Archive: September, 2018

I gave a talk at the State Of The Browser conference in London earlier this month. It was a 25 minute spiel called The Web Is Agreement.

While I was putting the talk together, I posted some pictures of my talk preparation process. People seemed to be quite interested in that peek behind the curtain, so I thought I’d jot down the process I used.

There are two aspects to preparing a talk: the content and the presentation. I like to keep the preparation of those two parts separate. It’s kind of like writing: instead of writing and editing at the same time, it’s more productive to write any old crap first (to get it out of your head) and then go back and edit—“write drunk and edit sober”. Separating out those two mindsets allows you to concentrate on the task at hand.

So, to begin with, I’m not thinking about how I’m going to present the material at all. I’m only concerned with what I want to say.

When it comes to preparing the subject matter for a talk, step number zero is to banish your inner critic. You know who I mean. That little asshole with the sneering voice that says things like “you’re not qualified to talk about this” or “everything has already been said.” Find a way to realise that this demon is a) speaking from inside your head and b) not real. Maybe try drawing your inner critic. Ridiculous? Yes. Yes, it is.

Alright, time to start. There’s nothing more intimidating than a blank slidedeck, except maybe a blank Photoshop file, or a blank word processing document. In each of those cases, I find that starting with software is rarely a good idea. Paper is your friend.

I get a piece of A3 paper and start scribbling out a mind map. “Mind map” is a somewhat grandiose term for what is effectively a lo-fi crazy wall.

The idea here is to get everything out of my head. Don’t self-censor. At this stage, there are no bad ideas. This is a “yes, and…” exercise, not a “no, but…” exercise. Divergent, not convergent.

Not everything will make it into the final talk. That’s okay. In fact, I often find that there’s one thing that I’m really attached to, that I’m certain will be in the talk, that doesn’t make the cut. Kill your darlings.

I used to do this mind-mapping step by opening a text file and dumping my thoughts into it. I told myself that they were in no particular order, but because a text file reads left to right and top to bottom, they are in an order, whether I intended it or not. By using a big sheet of paper, I can genuinely get things down in a disconnected way (and later, I can literally start drawing connections).

For this particular talk, I knew that the subject matter would be something to do with web standards. I brain-dumped every vague thought I had about standards in general.

The next step is what I call chunking. I start to group related ideas together. Then I give a label to each of these chunks. Personally, I like to use a post-it note per chunk. I put one word or phrase on the post-it note, but it could just as easily be a doodle. The important thing is that you know what the word or doodle represents. Each chunk should represent a self-contained little topic that you might talk about for 3 to 5 minutes.

At this point, I can start thinking about the structure of the talk: “Should I start with this topic? Or should I put that in the middle?” The cost of changing my mind is minimal—I’m just moving post-it notes around.

With topics broken down into chunks like this, I can flesh out each one. The nice thing about this is that I’ve taken one big overwhelming task—prepare a presentation!—and I’ve broken it down into smaller, more manageable tasks. I can take a random post-it note and set myself, say, ten or fifteen minutes to jot down an explanation of it.

The explanation could just be bullet points. For this particular talk, I decided to write full sentences.

Even though, in this case, I was writing out my thoughts word for word, I still kept the topics in separate files. That way, I can still move things around easily.

Crafting the narrative structure of a talk is the part I find most challenging …but it’s also the most rewarding. By having the content chunked up like this, I can experiment with different structures. I like to try out different narrative techniques from books and films, like say, flashback: find the most exciting part of the talk; start with that, and then give the backstory that led up to it. That’s just one example. There are many possible narrative stuctures.

What I definitely don’t do is enact the advice that everyone is given for their college presentations:

1. say what you’re going to say,
2. say it, and
3. recap what you’ve said.

To me, that’s the equivalent of showing an audience the trailer for a film right before watching the film …and then reading a review of the film right after watching it. Just play the film! Give the audience some credit—assume the audience has no knowledge but infinite intelligence.

Oh, and there’s one easy solution to cracking the narrative problem: make a list. If you’ve got 7 chunks, you can always give a talk on “Seven things about whatever” …but it’s a bit of a cop-out. I mean, most films have a three-act structure, but they don’t start the film by telling the audience that, and they don’t point out when one act finishes and another begins. I think it’s much more satisfying—albeit more challenging—to find a way to segue from chunk to chunk.

