Open Turds

I’ve open-sourced a lot of pretty shit code.

So whenever somebody says “I’m not open-sourcing this because the code is shit”, I think: wow, it must be spectacularly bad.

And that only makes me want to see it more.

Automattic Shakeup

My employer Automattic‘s having a bit of a reorganisation. For unrelated reasons, this coincides with my superteam having a bit of a reorganisation, too, and I’m going to be on a different team next week than I’ve been on for most of the 4+ years I’ve been there1. Together, these factors mean that I have even less idea than usual what I do for a living, right now.

Dan, wearing an Oxford-branded t-shirt, shrugs and looks confused in front of a screen showing Automattic's "Work With Us" page.
What is it I do here again? Something something code WooCommerce something something marketplace awesome something, right?

On the whole, I approve of Matt‘s vision for this reorganisation. He writes:

Each [Automattic employee] gets a card: Be the Host, Help the Host, or Neutral.

You cannot change cards during the course of your day or week. If you do not feel aligned with your card, you need to change divisions within Automattic.

“Be the Host” folks are all about making Automattic’s web hosting offerings the best they possibly can be. These are the teams behind WordPress.com, VIP, and Tumblr, for example. They’re making us competitive on the global stage. They bring Automattic money in a very direct way, by making our (world class) hosting services available to our customers.

“Help the Host” folks (like me) are in roles that are committed to providing the best tools that can be used anywhere. You might run your copy of Woo, Jetpack, or (the client-side bit of) Akismet on Automattic infrastructure… or alternatively you might be hosted by one of our competitors or even on your own hardware. What we bring to Automattic is more ethereal: we keep the best talent and expertise in these technologies close to home, but we’re agnostic about who makes money out of what we create.

A laptop computer on a desk, showing a WordPress wp-admin page.
This stock photo confuses me so much that I had to use it. It’s WordPress, as seen in Chrome on Windows Vista… but running on a MacBook Air. The photographer has tried to blur their site domain name (but it’s perfectly readable), but hasn’t concealed the fact they’re running µTorrent in the background (for Obviously Legal Reasons, I’m sure). Weird. But the important thing is that, crazy as this person’s choices are, they can use Automattic’s software however they like. It’s cool.

Anyway: I love the clarification on the overall direction of the company… but I’m not sure how we market it effectively2. I look around at the people in my team and its sister teams, all of us proudly holding our “Help the Hosts” cards and ready to work to continue to make Woo an amazing ecommerce platform wherever you choose to host it.

And obviously I can see the consumer value in that. It’s reassuring to know that the open source software we maintain or contribute to is the real deal and we’re not exporting a cut-down version nor are we going to try to do some kind of rug pull to coerce people into hosting with us. I think Automattic’s long track record shows that.

But how do we sell that? How do we explain that “hey, you can trust us to keep these separate goals separate within our company, so there’s never a conflict of interest and you getting the best from us is always what we want”? Personally, seeing the inside of Automattic, I’m convinced that we’re not – like so much of Big Tech – going to axe the things you depend upon3 or change the terms and conditions to the most-exploitative we can get away with4 or support your business just long enough to be able to undermine and consume it 5.

In short: I know that we’re the “good guys”. And I can see how this reorganisation reinforces that. But I can’t for the life of me see how we persuade the rest of the world of the fact6.

Any ideas?

Footnotes

1 I’ve been on Team Fire for a long while, which made my job title “Code Magician on Fire”, but now I’ll be on Team Desire which isn’t half as catchy a name but I’m sure they’ll make up for it by being the kinds of awesome human beings I’ve become accustomed to working alongside at Automattic.

2 Fortunately they pay me to code, not to do marketing.

3 Cough… Google.

4 Ahem… Facebook.

5 ${third_coughing_sound}… Amazon.

6 Seriously, it’s a good thing I’m not in marketing. I’d be so terrible at it. Also public relations. Did I ever tell you the story about the time that, as a result of a mix-up, I accidentally almost gave an interview to the Press Office at the Vatican? A story for another time, perhaps

Dan, wearing an Oxford-branded t-shirt, shrugs and looks confused in front of a screen showing Automattic's "Work With Us" page.× A laptop computer on a desk, showing a WordPress wp-admin page.×

[Bloganuary] Fun Five

This post is part of my attempt at Bloganuary 2024. Today’s prompt is:

List five things you do for fun.

This feels disappointingly like the prompt from day 2, but I’m gonna pivot it by letting my answer from three weeks ago only cover one of the five points:

  1. Code
  2. Magic
  3. Piano
  4. Play
  5. Learn

Let’s take a look at each of those, briefly.

Code

Code is poetry. Code is fun. Code is a many-splendoured thing.

This is not what real coding looks like. This is what real coding looks like.

When I’m not coding for work or coding as a volunteer, I’m often caught coding for fun. Sometimes I write WordPress-ey things. Sometimes I write other random things. I tend to open-source almost everything I write, most of it via my GitHub account.

Magic

Now I don’t work in the city centre nor have easy access to other magicians, I don’t perform as much magic as I used to. But I still try to keep my hand in and occasionally try new things; I enjoy practicing sleights when I’m doing work-related things that don’t require my hands (meetings, code reviews, waiting for the damn unit tests to run…), a tip I learned from fellow magician Andy.

My favourite go-to trick with an untampered deck of cards is my variant of the Ambitious Classic; here’s a bit from the middle of the trick from the last time I performed it in a video meeting.

You’ll usually find a few decks of cards on my desk at any given time, mostly Bikes.1

Piano

I started teaching myself piano during the Covid lockdowns as a distraction from not being able to go anywhere (apparently I’m not the only one), and as an effort to do more of what I’m bad at.2 Since then, I’ve folded about ten minutes of piano-playing3, give or take, into my routine virtually every day.

This is what piano playing looks like. But perhaps only barely.

I fully expect that I’ll never be as accomplished at it as, say, the average 8-year-old on YouTube, but that’s not what it’s about. If I take a break from programming, or meetings, or childcare, or anything, I can feel that playing music exercises a totally different part of my mind. I’d heard musicians talk about such an experience before, but I’d assumed that it was hyperbole… but from my perspective, they’re right: practicing an instrument genuinely does feel like using a part of your brain than you use for anything else, which I love!

Play

I wrote a whole other Bloganuary post on the ways in which I integrate “play” into my life, so I’ll point you at that rather than rehash anything.

A lot of my RPG-gaming takes place online, via virtual tabletops, and is perhaps the most obvious “playtime” play activities I routinely engage in.

At the weekend I dusted off Vox Populi, my favourite mod for Civilization V, my favourite4 entry in the Civilization series, which in turn is one of my favourite video game series5. I don’t get as much time for videogaming as I might like, but that’s probably for the best because a couple of hours disappeared on Sunday evening before I even blinked! It’s addictive stuff.

