The top four web performance challenges
Danielle and I have been doing some front-end consultancy for a local client recently.
We’ve both been enjoying it a lot—it’s exhausting but rewarding work. So if you’d like us to come in and spend a few days with your company’s dev team, please get in touch.
I’ve certainly enjoyed the opportunity to watch Danielle in action, leading a workshop on refactoring React components in a pattern library. She’s incredibly knowledgable in that area.
This recent work was what prompted my thoughts around the principles of robustness and least power. We spent a day evaluating a continuum of related front-end concerns: semantics, accessibility, performance, and SEO.
When it came to performance, a lot of the work was around figuring out the most suitable metric to prioritise:
- time to first byte,
- time to first render,
- time to first meaningful paint, or
- time to first meaningful interaction.
And that doesn’t even cover the more easily-measurable numbers like:
- overall file size,
- number of requests, or
- pagespeed insights score.
One outcome was to realise that there’s a tendency (in performance, accessibility, or SEO) to focus on what’s easily measureable, not because it’s necessarily what matters, but precisely because it is easy to measure.
Then we got down to some nuts’n’bolts technology decisions. I took a step back and looked at the state of performance across the web. I thought it would be fun to rank the most troublesome technologies in order of tricksiness. I came up with a top four list.
Here we go, counting down from four to the number one spot…
4. Web fonts
Coming in at number four, it’s web fonts. Sometimes it’s the combined weight of multiple font files that’s the problem, but more often that not, it’s the perceived performance that suffers (mostly because of when the web fonts appear).
Fortunately there’s a straightforward question to ask in this situation: WWZD—What Would Zach Do?
At the number three spot, it’s images. There are more of them and they just seem to be getting bigger all the time. And yet, we have more tools at our disposal than ever—better file formats, and excellent browser support for responsive images. Heck, we’re even getting the ability to lazy load images in HTML now.
So, as with web fonts, it feels like the impact of images on performance can be handled, as long as you give them some time and attention.
At number one with a bullet, it’s all the crap that someone else tells us to put on our websites. Analytics. Ads. Trackers. Beacons. “It’s just one little script”, they say. And then that one little script calls in another, and another, and another.
Here’s the really annoying thing: when I go to performance conferences, or participate in performance discussions, you know who’s nowhere to be found? The people making those third-party scripts.
The narrative around front-end performance is that it’s up to us developers to take responsibility for how our websites perform. But by far the biggest performance impact comes from third-party scripts.
There is a solution to this, but it’s not a technical one. We could refuse to add overweight (and in many cases, unethical) third-party scripts to the sites we build.
I have many, many issues with Google’s AMP project, but I completely acknowledge that it solves a political problem:
But how can we take that lesson from AMP and apply it to all our web pages? If we simply refuse to be the one to add those third-party scripts, we get fired, and somebody else comes in who is willing to poison web pages with third-party scripts. There’s nothing to stop companies doing that.
Suppose we were to all make a pact that we would stand in solidarity with any of our fellow developers in that sort of situation. A sort of joining-together. A union, if you will.
There is power in a factory, power in the land, power in the hands of the worker, but it all amounts to nothing if together we don’t stand.