Finding the narrative thread is tricky work, but at least, by this point, it’s its own separate task: if I had tried to figure out the narrative thread at the start of the process, or even when I was chunking things out, it would’ve been overwhelming. Now it’s just the next task in my to-do list.

I suppose, at this point, I might as well make some slides.

I’m not trying to be dismissive of slides—I think having nice slides is a very good thing. But I do think that they can become the “busy work” of preparing a presentation. If I start on the slides too soon, I find they’ll take up all my time. I think it’s far more important to devote time to the content and structure of the talk. The slides should illustrate the talk …but the slides are not the talk.

If you don’t think of the slides as being subservient to the talk, there’s a danger that you’ll end up with a slidedeck that’s more for the speaker’s benefit than the audience’s.

It’s all too easy to use the slides as a defence mechanism. You’re in a room full of people looking towards you. It’s perfectly reasonable for your brain to scream, “Don’t look at me! Look at the slides!” But taken too far, that can be interpreted as “Don’t listen to me!”

For this particular talk, there were moments when I wanted to make sure the audience was focused on some key point I was making. I decided that having no slide at all was the best way of driving home my point.

But slidedeck style is quite a personal thing, so use whatever works for you.

It’s a similar story with presentation style. Apart from some general good advice—like, speak clearly—the way you present should be as unique as you are. I have just one piece of advice, and it’s this: read Demystifying Public Speaking by Lara Hogan—it’s really, really good!

(I had to apologise to Lara last time I saw her, because I really wanted her to sign my copy of her book …but I didn’t have it, because it’s easily the book I’ve loaned out to other people the most.)

I did a good few run-throughs of my talk. There were a few sentences that sounded fine written down, but were really clumsy to say out loud. It reminded me of what Harrison Ford told George Lucas during the filming of Star Wars: “You can type this shit, George, but you can’t say it.”

I gave a final run-through at work to some of my Clearleft colleagues. To be honest, I find that more nerve-wracking than speaking on a stage in front of a big room full of strangers. I think it’s something to do with the presentation of self.

Finally, the day of the conference rolled around, and I was feeling pretty comfortable with my material. I’m pretty happy with how it turned out. You can read The Web Is Agreement, and you can look at the slides, but as with any conference talk, you kinda had to be there.

I was getting reports of some odd behaviour with the service worker on thesession.org, the Irish music website I run. Someone emailed me to say that they kept getting the offline page, even when their internet connection was perfectly fine and the site was up and running.

They didn’t mind answering my pestering follow-on questions to isolate the problem. They told me that they were using the Samsung Internet browser on Android. After a little searching, I found this message on a Github thread about using waitUntil. It’s from someone who works on the Samsung Internet team:

Sadly, the asynchronos waitUntil() is not implemented yet in our browser. Yes, we will implement it but our release cycle is so far. So, for a long time, we might not resolve the issue.

A-ha! That explains the problem. See, here’s the pattern I was using:

1. When someone requests a file,
2. fetch that file from the network,
3. create a copy of the file and cache it,
4. return the contents.

Step 1 is the event listener:

// 1. When someone requests a file
addEventListener('fetch', fetchEvent => {
  let request = fetchEvent.request;
  fetchEvent.respondWith(

Steps 2, 3, and 4 are inside that respondWith:

// 2. fetch that file from the network
fetch(request)
.then( responseFromFetch => {
  // 3. create a copy of the file and cache it
  let copy = responseFromFetch.clone();
  caches.open(cacheName)
  .then( cache => {
    cache.put(request, copy);
  })
  // 4. return the contents.
  return responseFromFetch;
})

Step 4 might well complete while step 3 is still running (remember, everything in a service worker script is asynchronous so even though I’ve written out the steps sequentially, you never know what order the steps will finish in). That’s why I’m wrapping that third step inside fetchEvent.waitUntil:

// 2. fetch that file from the network
fetch(request)
.then( responseFromFetch => {
  // 3. create a copy of the file and cache it
  let copy = responseFromFetch.clone();
  fetchEvent.waitUntil(
    caches.open(cacheName)
    .then( cache => {
      cache.put(request, copy);
    })
  );
  // 4. return the contents.
  return responseFromFetch;
})

