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 236 articles on this blog. Find them all on the blog page.

15 October, 2016
Pure CSS Content Filter
10 October, 2016
Pragmatic, Practical, and Progressive Theming with Custom Properties
30 August, 2016
Refactoring CSS: The Three I’s
20 June, 2016
Speaker’s Checklist: Before and After Your Talk
1 June, 2016
Improving Your CSS with Parker
8 May, 2016
The Importance of !important: Forcing Immutability in CSS
25 February, 2016
Mixins Better for Performance
21 February, 2016
Managing Typography on Large Apps
14 September, 2015
White October Events Workshop Partnership
5 August, 2015
BEMIT: Taking the BEM Naming Convention a Step Further

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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ITCSS – coming soon…

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Infoshare: Gdańsk (Poland), May 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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