Tags: ba



Monday, May 20th, 2019

Web Bloat Score Calculator

Page web bloat score (WebBS for short) is calculated as follows:

WebBS = TotalPageSize / PageImageSize

Yes, this is a tongue-in-cheek somewhat arbitrary measurement, but it’s well worth reading through the rationale for it.

How can the image of a page be smaller than the page itself?

Sunday, May 19th, 2019


Checked in at British Airways Galleries Lounge. Homeward bound.

Wednesday, May 8th, 2019

CSS-only chat

A truly monstrous async web chat using no JS whatsoever on the frontend.

This is …I mean …yes, but …it …I …

Tuesday, May 7th, 2019

JavaScript pedalboard

Effects pedals in the browser, using the Web Audio API. Very cool!

Be sure to read Trys’s write-up too.

Sunday, April 28th, 2019

Norbert Wiener’s Human Use of Human Beings is more relevant than ever.

What would Wiener think of the current human use of human beings? He would be amazed by the power of computers and the internet. He would be happy that the early neural nets in which he played a role have spawned powerful deep-learning systems that exhibit the perceptual ability he demanded of them—although he might not be impressed that one of the most prominent examples of such computerized Gestalt is the ability to recognize photos of kittens on the World Wide Web.

Wednesday, April 24th, 2019

Untold History of AI - IEEE Spectrum

A terrific six-part series of short articles looking at the people behind the history of Artificial Intelligence, from Babbage to Turing to JCR Licklider.

  1. When Charles Babbage Played Chess With the Original Mechanical Turk
  2. Invisible Women Programmed America’s First Electronic Computer
  3. Why Alan Turing Wanted AI Agents to Make Mistakes
  4. The DARPA Dreamer Who Aimed for Cyborg Intelligence
  5. Algorithmic Bias Was Born in the 1980s
  6. How Amazon’s Mechanical Turkers Got Squeezed Inside the Machine

The history of AI is often told as the story of machines getting smarter over time. What’s lost is the human element in the narrative, how intelligent machines are designed, trained, and powered by human minds and bodies.

Thursday, April 18th, 2019

Inlining SVG background images in CSS with custom properties

Here’s a tiny lesson that I picked up from Trys that I’d like to share with you…

I was working on some upcoming changes to the Clearleft site recently. One particular component needed some SVG background images. I decided I’d inline the SVGs in the CSS to avoid extra network requests. It’s pretty straightforward:

.myComponent {
    background-image: url('data:image/svg+xml;utf8,<svg> ... </svg>');

You can basically paste your SVG in there, although you need to a little bit of URL encoding: I found that converting # to %23 to was enough for my needs.

But here’s the thing. My component had some variations. One of the variations had multiple background images. There was a second background image in addition to the first. There’s no way in CSS to add an additional background image without writing a whole background-image declaration:

.myComponent--variant {
    background-image: url('data:image/svg+xml;utf8,<svg> ... </svg>'), url('data:image/svg+xml;utf8,<svg> ... </svg>');

So now I’ve got the same SVG source inlined in two places. That negates any performance benefits I was getting from inlining in the first place.

That’s where Trys comes in. He shared a nifty technique he uses in this exact situation: put the SVG source into a custom property!

:root {
    --firstSVG: url('data:image/svg+xml;utf8,<svg> ... </svg>');
    --secondSVG: url('data:image/svg+xml;utf8,<svg> ... </svg>');

Then you can reference those in your background-image declarations:

.myComponent {
    background-image: var(--firstSVG);
.myComponent--variant {
    background-image: var(--firstSVG), var(--secondSVG);

Brilliant! Not only does this remove any duplication of the SVG source, it also makes your CSS nice and readable: no more big blobs of SVG source code in the middle of your style sheet.

You might be wondering what will happen in older browsers that don’t support CSS custom properties (that would be Internet Explorer 11). Those browsers won’t get any background image. Which is fine. It’s a background image. Therefore it’s decoration. If it were an important image, it wouldn’t be in the background.

Progressive enhancement, innit?

Saturday, April 13th, 2019

Checked in at The Parlour. Afternoon tea — with Jessica map

Checked in at The Parlour. Afternoon tea — with Jessica

Offline fallback page with service worker - Modern Web Development: Tales of a Developer Advocate by Paul Kinlan

Paul describes a fairly straightforward service worker recipe: a custom offline page for failed requests.

Sergey | the little SSG

Trys has made YASSG—Yet Another Static Site Generator. It’s called Sergey (like SSG, see?) and it does just one thing: it allows you to include chunks of markup. It’s Apache Server Side Includes all over again!

Kick the tyres and see what you think.

