Sentinel: Your Web-Performance Watchman

A New Year, a New Focus

Written by on CSS Wizardry.

Table of Contents
  1. The State of Web Performance
  2. Performance Consultancy

For the longest time, I’ve been known for my work in the CSS field. And expectedly so: with a site called CSS Wizardry hosting well over a hundred-and-fifty articles about the stuff, over sixty conference appearances almost all covering the topic, and numerous newsletters and screencasts about it, it’s easy to see why.

Over the past three years of consultancy work I’ve helped some amazing people level up their CSS architecture, but there’s also been a lot of other work that’s happened alongside it. With a great majority of these clients, we’ve also taken a look at how their sites actually perform both over the wire and on users’ devices. I’ve helped companies large and small focus entirely on optimising performance, and it’s something I am very serious and passionate about.

It’s something I am keen to do more of.

The State of Web Performance

There is a short list of people I whole-heartedly recommend for detailed performance work and Harry is right up there at the top.

Tim Kadlec

I feel like we have a problem: as technologies improve, tools are becoming more costly; as connectivity becomes more ubiquitous, pages are growing heavier; and as more and more people are coming online, the web is getting slower. It’s like there are two workstreams flowing in opposite directions.

The people tasked with building websites and applications often forget that they tend to do so in a bubble of wired connections and powerful machines, failing to understand the real-world conditions in which people use their products. The next Billion (with a capital B) internet users certainly do not enjoy the increasingly Westernised conditions for which we seem to build things.

The more I’ve traveled, worked with clients, or talked with developers, the more apparent it has become that there is a skills and/or knowledge gap across companies: from executive level, all the way down to development teams. A conversation I had recently served to highlight this issue further. Whilst discussing the intricacies of a certain performance (anti-)pattern, a developer brazenly claimed …let’s assume an 8MB connection and 50ms RTT.. It’s exactly these lines of thinking that I want to help to change.

But! The good thing about being in this position is that it gives us a lot of room for improvement. Let’s make it better.

We hired Harry to provide performance consultancy on a high profile and highly trafficked website for one of Europe’s most recognised authorities. His detailed and intricate knowledge […] allowed him to improve performance by over 400% […] he managed to optimise and restructure things in such a way that load times went from around 6.25 seconds to just 1.5.

Tom Faller, Parallax

Performance Consultancy

All of this to say… In 2017 (and indeed beyond) I want to begin putting more focus on my performance work. Of course—of course—I will still be doing my usual CSS architecture work, but if you:

  • want someone to audit your site’s current performance: it helps to know where you’re at right now;
  • need someone to explain the importance of performance to stakeholders: convincing clients and managers about the importance of performance is hard;
  • are an ecommerce company wanting to improve performance: speed and conversion rates are very, very closely linked;
  • would like performance training and workshops: enabling your team to make websites fast, and keep them that way;
  • or need any help at all with making your site, product, or app fast: then we should talk.

You want it done; I want to do it.

Harry’s focused, practical approach allowed us to implement significant changes which improved our user experience and overall performance dramatically. I recommend him wholeheartedly.

Rich Fogarty, Concrete Playground

Did this help? We can do way more!

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.

You can now find me on Mastodon.

Suffering? Fix It Fast!


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I am available for hire to consult, advise, and develop with passionate product teams across the globe.

I specialise in large, product-based projects where performance, scalability, and maintainability are paramount.