Sentinel: Your Web-Performance Watchman

Let’s work together

Written by on CSS Wizardry.

Table of Contents
  1. Featured case study: NHS

Almost three months ago I handed in my notice at Sky, where I’d spent the last two-and-a-bit years as a Senior Developer. My time at Sky has been amazing; I learned so much about big sites, architecture, scalability, performance, big teams, maintenance, working on products and a lot, lot more. Sky has been great – and the most formative work of my career so far – so choosing to leave was an incredibly difficult decision; one which took a long time to make. You can read a lot more about that in my (now infamous) post, Make it count, from back in July. Now, for the next chapter…

I’m going it alone.

I’ve spent over five years working on CSS Wizardry; writing articles, sharing techniques and code and research and findings, creating and contributing to open source projects, speaking at conferences and a whole lot more. Now I want to make all this stuff work for me. I want to take all the things I do – and have done – and do them for you, whoever and wherever you may be.

I want to work with talented teams – working on amazing products – all across the globe. I want to work with nice people who care as much about building great things as I do, and having fun in the process. I want people who take their work, but not themselves, seriously. I want to work with you.

Featured case study: NHS

How I helped the NHS rapidly build a brand new product.

Read case study…

I am going to become available from the end of October/mid-November so – regardless of your location, budget, requirements or whatever – if you think we could work together then let me know. We’ll see what we can work out.

My ideal clients – the ones who would benefit from me the most – are startups and products who have tech teams I can collaborate with. I specialise in scaling front-ends on products with skilled engineers. If you’re a startup expecting to grow, I can help that happen. If you’re a developer working on a product that needs someone to build a robust and scalable front-end, I’m your guy. If you’re an agency who needs help training your team to be able to build bigger websites for bigger clients, get in touch.

That said, I have no lists of what I can and cannot do, nor do I have lists of what I will and will not do, I’m open to pretty much anything. If you think your team or product or app or service or agency or startup could benefit from anything I could offer then just drop me a line. One of the most important things that I want to gain from this (ad)venture is variety. From consulting to dev work, workshops to speaking, I want to work on an array of things for nice people. I don’t mind what your product or project is, or what your budget may be, let’s chat it over and see what we can do together.

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!


  • inuitcss
  • ITCSS – coming soon…
  • CSS Guidelines

Next Appearance

  • Talk & Workshop

    WebExpo: Prague (Czech Republic), May 2024


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.