Niels Leenheer
@html5test.com
CTO of Salonhub. Creator of http://html5test.com, writes at http://nielsleenheer.com, team @FronteersConf, Google Developers Expert, Invite me to speak at your event.
As I prepare to go back to Tromsø airport for my flight home, I still can't believe what I witnessed last night. There are a handful of nights that I will remember for the rest of my life, and this is one of them. Yesterday I felt pure joy and you could hear it across that whole small beach.
January 11, 2026 at 6:23 AM
As I prepare to go back to Tromsø airport for my flight home, I still can't believe what I witnessed last night. There are a handful of nights that I will remember for the rest of my life, and this is one of them. Yesterday I felt pure joy and you could hear it across that whole small beach.
30 minutes ago in Tromsø. The CME has arrived @vincentledvina.bsky.social
January 10, 2026 at 8:58 PM
30 minutes ago in Tromsø. The CME has arrived @vincentledvina.bsky.social
Me walking to the pickup point of the Northern Lights tour…
January 10, 2026 at 4:20 PM
Me walking to the pickup point of the Northern Lights tour…
Yesterday was another great night for the Northern Lights here in Tromsø. Very different from the night before, but just as beautiful. One more night to go 🤞🏻
January 10, 2026 at 11:00 AM
Yesterday was another great night for the Northern Lights here in Tromsø. Very different from the night before, but just as beautiful. One more night to go 🤞🏻
Took a second camera with me this trip to shoot time-lapses. Just a few quick renders, but really satisfied with the result. This is of course speed up, quite a bit. But the northern lights were really dancing yesterday. Swirling and moving right before your eyes.
January 9, 2026 at 10:20 AM
Took a second camera with me this trip to shoot time-lapses. Just a few quick renders, but really satisfied with the result. This is of course speed up, quite a bit. But the northern lights were really dancing yesterday. Swirling and moving right before your eyes.
Arrived at Schiphol airport for my early morning flight to Tromso to see the Northern Lights.
✅ Looks like flights are resuming tomorrow
✅ 3 nights of clear skies predicted
✅ 3 nights of solar activity predicted
No guarantees on any of those, so🤞
This was last years trip:
✅ Looks like flights are resuming tomorrow
✅ 3 nights of clear skies predicted
✅ 3 nights of solar activity predicted
No guarantees on any of those, so🤞
This was last years trip:
January 7, 2026 at 6:26 PM
Arrived at Schiphol airport for my early morning flight to Tromso to see the Northern Lights.
✅ Looks like flights are resuming tomorrow
✅ 3 nights of clear skies predicted
✅ 3 nights of solar activity predicted
No guarantees on any of those, so🤞
This was last years trip:
✅ Looks like flights are resuming tomorrow
✅ 3 nights of clear skies predicted
✅ 3 nights of solar activity predicted
No guarantees on any of those, so🤞
This was last years trip:
I bought a turntable. Yes… I am that old.
December 6, 2025 at 7:56 PM
I bought a turntable. Yes… I am that old.
2015 was the first year I attended Beyond Tellerrand and I can’t remember a single edition that was not absolutely and completely inspiring. So many fantastic talks and speakers over the years. Such an amazing community.
You should become a friend of the conference. I have.
You should become a friend of the conference. I have.
December 2, 2025 at 8:17 PM
2015 was the first year I attended Beyond Tellerrand and I can’t remember a single edition that was not absolutely and completely inspiring. So many fantastic talks and speakers over the years. Such an amazing community.
You should become a friend of the conference. I have.
You should become a friend of the conference. I have.
After an incredibly busy month of traveling I am finally on my way home. Last trip of the year, now time for rest and family.
Malta was great! Thanks DevFest Malta for having me.
Malta was great! Thanks DevFest Malta for having me.
November 27, 2025 at 5:24 AM
After an incredibly busy month of traveling I am finally on my way home. Last trip of the year, now time for rest and family.
Malta was great! Thanks DevFest Malta for having me.
Malta was great! Thanks DevFest Malta for having me.
Oooh. This is incredibly useful. Just the other day I tried if inherit works in a calc() function - it obviously doesn’t. But now inherit() does!
inherit() is now available to play with in Chrome Canary.
