Sub second

Written by Joshua Nelson, a developer at Airbnb who wants to make the web faster for everyone. Opinions expressed are my own.

Get emails from me about once a month when I post new content, focusing on performance, front end technology, and engineering.

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I create projects for learning and fun. Check them out.


Better benchmarking

October 10, 2022New post

It's easy to produce benchmarking data that fits your desired hypothesis. To reduce bias and make accurate benchmarks, set up your test in a realistic way, and analyze your data scientifically.

The dangers of Apdex

April 02, 2019

Apdex is a universal measurement of performance, but don't be fooled into thinking that's enough.

Protecting performance

March 10, 2019

Performance is a problem. The evidence is clear – performance affects your business goals, your user’s happiness, and it impacts areas with poor connectivity even more than you might expect.

Choosing a metric

March 10, 2019

Performance is important. We need to choose the right metric to measure it.

Measuring performance

March 10, 2019

Performance is a problem. The evidence is clear – performance affects your business goals, your user’s happiness, and it impacts areas with poor connectivity even more than you might expect.

The case for performance

March 10, 2019

The median page load time for a website on a mobile device is 15.6 seconds.