Learn

As I mentioned back on day 3 of bloganuary, I’m a lifelong learner. But even when I’m not learning in an academic setting, I’m doubtless learning something. I tend to alternate between fiction and non-fiction books on my bedside table. I often get lost on deep-dives through the depths of the Web after a Wikipedia article makes me ask “wait, really?” And just sometimes, I set out to learn some kind of new skill.

It’s not always wacky and off-the-wall things like basic blacksmithing that I learn. Sometimes it’s normal, practical activities like baking bread or… umm… Argentine tango?

In short: with such a variety of fun things lined-up, I rarely get the opportunity to be bored6!

Footnotes

1 I like the feel of Bicycle cards and the way they fan. Plus: the white border – which is actually a security measure on playing cards designed to make bottom-dealing more-obvious and thus make it harder for people to cheat at e.g. poker – can actually be turned to work for the magician when doing certain sleights, including one seen in the mini-video above…

2 I’m not strictly bad at it, it’s just that I had essential no music tuition or instrument experience whatsoever – I didn’t even have a recorder at primary school! – and so I was starting at square zero.

3 Occasionally I’ll learn a bit of a piece of music, but mostly I’m trying to improve my ability to improvise because that scratches an itch in a part of my brain in a way that I find most-interesting!

4 Games in the series I’ve extensively played include: Civilization, CivNet, Civilization II (also Test of Time), Alpha Centauri (a game so good I paid for it three times, despite having previously pirated it), Civilization III, Civilization IV, Civilization V, Beyond Earth (such a disappointment compared to SMAC) and Civilization VI, plus all their expansions except for the very latest one for VI. Also spinoffs/clones FreeCiv, C-Evo, and both Call to Power games. Oh, and at least two of the board games. And that’s just the ones I’ve played enough to talk in detail about: I’m not including things like Revolution which I played an hour of and hated so much I shan’t touch it again, nor either version of Colonization which I’m treating separately…

5 Way back in 2007 I identified Civilization as the top of the top 10 videogames that stole my life, and frankly that’s still true.

6 At least, not since the kids grew out of Paw Patrol so I don’t have to sit with them and watch it any more!

CapsulePress – Gemini / Spartan / Gopher to WordPress bridge

For a while now, this site has been partially mirrored via the Gemini1 and Gopher protocols.2 Earlier this year I presented hacky versions of the tools I’d used to acieve this (and made people feel nostalgic).

Now I’ve added support for Spartan3 too and, seeing as the implementations shared functionality, I’ve combined all three – Gemini, Spartan, and Gopher – into a single package: CapsulePress.

Diagram illustrating the behaviour of CapsulePress: a WordPress installation provides content, and CapsulePress makes that content available via gemini://, spartan://, and gopher:// URLs.

CapsulePress is a Gemini/Spartan/Gopher to WordPress bridge. It lets you use WordPress as a CMS for any or all of those three non-Web protocols in addition to the Web.

For example, that means that this post is available on all of:

Composite screenshot showing this blog post in, from top-left to bottom-right: (1) Firefox, via HTTPS, (2) Lagrange, via Gemini, (3) Lagrange, via Spartan, and (4) Lynx, via Gopher.

It’s also possible to write posts that selectively appear via different media: if I want to put something exclusively on my gemlog, I can, by assigning metadata that tells WordPress to suppress a post but still expose it to CapsulePress. Neat!

90s-style web banners in the style of Netscape ads, saying "Gemini now!", "Spartan now!", and "Gopher now!". Beneath then a wider banner ad promotes CapsulePress v0.1.
Using Gemini and friends in the 2020s make me feel like the dream of the Internet of the nineties and early-naughties is still alive. But with fewer banner ads.

I’ve open-sourced the whole thing under a super-permissive license, so if you want your own WordPress blog to “feed” your Gemlog… now you can. With a few caveats:

  • It’s hard to use. While not as hacky as the disparate piles of code it replaced, it’s still not the cleanest. To modify it you’ll need a basic comprehension of all three protocols, plus Ruby, SQL, and sysadmin skills.
  • It’s super opinionated. It’s very much geared towards my use case. It’s improved by the use of templates. but it’s still probably only suitable for this site for the time being, until you make changes.
  • It’s very-much unfinished. I’ve got a growing to-do list, which should be a good clue that it’s Not Finished. Maybe it never will but. But there’ll be changes yet to come.

Whether or not your WordPress blog makes the jump to Geminispace4, I hope you’ll came take a look at mine at one of the URLs linked above, and then continue to explore.

If you’re nostalgic for the interpersonal Internet – or just the idea of it, if you’re too young to remember it… you’ll find it there. (That Internet never actually went away, but it’s harder to find on today’s big Web than it is on lighter protocols.)

Footnotes

1 Also available via Gemini.

2 Also via Finger (but that’s another story).

3 Also available via Spartan.

4 Need a browser? I suggest Lagrange.

90s-style web banners in the style of Netscape ads, saying "Gemini now!", "Spartan now!", and "Gopher now!". Beneath then a wider banner ad promotes CapsulePress v0.1.× Diagram illustrating the behaviour of CapsulePress: a WordPress installation provides content, and CapsulePress makes that content available via gemini://, spartan://, and gopher:// URLs.× Composite screenshot showing this blog post in, from top-left to bottom-right: (1) Firefox, via HTTPS, (2) Lagrange, via Gemini, (3) Lagrange, via Spartan, and (4) Lynx, via Gopher.×

Better WordPress RSS Feeds

I’ve made a handful of tweaks to my RSS feed which I feel improves upon WordPress’s default implementation, at least in my use-case.1 In case any of these improvements help you, too, here’s a list of them:

Post Kinds in Titles

Since 2020, I’ve decorated post titles by prefixing them with the “kind” of post they are (courtesy of the Post Kinds plugin). I’ve already written about how I do it, if you’re interested.

Screenshot showing a Weekly Digest email from DanQ.me, with two Notes and a Repost clearly-identified.
Identifying post kinds is particularly useful for people who subscribe by email (the emails are generated off the RSS feed either daily or weekly: subscriber’s choice), who might want to see articles and videos but not care about for example checkins and reposts.