Here's some writing I did about it earlier:
How CSS inherit() Could Simplify Design Systems
www.alwaystwisted.com/articles/mak...
How inherit() Can Simplify Border‑Radius for Components
www.alwaystwisted.com/articles/mak...
🙏🖤
Here's some writing I did about it earlier:
How CSS inherit() Could Simplify Design Systems
www.alwaystwisted.com/articles/mak...
How inherit() Can Simplify Border‑Radius for Components
www.alwaystwisted.com/articles/mak...
🙏🖤
November 25, 2025 at 3:08 PM
Oooh. This is incredibly useful. Just the other day I tried if inherit works in a calc() function - it obviously doesn’t. But now inherit() does!
🔥🔥🔥
Lowest setting. CSS powered flamethrower!
Yes, it is really controlled by CSS. I can add MIDI inputs. Then use CSS to trigger animations and output the result to DMX for controlling the flamethrower.
Lowest setting. CSS powered flamethrower!
Yes, it is really controlled by CSS. I can add MIDI inputs. Then use CSS to trigger animations and output the result to DMX for controlling the flamethrower.
November 18, 2025 at 2:44 PM
🔥🔥🔥
Lowest setting. CSS powered flamethrower!
Yes, it is really controlled by CSS. I can add MIDI inputs. Then use CSS to trigger animations and output the result to DMX for controlling the flamethrower.
Lowest setting. CSS powered flamethrower!
Yes, it is really controlled by CSS. I can add MIDI inputs. Then use CSS to trigger animations and output the result to DMX for controlling the flamethrower.
Current status: working on side projects until the Cloudflare issue has been solved.
November 18, 2025 at 2:21 PM
Current status: working on side projects until the Cloudflare issue has been solved.
DevFest Warsaw is about to start. This is such a lovely space #devfest2025 #devfestwarsaw #googledevelopers
November 15, 2025 at 9:34 AM
DevFest Warsaw is about to start. This is such a lovely space #devfest2025 #devfestwarsaw #googledevelopers
Current mood:
youtu.be/Ra8gSw7Djvo?...
youtu.be/Ra8gSw7Djvo?...
Ren x The Skinner Brothers - Pink Heineken
YouTube video by Ren
youtu.be
November 14, 2025 at 7:31 PM
Current mood:
youtu.be/Ra8gSw7Djvo?...
youtu.be/Ra8gSw7Djvo?...
Arrived in Warsaw this evening for my penultimate conference of the year. Tomorrow DevFest Warsaw, then in a week and a half DevFest Malta.
Tonight a quiet night. We’re halfway November and I have only slept 4 nights in my own bed. I’ll need a couple of months rest after this.
#devfestwarsaw
Tonight a quiet night. We’re halfway November and I have only slept 4 nights in my own bed. I’ll need a couple of months rest after this.
#devfestwarsaw
November 14, 2025 at 5:31 PM
Arrived in Warsaw this evening for my penultimate conference of the year. Tomorrow DevFest Warsaw, then in a week and a half DevFest Malta.
Tonight a quiet night. We’re halfway November and I have only slept 4 nights in my own bed. I’ll need a couple of months rest after this.
#devfestwarsaw
Tonight a quiet night. We’re halfway November and I have only slept 4 nights in my own bed. I’ll need a couple of months rest after this.
#devfestwarsaw
Okay, one more. I just loooooove the reflection here. So good. Doesn’t look like shit at all. No siree, ship it!
November 14, 2025 at 1:16 PM
Okay, one more. I just loooooove the reflection here. So good. Doesn’t look like shit at all. No siree, ship it!
Reposted by Niels Leenheer
Most relatable conference talk silde ever, courtesy of @html5test.com at #HalfStack
November 12, 2025 at 10:19 PM
Most relatable conference talk silde ever, courtesy of @html5test.com at #HalfStack
On my way to Heathrow after another fantastic edition of @halfstackconf.bsky.social.
Happy with how my talk about Baseline went and then I did another unplanned 10 minute talk about one of my side projects that I literally wrote the night before, after the speaker dinner 😅
Happy with how my talk about Baseline went and then I did another unplanned 10 minute talk about one of my side projects that I literally wrote the night before, after the speaker dinner 😅
November 13, 2025 at 9:55 AM
On my way to Heathrow after another fantastic edition of @halfstackconf.bsky.social.