Monday, April 8th, 2019

AddyOsmani.com - Native image lazy-loading for the web!

The loading attribute for images and iframes is coming to Chrome. The best part:

You can also use loading as a progressive enhancement. Browsers that support the attribute can get the new lazy-loading behavior with loading=lazy and those that don’t will still have images load.

Break out of the echo chamber - Andy Bell

So much of my echo chamber is consumed by people, including myself, who have a very dim view of JavaScript frameworks being thrown at everything, arguing with the people who are in the process of throwing JavaScript frameworks at everything. We forget one very important thing, though: we represent the minority of the web community and our arguments probably look very pointless and silly to the majority.

Sunday, April 7th, 2019

Drag’n’drop revisited

I got a message from a screen-reader user of The Session recently, letting me know of a problem they were having. I love getting any kind of feedback around accessibility, so this was like gold dust to me.

They pointed out that the drag’n’drop interface for rearranging the order of tunes in a set was inaccessible.

Drag and drop

Of course! I slapped my forehead. How could I have missed this?

It had been a while since I had implemented that functionality, so before even looking at the existing code, I started to think about how I could improve the situation. Maybe I could capture keystroke events from the arrow keys and announce changes via ARIA values? That sounded a bit heavy-handed though: mess with people’s native keyboard functionality at your peril.

Then I looked at the code. That was when I realised that the fix was going to be much, much easier than I thought.

I documented my process of adding the drag’n’drop functionality back in 2016. Past me had his progressive enhancement hat on:

One of the interfaces needed for this feature was a form to re-order items in a list. So I thought to myself, “what’s the simplest technology to enable this functionality?” I came up with a series of select elements within a form.


The problem was in my feature detection:

There’s a little bit of mustard-cutting going on: does the dragula object exist, and does the browser understand querySelector? If so, the select elements are hidden and the drag’n’drop is enabled.

The logic was fine, but the execution was flawed. I was being lazy and hiding the select elements with display: none. That hides them visually, but it also hides them from screen readers. I swapped out that style declaration for one that visually hides the elements, but keeps them accessible and focusable.

It was a very quick fix. I had the odd sensation of wanting to thank Past Me for making things easy for Present Me. But I don’t want to talk about time travel because if we start talking about it then we’re going to be here all day talking about it, making diagrams with straws.

I pushed the fix, told the screen-reader user who originally contacted me, and got a reply back saying that everything was working great now. Success!

Friday, March 29th, 2019

City life | Trys Mudford

Not only does the differentiation of terms create a divide within the industry, the term ‘web app’ regularly acts as an excuse for corner cutting and the exclusion of users.

Straight-talkin’ Trys:

We kid ourselves into thinking we’re building groundbreakingly complex systems that require bleeding-edge tools, but in reality, much of what we build is a way to render two things: a list, and a single item. Here are some users, here is a user. Here are your contacts, here are your messages with that contact. There ain’t much more to it than that.

Monday, March 25th, 2019

Stuffing the Front End

53% of mobile visits leave a page that takes longer than 3 seconds to load. That means that a large number of visitors probably abandoned these sites because they were staring at a blank screen for 3 seconds, said “fuck it,” and left approximately half way before the page showed up. The fact that the next page interaction would have been quicker—assuming all the JS files even downloaded correctly in the first attempt—doesn’t amount to much if they didn’t stick around for the first page to load. What was gained by putting the business logic in the front end in this scenario?

Wednesday, March 20th, 2019

Competing by mimicking - Andy Bell

In my mind, the only way to “compete” with native apps is to do better than native apps—and with the web platform consistently improving and enabling us to produce app-like experiences, with Service Workers, ES6+ JavaScript, modern CSS and Web Components: we are very much on the path to do better than native apps.

Tuesday, March 12th, 2019

Checked in at Science Museum. Second stop on the #web30 tour — with Remy map

Checked in at Science Museum. Second stop on the #web30 tour — with Remy

Saturday, March 9th, 2019

Performance Budgets That Stick - TimKadlec.com

I like Tim’s definition here:

A performance budget is a clearly defined limit on one or more performance metrics that the team agrees not to exceed, and that is used to guide design and development.

And I agree about the four attributes required for a performance budget to succeed. It must be:

  1. Concrete
  2. Meaningful
  3. Integrated
  4. Enforceable

The point is not to let the performance budget try to stand on its own, somewhere hidden in company documentation collecting dust. You need to be proactive about making the budget become a part of your everyday work.

Thursday, March 7th, 2019

Sparkline Sound-Off – Chris Burnell

Chris has made sonic sparklines on his site too, but they’re far more musical than mine. Here’s his explanation of how he did it.