mastodon 4.7.3CTO of Salonhub. Creator of https://html5test.com, writes at https://nielsleenheer.com, team @FronteersConf, Google Developers Expert, Invite me to speak at your event.
And this is what I've been spending my evenings on lately. A decoder for receipt printer protocols. You can take the bytes that get send to a receipt printer and inspect the commands that are inside of it. And... actually see a render of the receipt.
Only useful for a hand full of people. And me.
I've seen Heydon's talk a week or two ago at @smashingconf@mastodon.social and it was amazing. I just loved it so much.
So if you want to see it... come down to Dordrecht in The Netherlands... A handful of tickets are still available.
Two weeks from now Fronteers Dark Mode will happen in Dordrecht in The Netherlands. There are still a few tickets left. Be quick ⚠️
Join us for an afternoon and evening of great talks. With a spectacular line up: Anjana Vakil, @tunetheweb@mastodon.social, @Cyd@front-end.social, @csswizardry@webperf.social and @heydon@front-end.social.
And let's not forget our amazing MC:
@jaffathecake@mastodon.social.
Tickets are just €99 ⭐️ and a two-course dinner is included as well 🍽️ @fronteers@front-end.social members will get a 50 euro discount.
🎟️ www.fronteersconf.org
Fronteers Dark Mode conference is next week! Monday I'll send badges to the printer... which means if you want a proper badge... sign up now!
We've got a handful of tickets left and they are only €100 for an evening of front-end talks by some amazing speakers.
Over the years I have brought some really weird things through airport security. I’ve set off the alarms once - they closed down the lane and started shouting in panic because it looked really serious on the scanners.
But never a vintage oscilloscope. Until today. Freiburg, here we come!
"Oscilloscopes & Other Bad Ideas"
I've been so swamped in work that I completely forgot that I am going to give a talk at the @smashingconf@mastodon.social Jam Session next Monday. But with a title like that I already know it's going to be good.
https://smashingconf.com/freiburg-2026/jam-session
Now... is there any way I can bring an actual vintage oscilloscope with me on the plane to Freiburg? 🤔
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@mastodon.world 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
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.
Take a Joy-Con and connect it with WebHID, draw a picture in the air and capture it with the sensors. Create an SVG path and insert in the DOM. Apply CSS styling. Sample the DOM and use WebUSB to convert to ILDA and send it to a laser projector.
I created the worlds most complicated laserpointer…
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.
Am I really doing this? Maybe... Not even sure if I can pull this off in about a month or so before CSS Day.
Wouldn't it be cool if you could play cssDOOM during the breaks and try to beat other attendees in a two-player Death Match game.
And I still have to write my talk too...
This is happening! Multi-player cssDOOM death match. Rendering was already pretty much decoupled from gameplay, so the two side-by-side viewports were *almost* free. Still so much work to do, but made significant progress.
In other news, I did not get much sleep last night.
Smoke machine powered by CSS!
Fully based on web platform tech, such as WebUSB for the DMX connection and CSS for controlling everything.
My projects can sometimes get a little bit out of hand. Want to know more? Come see my talk at @btconf@mastodon.social
First up:
Fronteers Dark Mode in Dordrecht 🇳🇱 on October 2nd. With Cyd Stumpel, @heydon@front-end.social, @csswizardry@webperf.social, @tunetheweb@mastodon.social and Anjana Vakil. And @jaffathecake@mastodon.social as our MC.
An amazing location and tickets only cost €99, and include dinner. Don't miss this!
🎟️ fronteersconf.org
Arrived in Amsterdam for @smashingconf@mastodon.social and booked an apartment for the coming days.
But… I did not expect to step into a Rembrandt or Vermeer painting… 🤩
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
Most of my talk preparations follow this pattern:
1. Idea
2. Worry about having enough content
3. Worry more about finishing 20 minutes early
4. Make slides
5. Practice
6. Panic, because it is 20 minute over time
7. Remove about a third of my talk
8. Panic, because I removed all the good jokes...
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.
First talk of the year is done: CSS is DOOMed, which was just a very last minute idea for the @smashingconf@mastodon.social Jam Sessions.
10 minutes. No preparations. No slides. Off the cuff. But I had lots of fun playing cssDOOM and showing how it works under the hood.
HTML DOM in Canvas? No. DOOM-ception in Canvas.
Maybe I should be working on my slides for Friday, instead I'm at @smashingconf.com creating a playable DOOM terminal in my cssDOOM project. It is a Canvas with an iframe of cssDOOM. And... it works. You can play DOOM in DOOM.
I am so honoured to be part of #btconf this year. This conference has been such a huge inspiration to me over the years. Been working on this talk for at least a year and expect chaotic energy with lots of weird and wonderful web experiments.
Sometimes I feel like I have too many projects. I move from one to the other and old projects get ignored because I am working on something new and shiny.
But that chaos also helps me be creative and challenge me to improve my skills. But today I'm feeling like a mad professor. In a good way.
Great! My clock now randomly thinks it is a VCR. And nobody knows how to set the time on a VCR so it just blinks 12:00.
Also it sometimes it forgets to reset after midnight so it goes from 23:59 to 24:00 to 25:00 and on.
And yes. I am using a round display for a square digital clock…
Next: @ffconf@social.ffconf.org 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
RE: @html5test@front-end.social
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.
Over the last week I've fixed some cssDOOM issues and improved the gameplay to better match the original game. And the best part – because it is just a website, you don't have to download any updates.
Best browser to run this is still latest Firefox, with Safari a good second.
Is it just me, or has Keynote has become terrible to use lately. Copying text blocks changes the font.... Copy source code... pasting a table?!?!