RSS Only posts

A minority of my posts are – initially, at least – publicised only via my RSS feed (and places that are directly fed by it, like email subscribers). I use a tag to identify posts to be hidden in this way. I’ve written about my implementation before, but I’ve since made a couple of additional improvements:

  1. Suppressing the tag from tag clouds, to make it harder to accidentally discover these posts by tag-surfing,
  2. Tweaking the title of such posts when they appear in feeds (using the same technique as above), so that readers know when they’re seeing “exclusive” content, and
  3. Setting a X-Robots-Tag: noindex, nofollow HTTP header when viewing such tag or a post, to discourage search engines (code for this not shown below because it’s so very specific to my theme that it’s probably no use to anybody else!).
// 1. Suppress the "rss club" tag from tag clouds/the full tag list
function rss_club_suppress_tags_from_display( string $tag_list, string $before, string $sep, string $after, int $post_id ): string {
  foreach(['rss-club'] as $tag_to_suppress){
    $regex = sprintf( '/<li>[^<]*?<a [^>]*?href="[^"]*?\/%s\/"[^>]*?>.*?<\/a>[^<]*?<\/li>/', $tag_to_suppress );
    $tag_list = preg_replace( $regex, '', $tag_list );
  }
  return $tag_list;
}
add_filter( 'the_tags', 'rss_club_suppress_tags_from_display', 10, 5 );

// 2. In feeds, tweak title if it's an RSS exclusive
function rss_club_add_rss_only_to_rss_post_title( $title ){
  $post_tag_slugs = array_map(function($tag){ return $tag->slug; }, wp_get_post_tags( get_the_ID() ));
  if ( ! in_array( 'rss-club', $post_tag_slugs ) ) return $title; // if we don't have an rss-club tag, drop out here
  return trim( "{$title} [RSS Exclusive!]" );
  return $title;
}
add_filter( 'the_title_rss', 'rss_club_add_rss_only_to_rss_post_title', 6 );

Adding a stylesheet

Adding a stylesheet to your feeds can make them much friendlier to beginner users (which helps drive adoption) without making them much less-convenient for people who know how to use feeds already. Darek Kay and Terence Eden both wrote great articles about this just earlier this year, but I think my implementation goes a step further.

Screenshot of DanQ.me's RSS feed as viewed in Firefox, showing a "Q" logo and three recent posts.
I started with Matt Webb‘s pretty-feed-v3.xsl by Matt Webb (as popularised by AboutFeeds.com) and built from there.

In addition to adding some “Q” branding, I made tweaks to make it work seamlessly with both my RSS and Atom feeds by using two <xsl:for-each> blocks and exploiting the fact that the two standards don’t overlap in their root namespaces. Here’s my full XSLT; you need to override your feed template as Terence describes to use it, but mine can be applied to both RSS and Atom.2

I’ve still got more I’d like to do with this, for example to take advantage of the thumbnail images I attach to posts. On which note…

Thumbnail images

When I first started offering email subscription options I used Mailchimp’s RSS-to-email service, which was… okay, but not great, and I didn’t like the privacy implications that came along with it. Mailchimp support adding thumbnails to your email template from your feed, but WordPress themes don’t by-default provide the appropriate metadata to allow them to do that. So I installed Jordy Meow‘s RSS Featured Image plugin which did it for me.

<item>
        <title>[Checkin] Geohashing expedition 2023-07-27 51 -1</title>
        <link>https://danq.me/2023/07/27/geohashing-expedition-2023-07-27-51-1/</link>

        ...

        <media:content url="/_q23u/2023/07/20230727_141710-1024x576.jpg" medium="image" />
        <media:description>Dan, wearing a grey Three Rings hoodie, carrying French Bulldog Demmy, standing on a path with trees in the background.</media:description>
</item>
Media attachments for RSS feeds are perhaps most-popular for podcasts, but they’re also great for post thumbnail images.

During my little redesign earlier this year I decided to go two steps further: (1) ditching the plugin and implementing the functionality directly into my theme (it’s really not very much code!), and (2) adding not only a <media:content medium="image" url="..." /> element but also a <media:description> providing the default alt-text for that image. I don’t know if any feed readers (correctly) handle this accessibility-improving feature, but my stylesheet above will, some day!

Here’s how that’s done:

function rss_insert_namespace_for_featured_image() {
  echo "xmlns:media=\"http://search.yahoo.com/mrss/\"\n";
}

function rss_insert_featured_image( $comments ) {
  global $post;
  $image_id = get_post_thumbnail_id( $post->ID );
  if( ! $image_id ) return;
  $image = get_the_post_thumbnail_url( $post->ID, 'large' );
  $image_url = esc_url( $image );
  $image_alt = esc_html( get_post_meta( $image_id, '_wp_attachment_image_alt', true ) );
  $image_title = esc_html( get_the_title( $image_id ) );
  $image_description = empty( $image_alt ) ? $image_title : $image_alt;
  if ( !empty( $image ) ) {
    echo <<<EOF
      <media:content url="{$image_url}" medium="image" />
      <media:description>{$image_description}</media:description>
    EOF;
  }
}

add_action( 'rss2_ns', 'rss_insert_namespace_for_featured_image' );
add_action( 'rss2_item', 'rss_insert_featured_image' );

So there we have it: a little digital gardening, and four improvements to WordPress’s default feeds.

RSS may not be as hip as it once was, but little improvements can help new users find their way into this (enlightened?) way to consume the Web.

If you’re using RSS to follow my blog, great! If it’s not for you, perhaps pick your favourite alternative way to get updates, from options including email, Telegram, the Fediverse (e.g. Mastodon), and more…

Update 4 September 2023: More-recently, I’ve improved WordPress RSS feeds by preventing them from automatically converting emoji into images.

Footnotes

1 The changes apply to the Atom feed too, for anybody of such an inclination. Just assume that if I say RSS I’m including Atom, okay?

2 The experience of writing this transformation/stylesheet also gave me yet another opportunity to remember how much I hate working with XSLTs. This time around, in addition to the normal namespace issues and headscratching syntax, I had to deal with the fact that I initially tried to use a feature from XSLT version 2.0 (a 22-year-old version) only to discover that all major web browsers still only support version 1.0 (specified last millenium)!

Screenshot showing a Weekly Digest email from DanQ.me, with two Notes and a Repost clearly-identified.× Screenshot of DanQ.me's RSS feed as viewed in Firefox, showing a "Q" logo and three recent posts.×

WCEU23 – Contributor Day

Among the many perks of working for a company with a history so tightly-intertwined with that of the open-source WordPress project is that license to attend WordCamps – the biggest WordPress conferences – is basically a given.

Dan, wearing an Automattic "Let's make the Web a better place" t-shirt, stands in front of a banner welcoming attendees to WordCamp Europe Athens 2023.
So yeah, right now I’m in Athens for WordCamp Europe 2023.

It’s frankly a wonder that this is, somehow, my first WordCamp. As well as using it1 and developing atop it2, of course, I’ve been contributing to WordPress since 2004 (albeit only in a tiny way, and not at all for most of the last decade!).

A table placeholder labelled "WP-CLI". It and s handful of Coke cans and disposable coffee cups are picked-out in colour on an otherwise monochrome and blurred picture.
If you already know what WP-CLI is… let’s be friends.

Today is Contributor Day, a pre-conference day in which folks new and old get together in person to hack on WordPress and WordPress-adjacent projects. So I met up with Cem, my Level 4 Dragonslayer friend, and we took an ultra-brief induction into WP-CLI3 before diving in to try to help write some code.

Dan takes a selfie from a round table covered in laptops, with people hacking at them.
Contributor Days are about many things, but perhaps their biggest value comes from lowering the barrier to becoming a new contributor to an open-source project by sitting you right next to somebody who already knows it well.

So today, as well as meeting some awesome folks, I got to write an overly-verbose justification for a bug report being invalid and implement my first PR for WP-CLI: a bugfix for a strange quirk in output formatting.

