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Simon Hearne

WebPerf, 3D Printing, Coffee and Data Science

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Twitter Lite isn't as good as the app, and that's okay

Twitter's Progressive Web App is finally out of testing, and it's not as good as the native app. Missing push notifications, wonky images, small text boxes, ...

Your Analytics Lies to You

You can't rely on your web analytics for performance data and it's understating bounce rate and traffic numbers from old devices.

How to Optimise CSS Image Sprites

Optimising sprites might be more important than you think, and easier than you expect!


Three WebPerf Takeaways from Velocity Europe

Velocity Amsterdam has just come to a close. Here are the three key things that I am taking away from the two days of sessions.

Velocity NY 2016 - Wrap-up

Velocity New York seems like a distant memory now, especially with Velocity Europe around the corner. With that said, I have copious notes from the two day c...

Blocking requests in webpagetest? Don't use Chrome.

We know that third-party content can harm the user experience on a website. Measuring that impact can be tricky.

How fast is fast enough?

Do you know when your website’s speed starts to impact your customers’ behaviour?

Getting Reliable Visual Performance Metrics

Visual metrics such as Speed Index, render start and visual complete are the best proxies we have for user experience. Unfortunately two of these are totally...

Render Conf 2016

Render Conference - previously known as jQuery UK - was held in Oxford last week. It's a front-end conference for front-end people, which makes me a bit of a...

Prioritising Site Speed Recommendations

Sometimes prioritising recommendations is more important than making them.


Velocity Europe 2015 - The Good Ones!

This post is a review and summary of the talks at Velocity Europe that I attended. I've summarised each talk and given links to the slides, videos and rating...

Velocity Europe 2015 - My Allstars

This post is a review and summary of the talks at Velocity Europe that got a 5 star review from me. I've summarised each talk and given links to the slides, ...

Measuring Webpage Jank

Webpage jank can harm the user experience, here's an easy way to measure it on your pages

Be Mindful With Modernizr

Modernizr might be making your site slow, especially on mobiles

The Future of Web Performance - Part 1

Web performance is critically important, how will upcoming technologies change the way we manage it?

Questions to Ask Your Third-Parties

We need rules to keep third-party Javascript in check.

Manage Third-party Risk Using a Content Security Policy

A feature to prevent cross-site-scripting may make it easier to police third-party javascript.

Using a Web Performance Heatmap to Assess Page Performance

I've made a Heatmap to visualise when each element loads on a page.

How to Find the Third-Parties on Your Site

Third party means not you or me, but them.

Web Performance Optimisation Basics

Website performance is critical to user experience. We need rules to make it easier.