Happy with how my talk about Baseline went and then I did another unplanned 10 minute talk about one of my side projects that I literally wrote the night before, after the speaker dinner 😅
Happy with how my talk about Baseline went and then I did another unplanned 10 minute talk about one of my side projects that I literally wrote the night before, after the speaker dinner 😅
Reposted by Niels Leenheer
It’s alive and on stage! cc: @nerdy.dev
November 12, 2025 at 12:43 PM
It’s alive and on stage! cc: @nerdy.dev
Just got home. First thing my 11-year old said to me: Dad, did you buy a flamethrower…?
Eh. Yes. Yes, I did. 🔥
Eh. Yes. Yes, I did. 🔥
November 8, 2025 at 3:31 PM
Just got home. First thing my 11-year old said to me: Dad, did you buy a flamethrower…?
Eh. Yes. Yes, I did. 🔥
Eh. Yes. Yes, I did. 🔥
Almost home again after a couple of amazing days at @beyondtellerrand.com. Thank you so much @marcthiele.com!
It was so lovely seeing everybody again. After spending a couple hours at home I am off again to London for @halfstackconf.bsky.social and then straight to Warsaw for DevFest.
It was so lovely seeing everybody again. After spending a couple hours at home I am off again to London for @halfstackconf.bsky.social and then straight to Warsaw for DevFest.
November 8, 2025 at 1:58 PM
Almost home again after a couple of amazing days at @beyondtellerrand.com. Thank you so much @marcthiele.com!
It was so lovely seeing everybody again. After spending a couple hours at home I am off again to London for @halfstackconf.bsky.social and then straight to Warsaw for DevFest.
It was so lovely seeing everybody again. After spending a couple hours at home I am off again to London for @halfstackconf.bsky.social and then straight to Warsaw for DevFest.
@nerdy.dev This is happening. MIDI → CSS → DMX → 🔥
November 8, 2025 at 10:03 AM
@nerdy.dev This is happening. MIDI → CSS → DMX → 🔥
Reposted by Niels Leenheer
#js developers 📣! There's still time to sign up for @halfstackconf.bsky.social London on Wed 12th November. There's some great talks on the list, including myself talking about #vectorsearch.
Here's my 10% off code if you still haven't got your 🎫 (😱):
ti.to/halfstack/ha...
See you there! 👋
Here's my 10% off code if you still haven't got your 🎫 (😱):
ti.to/halfstack/ha...
See you there! 👋
November 5, 2025 at 12:31 PM
#js developers 📣! There's still time to sign up for @halfstackconf.bsky.social London on Wed 12th November. There's some great talks on the list, including myself talking about #vectorsearch.
Here's my 10% off code if you still haven't got your 🎫 (😱):
ti.to/halfstack/ha...
See you there! 👋
Here's my 10% off code if you still haven't got your 🎫 (😱):
ti.to/halfstack/ha...
See you there! 👋
Looking for some random thing on AliExpress when suddenly… Hey! I could use a flame thrower! It would be fun to connect it to the web and…
November 5, 2025 at 10:02 AM
Looking for some random thing on AliExpress when suddenly… Hey! I could use a flame thrower! It would be fun to connect it to the web and…
I guess Deutsche Bahn is going to Deutsche Bahn. Good decision to travel the day before. I will be late, but I’ll get to Berlin.
Lessons learned from last year visiting @beyondtellerrand.com where I missed the first two talks and got stranded in the middle of the night on my way back home.
Lessons learned from last year visiting @beyondtellerrand.com where I missed the first two talks and got stranded in the middle of the night on my way back home.
November 5, 2025 at 9:50 AM
I guess Deutsche Bahn is going to Deutsche Bahn. Good decision to travel the day before. I will be late, but I’ll get to Berlin.
Lessons learned from last year visiting @beyondtellerrand.com where I missed the first two talks and got stranded in the middle of the night on my way back home.
Lessons learned from last year visiting @beyondtellerrand.com where I missed the first two talks and got stranded in the middle of the night on my way back home.