About Me

Felix Arntz headshotHi there! I’m Felix Arntz, a software engineer and open-source contributor focusing on the open web. I’ve been building things for the web for more than a decade, and I’m particularly passionate about the WordPress project, and making WordPress sites fast.

I am currently a Senior Software Engineer at Google, in a team called Galaxy where we enhance performance and advance progressive web technologies in WordPress and the overall CMS ecosystem.

Additionally I am a core committer to the WordPress open-source project, and I am currently a team rep for the WordPress Performance Team. I have spoken at over 20 WordCamps and other WordPress events.

A little history

I started building websites as a freelancer, which quickly evolved into more backend focused projects, building web applications with custom WordPress plugins at their core.

Since mid-2015, I have been heavily involved with contributing to the WordPress Core software. With WordPress version 4.6 I was recognized as a noteworthy contributor for the first time, and since November 2016 I have been a Core Committer.

Felix Arntz Yoast avatarBecoming more active in the broader WordPress community allowed me to collaborate with several companies in the ecosystem. This led me to eventually focus on contracting for these companies, in addition to maintaining my own client relationships. Some of the WordPress companies that I worked with during my freelance career are Yoast (I even have a Yoast avatar as you can see!), WP Engine, Aspen Grove Studios, and Usability Dynamics.

In 2018, I joined Google, from the very beginning in a CMS focused team primarily building WordPress solutions. For several years I was the lead engineer of the Site Kit plugin for WordPress, building the plugin from the ground up and growing it to over 4 million active installations. In late 2021 I shifted my focus, co-founding the WordPress Performance Team and subsequently being heavily involved in its projects to enhance performance of the WordPress project, to benefit all websites using the CMS.

What I enjoy when building software

I’m equally enthusiastic about clean software architecture as I am about web performance. Whichever projects I’m working on or contributing to, my objective is to steer them towards these goals.

Implementing the components of a piece of software (e.g. a WordPress plugin) in a decoupled and reusable manner, and clearly scoping the software’s public API makes the entire software easier to maintain. This enables quick iterations with little risk of bugs. It even makes it possible to experiment without risking the integrity of your software.

This is particularly important in my eyes when building within the WordPress ecosystem: The endless combinations of plugins, themes, and other infrastructure can easily lead to incompatibilities between them, if the pieces are put together too pragmatically without consideration for the ecosystem and future maintenance.

Building software from decoupled components with distinct responsibilities also facilitates building performant software. By selectively loading only what’s needed you avoid overhead and keep the backend footprint low. From there, implementing interactive features following frontend performance best practices is almost a breeze, if you know what to pay attention to.

Outside of software engineering

When I’m not coding, I am passionate about electronic music production, and I love going for long walks. You may also find me running around the world, or geeking out on movies, Mexican food (especially 🐟🌮), and beer. My guilty pleasure is Mountain Dew.

Felix Arntz drinking a Mountain Dew at Google Mountain View
Myself enjoying a Mountain Dew in Mountain View at the Google campus