Web Performance Optimisation, Consultancy, and Engineering

Trusted by:

Harry gave the team a strong footing for identifying performance issues on iPlayer. With his knowledge, we were able to roll out quick fixes to our audiences without the need for big rewrites, all within just two days.
Matthew Burrows, BBC iPlayer
Harry helped our team level up their scalable CSS architecture skills, and to say that he had a large impact on our work is an understatement. We can’t recommend him enough.
Addy Osmani, Google
Harry’s workshop was excellent; we left with tons of new ideas and techniques to improve both the CSS architecture and overall performance of Behance and Adobe Portfolio.
Jackie Balzer, Adobe
There’s a short list of people I whole-heartedly recommend for detailed performance work; Harry is right up there at the top.
Tim Kadlec
The CSS architecture I learned from Harry on the NHS project has changed the way I work. Bravo!
Josh Nesbitt

Web Performance and Site-Speed Insights

There are 237 articles on this blog. Find them all on the blog page.

21 June, 2012
The open/closed principle applied to CSS
12 June, 2012
Single-direction margin declarations
15 May, 2012
Keep your CSS selectors short
29 April, 2012
Front-Trends 2012
28 April, 2012
The single responsibility principle applied to CSS
20 April, 2012
My HTML/CSS coding style
16 April, 2012
Comments on CSS Wizardry
13 March, 2012
Hacker News rebuttal
29 February, 2012
Pragmatic, practical font sizing in CSS
12 February, 2012
Breaking Good Habits—The Digital Barn

Hi there, I’m Harry Roberts. I am an award-winning Consultant Web Performance Engineer, designer, developer, writer, and speaker from the UK. I write, Tweet, speak, and share code about measuring and improving site-speed. You should hire me.

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ANWB Front-End Summit: The Hague (Netherlands), June 2025

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I help teams achieve class-leading web performance, providing consultancy, guidance, and hands-on expertise.

I specialise in tackling complex, large-scale projects where speed, scalability, and reliability are critical to success.

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