but the new light version (consuming 50% less bandwidth on an iPhone) unexpectedly broke this model. I will also address how the use of a data budget matrix solved the issues I faced.

> Tim Vereecke (@TimVereecke) loves speeding up websites and likes to understand the technical and business aspects of WebPerf since 15+ years. He is a web performance architect at Akamai and also runs : the largest (and fastest) scale modeling website on the planet.

2.) Christian Lorenz: Was soll das denn? CSS in JS.

Alle paar Monate mal was Neues. CSS in JS hört sich erstmal total unsinnig an, könnte aber für den Webperformance orientierten Entwickler eine echte Alternative sein. In diesem Talk werden Vor- und Nachteile des CSS-in-JS Stacks vorgestellt, besprochen und wahrscheinlich auch diskutiert.

> Christian Lorenz ( "Ob Backend, Frontend oder beides zusammen. Als Kölsche Jung isser sich vor nix Pfui."