Screenshot showing a user running `wp plugin update --all --no-color` but the output putting the word "Success" in green.
The bug I fixed is slightly hard to describe (and even harder to explain why it matters), but here’s a summary: when you run a WP-CLI command that first displays a table and then the result, the result is likely to always appear in colour even if you specify --no-color.

I hope to be able to continue contributing to WP-CLI. I learned a lot about it today, and while I don’t use it as much as I used to in my multisite-management days, I still really respect its power as a tool.

MacBook showing an Automattic "Work For Us" web page, alongside a bottle of Corona Extra. A rooftop terrace garden and swimming pool can be seen in the background.
Did I mention lately how awesome my employers are? I promise my blog’s not always gonna be me shilling for them… but today it is.

Footnotes

1 Even with the monumental stack of custom code woven into DanQ.me, a keen eye will probably spot that it’s WordPress-powered.

2 Perhaps my proudest “built on WordPress” moment was my original implementation of OpenID for WordPress, back in 2005, which is completely obsolete now. But I’ve done plenty of other things, both useful (like the multisite installation used by the University of Oxford) and pointless (like making WordPress a CMS for Gemini, Gopher, and Finger) too over the last 20 years.

3 WP-CLI is… it’s like Drush but for WordPress, if that makes sense to you? If not: it’s a multifaceted command-line tool for installing, configuring, maintaining, and managing WordPress installations, and I’ve been in love with it for years.

Dan, wearing an Automattic "Let's make the Web a better place" t-shirt, stands in front of a banner welcoming attendees to WordCamp Europe Athens 2023.× A table placeholder labelled "WP-CLI". It and s handful of Coke cans and disposable coffee cups are picked-out in colour on an otherwise monochrome and blurred picture.× Dan takes a selfie from a round table covered in laptops, with people hacking at them.× Screenshot showing a user running `wp plugin update --all --no-color` but the output putting the word "Success" in green.× MacBook showing an Automattic "Work For Us" web page, alongside a bottle of Corona Extra. A rooftop terrace garden and swimming pool can be seen in the background.×

Email newsletters via RSS

I love feeds!

Maybe you’ve heard already, but I love RSS.

I love it so much that I retrofit sites without feeds into it for the convenience of my favourite reader FreshRSS: working around (for example) the lack of feeds in The Far Side (twice), in friends’ blogs, and in my URL shortener. Whether tracking my progress binging webcomic history, subscribing to YouTube channels, or filtering-out sports news, feeds are the centre of my digital life.

Illustration showing a web application with an RSS feed; the RSS feed is sending data to my RSS reader (represented by FreshRSS's icon).

 

There’s been a bit of a resurgence lately of sites whose only subscription option is email, or – worse yet – who provide certain “exclusive” content only to email subscribers.

I don’t want to go giving an actual email address to every damn service, because:

  • It’s not great for privacy, even when (as usual) I use a unique alias for each sender.
  • It’s usually harder to unsubscribe than I’d like, and rarely consistent: you need to find a recent message, click a link, sometimes that’s enough or sometimes you need to uncheck a box or click a button, or sometimes you’ll get another email with something to click in it…
  • I rarely want to be notified the very second a new issue is published; email is necessarily more “pushy” than I like a subscription to be.
  • I don’t want to use my email Inbox to keep track of which articles I’ve read/am still going to read: that’s what a feed reader is for! (It also provides tagging, bookmarking, filtering, standardised and bulk unsubscribing tools, etc.)

So what do I do? Well…

Illustration showing a web application using MailChimp to send an email newsletter to OpenTrashMail, to which FreshRSS is subscribed.

I already operate an OpenTrashMail instance for one-shot throwaway email addresses (which I highly recommend). And OpenTrashMail provides a rich RSS feed. Sooo…

How I subscribe to newsletters (in my feed reader)

If I want to subscribe to your newsletter, here’s what I do:

  1. Put an email address (I usually just bash the keyboard to make a random one, then put @-a-domain-I-control on the end, where that domain is handled by OpenTrashMail) in to subscribe.
  2. Put https://my-opentrashmail-server/rss/the-email-address-I-gave-you/rss.xml into my feed reader.
  3. That’s all. There is no step 3.

Now I get your newsletter alongside all my other subscriptions. If I want to unsubscribe I just tell my feed reader to stop polling the RSS feed (You don’t even get to find out that I’ve unsubscribed; you’re now just dropping emails into an unmonitored box, but of course I can resubscribe and pick up from where I left off if I ever want to).

Obviously this approach isn’t suitable for personalised content or sites for which your email address is used for authentication, because anybody who can guess the random email address can get the feed! But it’s ideal for those companies who’ll ocassionally provide vouchers in exchange for being able to send you other stuff to your Inbox, because you can simply pipe their content to your feed reader, then add a filter to drop anything that doesn’t contain the magic keyword: regular vouchers, none of the spam. Or for blogs that provide bonus content to email subscribers, you can get the bonus content in the same way as the regular content, right there in a folder of your reader. It’s pretty awesome.

If you don’t already have and wouldn’t benefit from running OpenTrashMail (or another trashmail system with feed support) it’s probably not worth setting one up just for this purpose. But otherwise, I can certainly recommend it.

Sisyphus: The Board Game (Digital Edition)

I’m off work sick today: it’s just a cold, but it’s had a damn good go at wrecking my lungs and I feel pretty lousy. You know how when you’ve got too much of a brain-fog to trust yourself with production systems but you still want to write code (or is that just me?), so this morning I threw together a really, really stupid project which you can play online here.

Screenshot showing Sisyphus carrying a rock up a long numbered gameboard; he's on square 993 out of 1000, but (according to the rules printed below the board) he needs to land on 1000 exactly and never roll a double-1 or else he returns to the start.
It’s a board game. Well, the digital edition of one. Also, it’s not very good.

It’s inspired by a toot by Mason”Tailsteak” Williams (whom I’ve mentioned before once or twice). At first I thought I’d try to calculate the odds of winning at his proposed game, or how many times one might expect to play before winning, but I haven’t the brainpower for that in my snot-addled brain. So instead I threw together a terrible, terrible digital implementation.

Go play it if, like me, you’ve got nothing smarter that your brain can be doing today.

Note #20798

Finally got around to implementing a super-lightweight (~20 lines of code, 1 dependency) #spring83 key generator. There are plenty of others; nobody needs this one, but it’s free if you want it:

https://github.com/Dan-Q/spring83-keygen

.well-known/links in WordPress

Via Jeremy Keith I today discovered Jim Nielsen‘s suggestion for a website’s /.well-known/links to be a place where it can host a JSON-formatted list of all of its outgoing links.

That’s a really useful thing to have in this new age of the web, where Refererer: headers are no-longer commonly passed cross-domain and Google Search no longer provides the link: operator. If you want to know if I’ve ever linked to your site, it’s a bit of a drag to find out.

