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.

5 September, 2010
Set then unset (or reset...?)
31 August, 2010
Zebra-striping rows and columns
9 August, 2010
Semantics and sensibility
7 April, 2010
Building sites without using IDs or classes
8 March, 2010
30 days without an iPhone
2 March, 2010
Moving forward is holding us back
2 March, 2010
A quick note on border radius
24 February, 2010
Type tips—quick tips on all things web typography
11 February, 2010
Multiple column lists using one <ul>
4 February, 2010
Upside down domains—registering an international domain name

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.

Connect

Projects

ITCSS – coming soon…

Next Appearance

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

Learn:

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.

Start a Conversation

.site-nav__list { content-visibility: visible; }

Audits

Consultancy

Training