If a browser (like Samsung Internet) doesn’t understand the bit where I say fetchEvent.waitUntil, then it will throw an error and execute the catch clause. That’s where I have my fifth and final step: “try looking in the cache instead, but if that fails, show the offline page”:

.catch( fetchError => {
  console.log(fetchError);
  return caches.match(request)
  .then( responseFromCache => {
    return responseFromCache || caches.match('/offline');
  });
})

Normally in this kind of situation, I’d use feature detection to check whether a browser understands a particular API method. But it’s a bit tricky to test for support for asynchronous waitUntil. That’s okay. I can use a try/catch statement instead. Here’s what my revised code looks like:

fetch(request)
.then( responseFromFetch => {
  let copy = responseFromFetch.clone();
  try {
    fetchEvent.waitUntil(
      caches.open(cacheName)
      .then( cache => {
        cache.put(request, copy);
      })
    );
  } catch (error) {
    console.log(error);
  }
  return responseFromFetch;
})

Now I’ve managed to localise the error. If a browser doesn’t understand the bit where I say fetchEvent.waitUntil, it will execute the code in the catch clause, and then carry on as usual. (I realise it’s a bit confusing that there are two different kinds of catch clauses going on here: on the outside there’s a .then()/.catch() combination; inside is a try{}/catch{} combination.)

At some point, when support for async waitUntil statements is universal, this precautionary measure won’t be needed, but for now wrapping them inside try doesn’t do any harm.

There are a few places in chapter five of Going Offline—the chapter about service worker strategies—where I show examples using async waitUntil. There’s nothing wrong with the code in those examples, but if you want to play it safe (especially while Samsung Internet doesn’t support async waitUntil), feel free to wrap those examples in try/catch statements. But I’m not going to make those changes part of the errata for the book. In this case, the issue isn’t with the code itself, but with browser support.

Here at Clearleft, we’ve recently been doing some front-end consultancy. That prompted me to jot down thoughts on design principles and performance:

• Robustness and least power
• The top four web performance challenges

We continued with some more performance work this week. Having already covered some of the nitty-gritty performance tactics like font-loading, image optimisation, etc., we wanted to take a step back and formulate an ongoing strategy for performance.

When it comes to web performance, the eternal question is “What should we measure?” The answer to that question will determine where you then concentrate your efforts—whatever it is your measuring, that’s what you’ll be looking to improve.

I started by drawing a distinction between measurements of quantities and measurements of time. Quantities are quite easy to measure. You can measure these quantities using nothing more than browser dev tools:

• overall file size (page weight + assets), and
• number of requests.

I think it’s good to measure these quantities, and I think it’s good to have a performance budget for them. But I also think they’re table stakes. They don’t actually tell you much about the impact that performance is having on the user experience. For that, we need to enumerate moments in time:

• time to first byte,
• time to first render,
• time to first meaningful paint, and
• time to first meaningful interaction.

There’s one more moment in time, which is the time until DOM content is loaded. But I’m not sure that has a direct effect on how performance is perceived, so it feels like it belongs more in the category of quantities than time.

Next, we listed out all the factors that could affect each of the moments in time. For example, the time to first byte depends on the speed of the network that the user is on. It also depends on how speedily your server (or Content Delivery Network) can return a response. Meanwhile, time to first render is affected by the speed of the user’s network, but it’s also affected by how many blocking elements are on the critical path.

By listing all the factors out, we can draw a distinction between the factors that are outside of our control, and the factors that we can do something about. So while we might not be able to do anything about the speed of the user’s network, we might well be able to optimise the speed at which our server returns a response, or we might be able to defer some assets that are currently blocking the critical path.

	Factors
1st byte	server speed network speed
1st render	network speed critical path assets
1st meaningful paint	network speed font-loading strategy image optimisation
1st meaningful interaction	network speed device processing power JavaScript size

So far, everything in our list of performance-affecting factors is related to the first visit. It’s worth drawing up a second list to document all the factors for subsequent visits. This will look the same as the list for first visits, but with the crucial difference that caching now becomes a factor.

	First visit factors	Repeat visit factors
1st byte	server speed network speed	server speed network speed caching
1st render	network speed critical path assets	network speed critical path assets caching
1st meaningful paint	network speed font-loading strategy image optimisation	network speed font-loading strategy image optimisation caching
1st meaningful interaction	network speed device processing power JavaScript size	network speed device processing power JavaScript size caching

Alright. Now it’s time to get some numbers for each of the four moments in time. I use Web Page Test for this. Choose a realistic setting, like 3G on an Android from the East coast of the USA. Under advanced settings, be sure to select “First View and Repeat View” so that you can put those numbers in two different columns.