JSON output from DanQ.me's .well-known/links, showing 1,150 outbound links to en.wikipedia.org domains, for topics like "Bulls and Cows", "Shebang (Unix)", "Imposter syndrome", "Interrobang", and "Blakedown".
To nobody’s surprise whatsoever, I’ve made a so many links to Wikipedia that I might be single-handedly responsible for their PageRank.

So, obviously, I’ve written an implementation for WordPress. It’s really basic right now, but the source code can be found here if you want it. Install it as a plugin and run wp outbound-links to kick it off. It’s fast: it takes 3-5 seconds to parse the entirety of danq.me, and I’ve got somewhere in the region of 5,000 posts to parse.

You can see the results at https://danq.me/.well-known/links – if you’ve ever wondered “has Dan ever linked to my site?”, now you can find the answer.

If this could be useful to you, let’s collaborate on making this into an actually-useful plugin! Otherwise it’ll just languish “as-is”, which is good enough for my purposes.

Beating Children at Mastermind

This blog post is also available as a video. Would you prefer to watch/listen to me tell you about how I’ve implemented a tool to help me beat the kids when we play Mastermind?

I swear that I used to be good at Mastermind when I was a kid. But now, when it’s my turn to break the code that one of our kids has chosen, I fail more often than I succeed. That’s no good!

Black, white, brown, blue, green, orange and yellow Mastermind pegs in a disordered heap.
If you didn’t have me pegged as a board gamer… where the hell have you been?

Mastermind and me

Maybe it’s because I’m distracted; multitasking doesn’t help problem-solving. Or it’s because we’re “Super” Mastermind, which differs from the one I had as a child in that eight (not six) peg colours are available and secret codes are permitted to have duplicate peg colours. These changes increase the possible permutations from 360 to 4,096, but the number of guesses allowed only goes up from 8 to 10. That’s hard.

A plastic Mastermind board in brown and green; it has twelve spots for guessing and shows six coloured pegs. The game has been won on the sixth guess.
The set I had as a kid was like this, I think. Photo courtesy ZeroOne; CC-BY-SA license.

Or maybe it’s just that I’ve gotten lazy and I’m now more-likely to try to “solve” a puzzle using a computer to try to crack a code using my brain alone. See for example my efforts to determine the hardest hangman words and make an adverserial hangman game, to generate solvable puzzles for my lock puzzle game, to cheat at online jigsaws, or to balance my D&D-themed Wordle clone.

Hey, that’s an idea. Let’s crack the code… by writing some code!

Screenshot showing Mastermind game from WebGamesOnline.com. Seven guesses have been made, each using only one colour for each of the four pegs, and no guesses are corect; only red pegs have never been guessed.
This online edition plays a lot like the version our kids play, although the peg colours are different. Next guess should be an easy solve!

Representing a search space

The search space for Super Mastermind isn’t enormous, and it lends itself to some highly-efficient computerised storage.

There are 8 different colours of peg. We can express these colours as a number between 0 and 7, in three bits of binary, like this:

Decimal Binary Colour
0 000 Red
1 001 Orange
2 010 Yellow
3 011 Green
4 100 Blue
5 101 Pink
6 110 Purple
7 111 White

There are four pegs in a row, so we can express any given combination of coloured pegs as a 12-bit binary number. E.g. 100 110 111 010 would represent the permutation blue (100), purple (110), white (111), yellow (010). The total search space, therefore, is the range of numbers from 000000000000 through 111111111111… that is: decimal 0 through 4,095:

Decimal Binary Colours
0 000000000000 Red, red, red, red
1 000000000001 Red, red, red, orange
2 000000000010 Red, red, red, yellow
…………
4092 111111111100 White, white, white, blue
4093 111111111101 White, white, white, pink
4094 111111111110 White, white, white, purple
4095 111111111111 White, white, white, white

Whenever we make a guess, we get feedback in the form of two variables: each peg that is in the right place is a bull; each that represents a peg in the secret code but isn’t in the right place is a cow (the names come from Mastermind’s precursor, Bulls & Cows). Four bulls would be an immediate win (lucky!), any other combination of bulls and cows is still valuable information. Even a zero-score guess is valuable- potentially very valuable! – because it tells the player that none of the pegs they’ve guessed appear in the secret code.

A plastic Mastermind board in blue and yellow with ten guess spaces and eight pegs. The sixth guess is unscored but looks likely to be the valid solution.
If one of Wordle‘s parents was Scrabble, then this was the other. Just ask its Auntie Twitter.

Solving with Javascript

The latest versions of Javascript support binary literals and bitwise operations, so we can encode and decode between arrays of four coloured pegs (numbers 0-7) and the number 0-4,095 representing the guess as shown below. Decoding uses an AND bitmask to filter to the requisite digits then divides by the order of magnitude. Encoding is just a reduce function that bitshift-concatenates the numbers together.

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/**
 * Decode a candidate into four peg values by using binary bitwise operations.
 */
function decodeCandidate(candidate){
  return [
    (candidate & 0b111000000000) / 0b001000000000,
    (candidate & 0b000111000000) / 0b000001000000,
    (candidate & 0b000000111000) / 0b000000001000,
    (candidate & 0b000000000111) / 0b000000000001
  ];
}

/**
 * Given an array of four integers (0-7) to represent the pegs, in order, returns a single-number
 * candidate representation.
 */
function encodeCandidate(pegs) {
  return pegs.reduce((a, b)=>(a << 3) + b);
}

With this, we can simply:

  1. Produce a list of candidate solutions (an array containing numbers 0 through 4,095).
  2. Choose one candidate, use it as a guess, and ask the code-maker how it scores.
  3. Eliminate from the candidate solutions list all solutions that would not score the same number of bulls and cows for the guess that was made.
  4. Repeat from step #2 until you win.

Step 3’s the most important one there. Given a function getScore( solution, guess ) which returns an array of [ bulls, cows ] a given guess would score if faced with a specific solution, that code would look like this (I’m convined there must be a more-performant way to eliminate candidates from the list with XOR bitmasks, but I haven’t worked out what it is yet):

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/**
 * Given a guess (array of four integers from 0-7 to represent the pegs, in order) and the number
 * of bulls (number of pegs in the guess that are in the right place) and cows (number of pegs in the
 * guess that are correct but in the wrong place), eliminates from the candidates array all guesses
 * invalidated by this result. Return true if successful, false otherwise.
 */
function eliminateCandidates(guess, bulls, cows){
  const newCandidatesList = data.candidates.filter(candidate=>{
    const score = getScore(candidate, guess);
    return (score[0] == bulls) && (score[1] == cows);
  });
  if(newCandidatesList.length == 0) {
    alert('That response would reduce the candidate list to zero.');
    return false;
  }
  data.candidates = newCandidatesList;
  chooseNextGuess();
  return true;
}

I continued in this fashion to write a full solution (source code). It uses ReefJS for component rendering and state management, and you can try it for yourself right in your web browser. If you play against the online version I mentioned you’ll need to transpose the colours in your head: the physical version I play with the kids has pink and purple pegs, but the online one replaces these with brown and black.

