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Obnoxiously Slow Endpoints

Nicole Sullivan (Stubbornella)
Average rating: ***..
(3.88, 33 ratings)

In service oriented applications, you interact with endpoints you don’t directly control. Those endpoints can be fast or slow, reliable or unreliable, or any combination of those. On a recent project, we interacted with an endpoint that took 12 hops to get a response back. Six out, and six back. It was also unreliable, failing as often as not.

In this session, Nicole will describe the journey her team took to craft a solid user experience in spite of these constraints. You will learn how killing a single modal dramatically improved the user experience and why measuring the endpoints was an important first step. She will also cover:

  • CSS Animation strategies
  • Designing for intermediate states (what if the save takes 15 seconds?)
  • Non-blocking design
  • How to wean yourself off spinners (and when not to!)
  • Requesting less expensive data (do you really need all that?)
  • Breaking up requests
  • Making requests asynchronous
  • Taking advantage of angular js data-bindings (and the limitations we found)
  • Caching and pre-caching data
  • Testing your designs with slowness in mind

Finally, we’ll talk about how we ultimately improved the endpoint (less hops!) to really make the user experience come together.

Photo of Nicole Sullivan

Nicole Sullivan


Nicole is an evangelist, front-end performance consultant, CSS Ninja, and author. She started the Object-Oriented CSS open source project, which answers the question: how do you scale CSS for millions of visitors or thousands of pages? She also consulted with the W3C for their beta redesign, and is the co-creator of, an image optimization service in the cloud. She is passionate about CSS, web standards, and scalable front-end architecture for large commercial websites.

She co-authored Even Faster Websites and blogs at