Here are some numbers for adactio.com:

	First visit time	Repeat visit time
1st byte	1.476 seconds	1.215 seconds
1st render	2.633 seconds	1.930 seconds
1st meaningful paint	2.633 seconds	1.930 seconds
1st meaningful interaction	2.868 seconds	2.083 seconds

I’m getting the same numbers for first render as first meaningful paint. That tells me that there’s no point in trying to optimise my font-loading, for example …which makes total sense, because adactio.com isn’t using any web fonts. But on a different site, you might see a big gap between those numbers.

I am seeing a gap between time to first byte and time to first render. That tells me that I might be able to get some blocking requests off the critical path. Sure enough, I’m currently referencing an external stylesheet in the head of adactio.com—if I were to inline critical styles and defer the loading of that stylesheet, I should be able to narrow that gap.

A straightforward site like adactio.com isn’t going to have much to worry about when it comes to the time to first meaningful interaction, but on other sites, this can be a significant bottleneck. If you’re sending UI elements in the initial HTML, but then waiting for JavaScript to “hydrate” those elements into working, the user can end up in an uncanny valley of tapping on page elements that look fine, but aren’t ready yet.

My point is, you’re going to see very different distributions of numbers depending on the kind of site you’re testing. There’s no one-size-fits-all metric to focus on.

Now that you’ve got numbers for how your site is currently performing, you can create two new columns: one of those is a list of first-visit targets, the other is a list of repeat-visit targets for each moment in time. Try to keep them realistic.

For example, if I could reduce the time to first render on adactio.com by 0.5 seconds, my goals would look like this:

	First visit goal	Repeat visit goal
1st byte	1.476 seconds	1.215 seconds
1st render	2.133 seconds	1.430 seconds
1st meaningful paint	2.133 seconds	1.430 seconds
1st meaningful interaction	2.368 seconds	1.583 seconds

See how the 0.5 seconds saving cascades down into the other numbers?

Alright! Now I’ve got something to aim for. It might also be worth having an extra column to record which of the moments in time are high priority, which are medium priority, and which are low priority.

	Priority
1st byte	Medium
1st render	High
1st meaningful paint	Low
1st meaningful interaction	Low

Your goals and priorities may be quite different.

I think this is a fairly useful framework for figuring out where to focus when it comes to web performance. If you’d like to give it a go, I’ve made a web performance chart for you to print out and fill in. Here’s a PDF version if that’s easier for printing. Or you can download the HTML version if you want to edit it.

I have to say, I’m really enjoying the front-end consultancy work we’ve been doing at Clearleft around performance and related technologies, like offline functionality. I’d like to do more of it. If you’d like some help in prioritising performance at your company, please get in touch. Let’s make the web faster together.

Anne Gibson writes:

It sounds easy to make writing a habit, but like every other habit that doesn’t involve addictive substances like nicotine or dopamine it’s hard to start and easy to quit.

Alice Bartlett writes:

Anyway, here we are, on my blog, or in your RSS reader. I think I’ll do weaknotes. Some collections of notes. Sometimes. Not very well written probably. Generally written with the urgency of someone who is waiting for a baby wake up.

Patrick Rhone writes:

Bottom line; please place any idea worth more than 280 characters and the value Twitter places on them (which is zero) on a blog that you own and/or can easily take your important/valuable/life-changing ideas with you and make them easy for others to read and share.

Sara Soueidan writes:

What you write might help someone understand a concept that you may think has been covered enough before. We each have our own unique perspectives and writing styles. One writing style might be more approachable to some, and can therefore help and benefit a large (or even small) number of people in ways you might not expect.

Just write.

Even if only one person learns something from your article, you’ll feel great, and that you’ve contributed — even if just a little bit — to this amazing community that we’re all constantly learning from. And if no one reads your article, then that’s also okay. That voice telling you that people are just sitting somewhere watching our every step and judging us based on the popularity of our writing is a big fat pathetic attention-needing liar.

Laura Kalbag writes:

The web can be used to find common connections with folks you find interesting, and who don’t make you feel like so much of a weirdo. It’d be nice to be able to do this in a safe space that is not being surveilled.