Testing the solution

Let’s try it out against the online version:

As expected, my code works well-enough to win the game every time I’ve tried, both against computerised and in-person opponents. So – unless you’ve been actively thinking about the specifics of the algorithm I’ve employed – it might surprise you to discover that… my solution is very-much a suboptimal one!

A young boy sits cross-legged on the floor, grinning excitedly at a Mastermind board (from the code-maker's side).
My code has only failed to win a single game… and that turned out to because my opponent, playing overexcitedly, cheated in the third turn. To be fair, my code didn’t lose either, though: it identified that a mistake must have been made and we declared the round void when we identified the problem.

My solution is suboptimal

A couple of games in, the suboptimality of my solution became pretty visible. Sure, it still won every game, but it was a blunt instrument, and anybody who’s seriously thought about games like this can tell you why. You know how when you play e.g. Wordle (but not in “hard mode”) you sometimes want to type in a word that can’t possibly be the solution because it’s the best way to rule in (or out) certain key letters? This kind of strategic search space bisection reduces the mean number of guesses you need to solve the puzzle, and the same’s true in Mastermind. But because my solver will only propose guesses from the list of candidate solutions, it can’t make this kind of improvement.

Animation showing how three clues alone are sufficient to derive a unique answer from the search space of the original "break into us" lock puzzle.
My blog post about Break Into Us used a series of visual metaphors to show search space dissection, including this one. If you missed it, it might be worth reading.

Search space bisection is also used in my adverserial hangman game, but in this case the aim is to split the search space in such a way that no matter what guess a player makes, they always find themselves in the larger remaining portion of the search space, to maximise the number of guesses they have to make. Y’know, because it’s evil.

Screenshot showing a single guess row from Online Mastermind, with the guess Red, Red, Green, Green.
A great first guess, assuming you’re playing against a random code and your rules permit the code to have repeated colours, is a “1122” pattern.

There are mathematically-derived heuristics to optimise Mastermind strategy. The first of these came from none other than Donald Knuth (legend of computer science, mathematics, and pipe organs) back in 1977. His solution, published at probably the height of the game’s popularity in the amazingly-named Journal of Recreational Mathematics, guarantees a solution to the six-colour version of the game within five guesses. Ville [2013] solved an optimal solution for a seven-colour variant, but demonstrated how rapidly the tree of possible moves grows and the need for early pruning – even with powerful modern computers – to conserve memory. It’s a very enjoyable and readable paper.

But for my purposes, it’s unnecessary. My solver routinely wins within six, maybe seven guesses, and by nonchalantly glancing at my phone in-between my guesses I can now reliably guess our children’s codes quickly and easily. In the end, that’s what this was all about.

Black, white, brown, blue, green, orange and yellow Mastermind pegs in a disordered heap.× A plastic Mastermind board in brown and green; it has twelve spots for guessing and shows six coloured pegs. The game has been won on the sixth guess.× Screenshot showing Mastermind game from WebGamesOnline.com. Seven guesses have been made, each using only one colour for each of the four pegs, and no guesses are corect; only red pegs have never been guessed.× A plastic Mastermind board in blue and yellow with ten guess spaces and eight pegs. The sixth guess is unscored but looks likely to be the valid solution.× A young boy sits cross-legged on the floor, grinning excitedly at a Mastermind board (from the code-maker's side).× Screenshot showing a single guess row from Online Mastermind, with the guess Red, Red, Green, Green.×

DNDle (Wordle, but with D&D monster stats)

Don’t have time to read? Just start playing:

Play DNDle

There’s a Wordle clone for everybody

Am I too late to get onto the “making Wordle clones” bandwagon? Probably; there are quite a few now, including:

Screenshot showing a WhatsApp conversation. Somebody shares a Wordle-like "solution" board but it's got six columns, not five. A second person comments "Hang on a minute... that's not Wordle!"
I’m sure that by now all your social feeds are full of people playing Wordle. But the cool nerds are playing something new…

Now, a Wordle clone for D&D players!

But you know what hasn’t been seen before today? A Wordle clone where you have to guess a creature from the Dungeons & Dragons (5e) Monster Manual by putting numeric values into a character sheet (STR, DEX, CON, INT, WIS, CHA):

Screenshot of DNDle, showing two guesses made already.
Just because nobody’s asking for a game doesn’t mean you shouldn’t make it anyway.

What are you waiting for: go give DNDle a try (I pronounce it “dindle”, but you can pronounce it however you like). A new monster appears at 10:00 UTC each day.

And because it’s me, of course it’s open source and works offline.

The boring techy bit

  • Like Wordle, everything happens in your browser: this is a “backendless” web application.
  • I’ve used ReefJS for state management, because I wanted something I could throw together quickly but I didn’t want to drown myself (or my players) in a heavyweight monster library. If you’ve not used Reef before, you should give it a go: it’s basically like React but a tenth of the footprint.
  • A cache-first/background-updating service worker means that it can run completely offline: you can install it to your homescreen in the same way as Wordle, but once you’ve visited it once it can work indefinitely even if you never go online again.
  • I don’t like to use a buildchain that’s any more-complicated than is absolutely necessary, so the only development dependency is rollup. It resolves my import statements and bundles a single JS file for the browser.
Screenshot showing a WhatsApp conversation. Somebody shares a Wordle-like "solution" board but it's got six columns, not five. A second person comments "Hang on a minute... that's not Wordle!"×

Minification vs the GPL

A not-entirely-theoretical question about open source software licensing came up at work the other day. I thought it was interesting enough to warrant a quick dive into the philosophy of minification, and how it relates to copyleft open source licenses. Specifically: does distributing (only) minified source code violate the GPL?

If you’ve come here looking for a legally-justifiable answer to that question, you’re out of luck. But what I can give you is a (fictional) story:

TheseusJS is slow

TheseusJS is a (fictional) Javascript library designed to be run in a browser. It’s released under the GPLv3 license. This license allows you to download and use TheseusJS for any purpose you like, including making money off it, modifying it, or redistributing it to others… but it requires that if you redistribute it you have to do so under the same license and include the source code. As such, it forces you to share with others the same freedoms you enjoy for yourself, which is highly representative of some schools of open-source thinking.

Screenshot showing TheseusJS's GitHub page. The project hasn't been updated in a year, and that was just to add a license: no code has been changed in 12 years.
It’s a cool project, but it really needs some maintenance this side of 2010.

It’s a great library and it’s used on many websites, but its performance isn’t great. It’s become infamous for the impact it has on the speed of the websites it’s used on, and it’s often the butt of jokes by developers: “Man, this website’s slow. Must be running Theseus!”

The original developer has moved onto his new project, Moralia, and seems uninterested in handling the growing number of requests for improvements. So I’ve decided to fork it and make my own version, FastTheseusJS and work on improving its speed.

FastTheseusJS is fast

I do some analysis and discover the single biggest problem with TheseusJS is that the Javascript file itself is enormous. The original developer kept all of the copious documentation in comments in the file itself, and for some reason it doesn’t even compress well. When you use TheseusJS on a website it takes a painfully long time for a browser to download it, if it’s not precached.

