Optimal UX – Server-side A/B testing that runs before page load
Optimal UX runs experiments directly on the server side through a Cloudflare Worker, meaning variations are applied before the page even reaches the browser. The core idea is to intercept and modify the HTML stream at the edge, which eliminates client-side overhead. For websites using Cloudflare, it's just a matter of installing the Smart Agent. The same agent works seamlessly with React, Vue, and other frontend frameworks when client-side testing is needed. One unexpected benefit that emerged during development was the ability to quickly apply HTML patches. This turned out to be super…
What it does
In the maker’s words, at launch
Optimal UX runs experiments directly on the server side through a Cloudflare Worker, meaning variations are applied before the page even reaches the browser. The core idea is to intercept and modify the HTML stream at the edge, which eliminates client-side overhead. For websites using Cloudflare, it's just a matter of installing the Smart Agent. The same agent works seamlessly with React, Vue, and other frontend frameworks when client-side testing is needed. One unexpected benefit that emerged during development was the ability to quickly apply HTML patches. This turned out to be super useful for SEO tweaks - you can update meta tags, headings, or content structure without deploying new code. Tech stack: -Edge computing (Cloudflare Workers) - Streaming HTML parser - Framework-agnostic client library (~3KB gzipped) Would love feedback from anyone doing A/B testing at scale. This is my first time building something for edge computing and I learned a ton about HTML streaming and performance optimization. I'm particularly curious: - Has anyone else encountered performance issues with client-side A/B testing tools? - For those running tests on high-traffic sites, how do you handle the performance impact? - What's your experience with edge computing for similar use cases?
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I was at FB/Meta from late 2013 to early 2023, mostly working in the compiler/runtime spaces. I got hit in the spring 2023 layoff wave. I immediately started making games in my newfound free time (a lifelong interest, and I even worked in AA(A?) back ca. ~2000), and in October 2023 I stumbled upon the idea of a roguelike pachinko/plinko game inspired by Luck Be A Landlord. Things snowballed quickly, I started talking to publishers, then worked like crazy through all of 2024, almost the hardest I've ever worked in my career, and launched the game in December 2024. It's sold…
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