Owning your own content, and publishing to a space you own can break through some of these barriers. Sharing your own weird scraps on your own site makes you easier to find by like-minded folks.

Brendan Dawes writes:

At times I think “will anyone reads this, does anyone care?”, but I always publish it anyway — and that’s for two reasons. First it’s a place for me to find stuff I may have forgotten how to do. Secondly, whilst some of this stuff is seemingly super-niche, if one person finds it helpful out there on the web, then that’s good enough for me. After all I’ve lost count of how many times I’ve read similar posts that have helped me out.

Robin Rendle writes:

My advice after learning from so many helpful people this weekend is this: if you’re thinking of writing something that explains a weird thing you struggled with on the Internet, do it! Don’t worry about the views and likes and Internet hugs. If you’ve struggled with figuring out this thing then be sure to jot it down, even if it’s unedited and it uses too many commas and you don’t like the tone of it.

Khoi Vinh writes:

Maybe you feel more comfortable writing in short, concise bullets than at protracted, grandiose length. Or maybe you feel more at ease with sarcasm and dry wit than with sober, exhaustive argumentation. Or perhaps you prefer to knock out a solitary first draft and never look back rather than polishing and tweaking endlessly. Whatever the approach, if you can do the work to find a genuine passion for writing, what a powerful tool you’ll have.

Amber Wilson writes:

I want to finally begin writing about psychology. A friend of mine shared his opinion that writing about this is probably best left to experts. I tried to tell him I think that people should write about whatever they want. He argued that whatever he could write about psychology has probably already been written about a thousand times. I told him that I’m going to be writer number 1001, and I’m going to write something great that nobody has written before.

Austin Kleon writes:

Maybe I’m weird, but it just feels good. It feels good to reclaim my turf. It feels good to have a spot to think out loud in public where people aren’t spitting and shitting all over the place.

Tim Kadlec writes:

I write to understand and remember. Sometimes that will be interesting to others, often it won’t be.

But it’s going to happen. Here, on my own site.

You write…

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.

I’m clueless when it comes to React, but I really enjoy getting down to the nitty-gritty of browser features—HTML, CSS, and JavaScript APIs. Our skillsets complement one another nicely.

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?

3. Images

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.

2. Our JavaScript

Just missing out on making the top spot is the JavaScript that we send down the pipe to our long-suffering users. There’s nothing wrong with the code itself—I’m sure it’s very good. There’s just too damn much of it. And that’s a real performance bottleneck, especially on mobile.

So stop sending so much JavaScript—a solution as simple as Monty Python’s instructions for playing the flute.

1. Other people’s JavaScript

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.

It’s so disheartening when you’ve devoted your time and energy into your web font loading strategy, and optimising your images, and unbundling your JavaScript …only to have someone else’s JavaScript just shit all over your nice performance budget.

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:

No external JavaScript is allowed in an AMP HTML document. This covers third-party libraries, advertising and tracking scripts. This is A-okay with me.

The reasons given for this ban are related to performance and I agree with them completely. Big bloated JavaScript libraries are one of the biggest performance killers on the web.

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.

Unless…

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.

There is power in a union.

There’s a great article by Steven Garrity over on A List Apart called Design with Difficult Data. It runs through the advantages of using unusual content to stress-test interfaces, referencing Postel’s Law, AKA the robustness principle:

Be conservative in what you send, be liberal in what you accept.

Even though the robustness principle was formulated for packet-switching, I see it at work in all sorts of disciplines, including design. A good example is in best practices for designing forms:

Every field you ask users to fill out requires some effort. The more effort is needed to fill out a form, the less likely users will complete the form. That’s why the foundational rule of form design is shorter is better — get rid of all inessential fields.

In other words, be conservative in the number of form fields you send to users. But then, when it comes to users filling in those fields:

It’s very common for a few variations of an answer to a question to be possible; for example, when a form asks users to provide information about their state, and a user responds by typing their state’s abbreviation instead of the full name (for example, CA instead of California). The form should accept both formats, and it’s the developer job to convert the data into a consistent format.

In other words, be liberal in what you accept from users.

I find the robustness principle to be an immensely powerful way of figuring out how to approach many design problems. When it comes to figuring out what specific tools or technologies to use, there’s an equally useful principle: the rule of least power:

Choose the least powerful language suitable for a given purpose.