Screenshot showing a website for the TheseusJS API. It's pretty labyrinthine (groan).
Nobody even uses the documentation in the comments: there’s a website with a fully-documented API.

My first release of FastTheseusJS, then, removes virtually of the comments, replacing them with a single comment at the top pointing developers to a website where the API is fully documented. While I’m in there anyway, I also fix a minor bug that’s been annoying me for a while.

v1.1.0 changes

  • Forked from TheseusJS v1.0.4
  • Fixed issue #1071 (running mazeSolver() without first connecting <String> component results in endless loop)
  • Removed all comments: improves performance considerably

I discover another interesting fact: the developer of TheseusJS used a really random mixture of tabs and spaces for indentation, sometimes in the same line! It looks… okay if you set your editor up just right, but it’s pretty hideous otherwise. That whitespace is unnecessary anyway: the codebase is sprawling but it seldom goes more than two levels deep, so indentation levels don’t add much readability. For my second release of FastTheseusJS, then, I remove this extraneous whitespace, as well as removing the in-line whitespace inside parameter lists and the components of for loops. Every little helps, right?

v1.1.1 changes

  • Standardised whitespace usage
  • Removed unnecessary whitespace

Some of the simpler functions now fit onto just a single line, and it doesn’t even inconvenience me to see them this way: I know the codebase well enough by now that it’s no disadvantage for me to edit it in this condensed format.

Screenshot of a block of Javascript code intended using semicolons rather than tabs or spaces.
Personally, I’ve given up on the tabs-vs-spaces debate and now I indent my code using semicolons. (That’s clearly a joke. Don’t flame me.)

In the next version, I shorten the names of variables and functions in the code.

For some reason, the original developer used epic rambling strings for function names, like the well-known function dedicateIslandTempleToTheImageOfAGodBeforeOrAfterMakingASacrificeWithOrWithoutDancing( boolBeforeMakingASacrifice, objectImageOfGodToDedicateIslandTempleTo, stringNmeOfPersonMakingDedication, stringOrNullNameOfLocalIslanderDancedWith). That one gets called all the time internally and isn’t exposed via the external API so it might as well be shortened to d=(i,j,k,l,m)=>. Now all the internal workings of the library are each represented with just one or two letters.

v1.1.2 changes

  • Shortened/standarised non-API variable and function names – improves performance

I’ve shaved several kilobytes off the monstrous size of TheseusJS and I’m very proud. The original developer says nice things about my fork on social media, resulting in a torrent of downloads and attention. Within a certain archipelago of developers, I’m slightly famous.

But did I violate the license?

But then a developer says to me: you’re violating the license of the original project because you’re not making the source code available!

A man in a suit sits outdoors with a laptop and a cup of coffee. He is angry and frustrated, and a bubble shows that he is thinking:"why can't people respect the fucking license?!"
This happens every day. Probably not to this same guy every time though, but you never know. Original photo by Andrea Piacquadio.

They claim that my bugfix in the first version of FastTheseusJS represents a material change to the software, and that the changes I’ve made since then are obfuscation: efforts short of binary compilation that aim to reduce the accessibility of the source code. This fails to meet the GPL‘s definition of source code as “the preferred form of the work for making modifications to it”. I counter that this condensed view of the source code is my “preferred” way of working with it, and moreover that my output is not the result of some build step that makes the code harder to read, the code is just hard to read as a result of the optimisations I’ve made. In ambiguous cases, whose “preference” wins?

Did I violate the license? My gut feeling is that no, all of my changes were within the spirit and the letter of the GPL (they’re a terrible way to write code, but that’s not what’s in question here). Because I manually condensed the code, did so with the intention that this condensing was a feature, and continue to work directly with the code after condensing it because I prefer it that way… that feels like it’s “okay”.

But if I’d just run the code through a minification tool, my opinion changes. Suppose I’d run minify --output fasttheseus.js theseus.js and then deleted my copy of theseus.js. Then, making changes to fasttheseus.js and redistributing it feels like a violation to me… even if the resulting code is the same as I’d have gotten via the “manual” method!

I don’t know the answer (IANAL), but I’ll tell you this: I feel hypocritical for saying one piece of code would not violate the license but another identical piece of code would, based only on the process the developer followed to produce it. If I replace one piece of code at a time with less-readable versions the license remains intact, but if I replace them all at once it doesn’t? That doesn’t feel concrete nor satisfying.

Screenshot showing highly-minified HTML code (for this page) which is still reasonably readable.
Sure, I can write a blog post in just one line of code. It’ll just be a really, really, really long line… (Still perfectly readable, though!)

This isn’t an entirely contrived example

This example might seem highly contrived, and that’s because it is. But the grey area between the extremes is where the real questions are. If you agree that redistribution of (only) minified source code violates the GPL, you’re left asking: at what point does the change occur? Code isn’t necessarily minified or not-minified: there are many intermediate steps.

If I use a correcting linter to standardise indentation and whitespace – switching multiple spaces for the appropriate number of tabs, removing excess line breaks etc. (or do the same tasks manually) I’m sure you’d agree that’s fine. If I have it replace whole-function if-blocks with hoisted return statements, that’s probably fine too. If I replace if blocks with ternery operators or remove or shorten comments… that might be fine, but probably depends upon context. At some point though, some way along the process, minification goes “too far” and feels like it’s no longer within the limitations of the license. And I can’t tell you where that point is!

This issue’s even more-complicated with some other licenses, e.g. the AGPL, which extends the requirement to share source code to hosted applications. Suppose I implement a web application that uses an AGPL-licensed library. The person who redistributed it to me only gave me the minified version, but they gave me a web address from which to acquire the full source code, so they’re in the clear. I need to make a small patch to the library to support my service, so I edit it right into the minified version I’ve already got. A user of my hosted application asks for a copy of the source code, so I provide it, including the edited minified library… am I violating the license for not providing the full, unminified version, even though I’ve never even seen it? It seems absurd to say that I would be, but it could still be argued to be the case.

Diagram showing how permissive software licenses are generally compatible for use in LGPL or MPL licensed software, which are then compatible for use (except MPL) in GPL licensed software, which are in turn compatible for use (except GPL 2) with AGPL licensed software.
I love diagrams like this, which show license compatibility of different open source licenses. Adapted from a diagram by Carlo Daffara, in turn adapted from a diagram by David E. Wheeler, used under a CC-BY-SA license.

99% of the time, though, the answer’s clear, and the ambiguities shown above shouldn’t stop anybody from choosing to open-source their work under GPL, AGPL (or any other open source license depending on their preference and their community). Perhaps the question of whether minification violates the letter of a copyleft license is one of those Potter Stewart “I know it when I see it” things. It certainly goes against the spirit of the thing to do so deliberately or unnecessarily, though, and perhaps it’s that softer, more-altruistic goal we should be aiming for.

