The #cssday photos have been published and they are great. Love them.

https://cssday.nl/2026/pix/photos/

But these... These made my day. These were taken during my talk and it makes all of the work I put into it worth it. ❤️

Not this fall, but the this conference needs to be included as well:

State of the Browser organised by
@webstandards will be back in 2027 on the 6th of March in the Barbican in London🇬🇧

I've already got my ticket – just £80, which is a steal.

🎟️ 2027.stateofthebrowser.com

Next: HalfStack is back! November 26th in Vienna🇦🇹

Another favourite. I am kind of part of the furniture, because this is going to be the 15th time I'm speaking at HalfStack 😅

Tickets are just €200 euro and with this code you'll get 20% off:
Niels_HSVienna26_Awesome20

🎟️ halfstackconf.com/vienna

Next: @ffconf in Brighton🇬🇧

This conference has been on my list for more than 10 years. I've heard so many great things, but somehow never managed to attend. But this year I am not only heading over to Brighton, but I'll actually be on stage.

Tickets will be on sale next week:
🎟️ 2026.ffconf.org

First up:

Fronteers Dark Mode in Dordrecht 🇳🇱 on October 2nd. With Cyd Stumpel, @heydon, @csswizardry, @tunetheweb and Anjana Vakil. And @jaffathecake as our MC.

An amazing location and tickets only cost €99, and include dinner. Don't miss this!

🎟️ fronteersconf.org

And, do want me to speak about CSS DOOM at your conference, DM me!

It's been a great year for conferences.

I've spoken at @btconf and @cssday and I've been so lucky to attend so many others, like State of the Browser, Web Day Out and Smashing Conference.

It's sharing knowledge, learning and getting inspired. But mostly the community.

I will be posting about some conference that you should visit this fall. I will be at all of them – either organising myself or speaking. If you have any more tips for some great conferences that I should visit, let me know!

Today exactly 10 years ago, I spoke at CSS Day.

Around that time I created a list of a handful of conference that I would love to speak at. And I am so lucky that was able to tick off most of them over the last 10 years. I even got to speak again at CSS Day last week.

Just one left... for now.

Dropped my stuff off at the #cssday venue. Like you do. Totally normal.

A PSA for the #cssday attendees:

It is perfectly safe to attend this year. Left my CSS Flamethrower at home. Apparently they don’t want me to burn the venue down.

But no worries. I am only bringing an oscilloscope - it been repaired since it exploded last year - and lasers. Perfectly safe.

On my way to #cssday, having a stop with some coffee and working on finishing my demos. What can go wrong. Totally prepared. Like a professional.

Anyway... the talk is done. Rehearsed a couple of times. Happy with the pace and I still have 10 - 15 minutes left for the demos that I have planned and Q&A.

Panic over.

RE: https://front-end.social/@html5test/116686493760532281

Every time I decide to write a talk I underestimate the time I need. I do have a rough idea, but there is this whole period of me just making random slides. Sometimes weeks.

Then suddenly I am happy. Build the rest of the talk in a day or two. Way too long. Cut in half. And it just fits together.

I haven't yet made plans for speaking at conferences this fall – limited time and writing another talk kind of felt too much...

Now that the CSS Day talk is ready, I really think the CSS DOOM chapter would work really well as a standalone talk.

Hit me up in my DMs – love to talk about CSS DOOM

This weekend was full-panic mode for #cssday as I had not a single slide or even an outline. And the conference is next week.

It took a couple of days, but last night I finished it and thought I could relax again.

Did a full run-through today and I’m about 15 minutes long. Back to panic mode.

RE: https://mastodon.social/@btconf/116651922667550532

It has been such an honour to be on the Beyond Tellerrand stage. I've given dozens of talks and this one felt very much like a personal journey through some projects I never meant to show on stage.

I had so much fun creating all of this and I think it shows in the video. Thank you, Marc!

I can't believe this actually works.

The game loop sends renderer commands to an orchestrator that fans out the commands to multiple local completely independent renderers.

Each renderer gets the same commands and can decide to override the camera position.

One of the things I started doing recently is to add recording and visualisations straight into my demos. Great to export and then include in a talk.

In this case I am showing 4 different renders, from my original oscilloscope version of DOOM and several intermediate steps of the CSS renderer.

I guess this is a sign that I should start with my #CSSDay presentation 😬

I just saw the full schedule for #cssday and oh my... just look at all of those names. 🤩 The best and the brightest of CSS all in one room and then there is also me. No pressure, no pressure... It's gonna be fine 😅

https://cssday.nl/schedule.html

Been using Claude Code to add network support to cssDOOM and... I have opinions:

Claude is brilliant and able to solve complex problems. But it uses band-aids and shortcuts to achieve that. It is an extremely fast lazy programmer that is able to create technical debt quicker than any human being.

Multiplayer cssDOOM on your phone? Yeah, it works. Just no good way to control it. But yeah. It can render two scenes side-by-side without any major issues. 🤯

If only you could start a network game from your phone so your friends can join you… coming soon 😱

In theory it could do four players. But two is pretty much the maximum the browser can render simultaneously.

But that is okay. Rendering one DOOM in CSS is already crazy. Rendering two at the same time is insane. Yet it works.

On a side note: my eleven year old is already beating me.

Made progress with cssDOOM last evening.

Created a special multi-player deathmatch version for CSS Day that runs in kiosk mode. It uses a video wall controller to split up the screen into sections. On the computer it is just one full screen window, but it drives two separate screens.

RE: https://podcasts.social/@workingdraft/116560103634569468

It is always fun to talk about my weird little projects, but this turned in to such a lovely chat. Want to know a bit more background about cssDOOM, my bad clock project and CSS on oscilloscopes? Check it out!

Sometimes your rabbit hole has another rabbit hole which has another rabbit hole. Not even sure how many levels deep I am in this right now.

Yes - network cssDOOM is coming – want to do it right – but last night I spend 4 hours working on recreating the DOOM letters as COLR/CPAL web font.

I know this is getting ridiculous, should I also add network play for cssDOOM?

The whole infrastructure had separated rendering and game loop from the start. Extended this to support rendering using a message channel. Using BroadcastChannel right now, but no reason why it could not be WebRTC.

Maybe have a Hammerspoon script running in the background that monitors if the browser is still active, and if it isn't it will automatically start it. Might be helpful in both scenarios.

The whole goal is to have something playable at CSS Day with two monitors.

Two possible solutions: use split screen and a video wall controller to direct each side to a different monitor. Should work very well. Very solid. Just one browser, one window.

The other solution is to connect each screen and simply use two windows and full screen each. Maybe a bit more fragile. The communication between the two windows is pretty solid, but what if it crashes... who is going to start it up again?

Deathmatch cssDOOM is coming soon! Still plenty of small issues, but it works already pretty well.

Added side-by-side and also multi-window. Has one advantage, that if the other player gets annoying and tries to kill you, you can just close his window and you win.