Jonathan Klein

Jonathan Klein
Director of Engineering , Attend

Website | @jonathanklein

Jonathan is a software engineer at Etsy, where he focuses on solving web performance and scalability challenges. Prior to working at Etsy he spent almost four years at Wayfair, where he led the team that converted the primary tech stack to PHP/Lighttpd/FreeBSD. He started and organizes the Boston Web Performance Meetup Group, and he contributes to a few open source projects, including the HTTPArchive and CSSLint. Jonathan blogs regularly at and can be found on Twitter at @jonathanklein.


Web Performance
Location: King's Suite
Jonathan Klein (Attend)
Average rating: ***..
(3.87, 30 ratings)
WebPagetest is an awesome tool, but out of the box there isn't an easy way to run large numbers of tests and get performance trends over time. This demo will show off wpt-script, a tool that Etsy wrote and open sourced to make this process much easier! Read more.
Web Performance
Location: Palace Suite Level: Intermediate
Jonathan Klein (Attend)
Average rating: ****.
(4.32, 19 ratings)
We’ve all heard about the new standards that are being developed to speed up the web - SPDY, WebP, Client Hints, pre-fetching, and more. Unfortunately, support for these technologies is weak across browsers and CDNs, which hamstrings implementation efforts. This talk will quantify the value of these optimizations, and provide a suggested path for driving adoption. Read more.


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