Screenshot showing TheseusJS's GitHub page. The project hasn't been updated in a year, and that was just to add a license: no code has been changed in 12 years.× Screenshot showing a website for the TheseusJS API. It's pretty labyrinthine (groan).× Screenshot of a block of Javascript code intended using semicolons rather than tabs or spaces.× A man in a suit sits outdoors with a laptop and a cup of coffee. He is angry and frustrated, and a bubble shows that he is thinking:"why can't people respect the fucking license?!"× Screenshot showing highly-minified HTML code (for this page) which is still reasonably readable.× Diagram showing how permissive software licenses are generally compatible for use in LGPL or MPL licensed software, which are then compatible for use (except MPL) in GPL licensed software, which are in turn compatible for use (except GPL 2) with AGPL licensed software.×

From Synergy to Barrier

I’ve been using Synergy for a long, long time. By the time I wrote about my admiration of its notification icon back in 2010 I’d already been using it for some years. But this long love affair ended this week when I made the switch to its competitor, Barrier.

Screenshot showing some pre-1.3 version of Synergy running on Windows Vista.
I’m not certain exactly when I took this screenshot (which I shared with Kit while praising Synergy), but it’s clearly a pre-1.4 version and those look distinctly like Windows Vista’s ugly rounded corners, so I’m thinking no later than 2009?

If you’ve not come across it before: Synergy was possibly the first multiplatform tool to provide seamless “edge-to-edge” sharing of a keyboard and mouse between multiple computers. Right now, for example, I’m sitting in front of Cornet, a Debian 11 desktop, Idiophone, a Macbook Pro docked to a desktop monitor, and Renegade, a Windows desktop. And I can move my mouse cursor from one, to the other, to the next, interacting with them all as if I were connected directly to it.

There have long been similar technologies. KVM switches can do this, as can some modern wireless mice (I own at least two such mice!). But none of them are as seamless as what Synergy does: moving from computer to computer as fast as you can move your mouse and sharing a clipboard between multiple devices. I also love that I can configure my set-up around how I work, e.g. when I undock my Macbook it switches from ethernet to wifi, this gets detected and it’s automatically removed from the cluster. So when I pick up my laptop, it magically stops being controlled by my Windows PC’s mouse and keyboard until I dock it again.

Illustration showing a Debian desktop called Cornet, a Mac laptop with attached monitor called Idiophone, and a Windows desktop called Renegade. All three share a single keyboard and mouse using Barrier.

Synergy’s published under a hybrid model: open-source components, with paid-for extra features. It used to provide more in the open-source offering: you could download a fully-working copy of the software and use it without limitation, losing out only on a handful of features that for many users were unnecessary. Nontheless, early on I wanted to support the development of this tool that I used so much, and so I donated money towards funding its development. In exchange, I gained access to Synergy Premium, and then when their business model changed I got grandfathered-in to a lifetime subscription to Synergy Pro.

I continued using Synergy all the while. When their problem-stricken 2.x branch went into beta, I was among the testers: despite the stability issues and limitations, I loved the fact that I could have what was functionally multiple co-equal “host” computers, and – when it worked – I liked the slick new configuration interface it sported. I’ve been following with bated breath announcements about the next generation – Synergy 3 – and I’ve registered as an alpha tester for when the time comes.

If it sounds like I’m a fanboy… that’d probably be an accurate assessment of the situation. So why, after all these years, have I jumped ship?

Email from Symless to Dan, reading: "Thank you for contacting Synergy Support. My name is Kim and I am happy to assist you. We do not have a download option for the 32 bit version of Debian 10. We currently only have the options available in the members area. Feel free to reach out if you have any further questions or concerns."
Dear Future Dan. If you ever need a practical example of where open-source thinking provides a better user experience than arbritrarily closed-source products, please see above. Yours, Past Dan.

I’ve been aware of Barrier since the project started, as a fork of the last open-source version of the core Synergy program. Initially, I didn’t consider Barrier to be a suitable alternative for me, because it lacked features I cared about that were only available in the premium version of Synergy. As time went on and these features were implemented, I continued to stick with Synergy and didn’t bother to try out Barrier… mostly out of inertia: Synergy worked fine, and the only thing Barrier seemed to offer would be a simpler set-up (because I wouldn’t need to insert my registration details!).

This week, though, as part of a side project, I needed to add an extra computer to my cluster. For reasons that are boring and irrelevant and so I’ll spare you the details, the new computer’s running the 32-bit version of Debian 11.

I went to the Symless download pages and discovered… there isn’t a Debian 11 package. Ah well, I think: the Debian 10 one can probably be made to work. But then I discover… there’s only a 64-bit version of the Debian 10 binary. I’ll note that this isn’t a fundamental limitation – there are 32-bit versions of Synergy available for Windows and for ARMhf Raspberry Pi devices – but a decision by the developers not to support that platform. In order to protect their business model, Synergy is only available as closed-source binaries, and that means that it’s only available for the platforms for which the developers choose to make it available.

So I thought: well, I’ll try Barrier then. Now’s as good a time as any.

Screenshot showing Mac computer "Idiophone" being configured in Barrier to connect to server "Renegade".
Setting up Barrier in place of Synergy was pretty familiar and painless.

Barrier and Synergy aren’t cross-compatible, so first I had to disable Synergy on each machine in my cluster. Then I installed Barrier. Like most popular open-source software, this was trivially easy compared to Synergy: I just used an appropriate package manager by running choco install barrier, brew install barrier, and apt install barrier to install on each of the Windows, Mac, and Debian computers, respectively.

Configuring Barrier was basically identical to configuring Synergy: set up the machine names, nominate one the server, and tell the server what the relative positions are of each of the others’ screens. I usually bind the “scroll lock” key to the “lock my cursor to the current screen” function but I wasn’t permitted to do this in Barrier for some reason, so I remapped my scroll lock key to some random high unicode character and bound that instead.

Getting Barrier to auto-run on MacOS was a little bit of a drag – in the end I had to use Automator to set up a shortcut that ran it and loaded the configuration, and set that to run on login. These little touches are mostly solved in Synergy, but given its technical audience I don’t imagine that anybody is hugely inconvenienced by them. Nonetheless, Synergy clearly retains a slightly more-polished experience.

Altogether, switching from Synergy to Barrier took me under 15 minutes and has so far offered me a functionally-identical experience, except that it works on more devices, can be installed via my favourite package managers, and doesn’t ask me for registration details before it functions. Synergy 3’s going to have to be a big leap forward to beat that!

Screenshot showing some pre-1.3 version of Synergy running on Windows Vista.× Email from Symless to Dan, reading: "Thank you for contacting Synergy Support. My name is Kim and I am happy to assist you. We do not have a download option for the 32 bit version of Debian 10. We currently only have the options available in the members area. Feel free to reach out if you have any further questions or concerns."× Screenshot showing Mac computer "Idiophone" being configured in Barrier to connect to server "Renegade".× Illustration showing a Debian desktop called Cornet, a Mac laptop with attached monitor called Idiophone, and a Windows desktop called Renegade. All three share a single keyboard and mouse using Barrier.×