On the face of it, this sounds counter-intuitive; why forego a powerful technology in favour of something less powerful?

Well, power comes with a price. Powerful technologies tend to be more complex, which means they can be trickier to use and trickier to swap out later.

Take the front-end stack, for example: HTML, CSS, and JavaScript. HTML and CSS are declarative, so you don’t get as much precise control as you get with an imperative language like JavaScript. But JavaScript comes with a steeper learning curve and a stricter error-handling model than HTML or CSS.

As a general rule, it’s always worth asking if you can accomplish something with a less powerful technology:

In the web front-end stack — HTML, CSS, JS, and ARIA — if you can solve a problem with a simpler solution lower in the stack, you should. It’s less fragile, more foolproof, and just works.

• Instead of using JavaScript to do animation, see if you can do it in CSS instead.
• Instead of using JavaScript to do simple client-side form validation, try to use HTML input types and attributes like required.
• Instead of using ARIA to give a certain role value to a div or span, try to use a more suitable HTML element instead.

It sounds a lot like the KISS principle: Keep It Simple, Stupid. But whereas the KISS principle can be applied within a specific technology—like keeping your CSS manageable—the rule of least power is all about evaluating technology; choosing the most appropriate technology for the task at hand.

There are some associated principles, like YAGNI: You Ain’t Gonna Need It. That helps you avoid picking a technology that’s too powerful for your current needs, but which might be suitable in the future: premature optimisation. Or, as Rachel put it, stop solving problems you don’t yet have:

So make sure every bit of code added to your project is there for a reason you can explain, not just because it is part of some standard toolkit or boilerplate.

There’s no shortage of principles, laws, and rules out there, and I find many of them very useful, but if I had to pick just two that are particularly applicable to my work, they would be the robustness principle and the rule of least of power.

After all, if they’re good enough for Tim Berners-Lee…

I finally got around to reading Sapiens by Yuval Noah Harari. It’s one of those books that I kept hearing about from smart people whose opinions I respect. But I have to say, my reaction to the book reminded me of when I read Matt Ridley’s The Rational Optimist:

It was an exasperating read.

At first, I found the book to be a rollicking good read. It told the sweep of history in an engaging way, backed up with footnotes and references to prime sources. But then the author transitions from relaying facts to taking flights of fancy without making any distinction between the two (the only “tell” is that the references dry up).

Just as Matt Ridley had personal bugbears that interrupted the flow of The Rational Optimist, Yuval Noah Harari has fixated on some ideas that make a mess of the narrative arc of Sapiens. In particular, he believes that the agricultural revolution was, as he describes it, “history’s biggest fraud.” In the absence of any recorded evidence for this, he instead provides idyllic descriptions of the hunter-gatherer lifestyle that have as much foundation in reality as the paleo diet.

When the book avoids that particular historical conspiracy theory, it fares better. But even then, the author seems to think he’s providing genuinely new insights into matters of religion, economics, and purpose, when in fact, he’s repeating the kind of “college thoughts” that have been voiced by anyone who’s ever smoked a spliff.

I know I’m making it sound terrible, and it’s not terrible. It’s just …generally not that great. And when it is great, it only makes the other parts all the more frustrating. There’s a really good book in Sapiens, but unfortunately it’s interspersed with some pretty bad editorialising. I have to agree with Galen Strawson’s review:

Much of Sapiens is extremely interesting, and it is often well expressed. As one reads on, however, the attractive features of the book are overwhelmed by carelessness, exaggeration and sensationalism.

Towards the end of Sapiens, Yuval Noah Harari casts his eye on our present-day world and starts to speculate on the future. This is the point when I almost gave myself an injury with the amount of eye-rolling I was doing. His ideas on technology, computers, and even science fiction are embarrassingly childish and incomplete. And the bad news is that his subsequent books—Home Deus and 21 Lessons For The 21st Century—are entirely speculations about humanity and technology. I won’t be touching those with all the ten foot barge poles in the world.

In short, although there is much to enjoy in Sapiens, particularly in the first few chapters, I can’t recommend it.

If you’re looking for a really good book on the fascinating history of our species, read A Brief History of Everyone Who Ever Lived by Adam Rutherford . That’s one I can recommend without reservation.