Kilian Valkhof
@kilianvalkhof.com
I build tools for devs and designers: @Polypane.app, FixA11y, Superposition | Electron governance member | He/him
Reposted by Kilian Valkhof
so… who's looking for a frontend dev? i'd love to work on/with a robust design system
DMs are now wide open!
DMs are now wide open!
i just want to do good work with other people who want to do good work
December 5, 2025 at 11:57 AM
so… who's looking for a frontend dev? i'd love to work on/with a robust design system
DMs are now wide open!
DMs are now wide open!
Strong +1 on this
December 5, 2025 at 6:22 PM
Strong +1 on this
Reposted by Kilian Valkhof
Coming soon: navigate the elements panel tree using your arrow keys.
The custom-built Polypane elements panel lets you inspect and edit Elements across all viewports in one go.
The custom-built Polypane elements panel lets you inspect and edit Elements across all viewports in one go.
December 5, 2025 at 10:20 AM
Coming soon: navigate the elements panel tree using your arrow keys.
The custom-built Polypane elements panel lets you inspect and edit Elements across all viewports in one go.
The custom-built Polypane elements panel lets you inspect and edit Elements across all viewports in one go.
Reposted by Kilian Valkhof
⚠️ There's only four days left to secure our Black Friday deals ⚠️️
Save £60 on all courses and get yourself a 50% discount coupon that you can use at any time.
Deals end December 9!
piccalilli.link/black-friday...
Save £60 on all courses and get yourself a 50% discount coupon that you can use at any time.
Deals end December 9!
piccalilli.link/black-friday...
Black Friday Deals
piccalilli.link
December 5, 2025 at 9:25 AM
⚠️ There's only four days left to secure our Black Friday deals ⚠️️
Save £60 on all courses and get yourself a 50% discount coupon that you can use at any time.
Deals end December 9!
piccalilli.link/black-friday...
Save £60 on all courses and get yourself a 50% discount coupon that you can use at any time.
Deals end December 9!
piccalilli.link/black-friday...
it's fine who needs the majority of the internet anyway
December 5, 2025 at 9:10 AM
it's fine who needs the majority of the internet anyway
Happy Sinterklaas for all who celebrate.
It's customary to give gifts on this day, and my HTMHell Advent Calendar article is live! Join me to learn about IDREFs.
htmhell.dev/adventcalend...
It's customary to give gifts on this day, and my HTMHell Advent Calendar article is live! Join me to learn about IDREFs.
htmhell.dev/adventcalend...
IDREFs: What they are and how to use them - HTMHell
A collection of bad practices in HTML, copied from real websites.
htmhell.dev
December 5, 2025 at 9:07 AM
Happy Sinterklaas for all who celebrate.
It's customary to give gifts on this day, and my HTMHell Advent Calendar article is live! Join me to learn about IDREFs.
htmhell.dev/adventcalend...
It's customary to give gifts on this day, and my HTMHell Advent Calendar article is live! Join me to learn about IDREFs.
htmhell.dev/adventcalend...
tad aggressive there, Firefox.
December 4, 2025 at 11:51 AM
tad aggressive there, Firefox.
Reposted by Kilian Valkhof
Let's enjoy a varied collection of very good links in The Index #147 to get us through the Wednesday hump.
piccalil.li/the-index/147/
piccalil.li/the-index/147/
The Index: Issue #147
Let's enjoy a varied collection of very good links in The Index #147 to get us through the Wednesday hump.
piccalil.li
December 3, 2025 at 12:07 PM
Let's enjoy a varied collection of very good links in The Index #147 to get us through the Wednesday hump.
piccalil.li/the-index/147/
piccalil.li/the-index/147/
Reposted by Kilian Valkhof
Today is the LAST DAY of my Black Friday sale! ⌛️
If you've been thinking about grabbing access to the Practical Accessibility course, now's the time to do it 👇🏻
30% off expires tomorrow: practical-accessibility.today
If you've been thinking about grabbing access to the Practical Accessibility course, now's the time to do it 👇🏻
30% off expires tomorrow: practical-accessibility.today
📣 Hear hear! The biggest savings on the Practical Accessibility course start *today*—for a limited time only.
Starting today, you can get the course for 30% off — that's $279 instead of $399. The discounted price excludes sales tax that may be applied depending on where you are buying from.
Starting today, you can get the course for 30% off — that's $279 instead of $399. The discounted price excludes sales tax that may be applied depending on where you are buying from.
The Practical Accessibility Course
A get-right-down-to-it online course for Web designers and developers who want to start creating more accessible Web user interfaces and digital products today
practical-accessibility.today
December 3, 2025 at 7:21 AM
Today is the LAST DAY of my Black Friday sale! ⌛️
If you've been thinking about grabbing access to the Practical Accessibility course, now's the time to do it 👇🏻
30% off expires tomorrow: practical-accessibility.today
If you've been thinking about grabbing access to the Practical Accessibility course, now's the time to do it 👇🏻
30% off expires tomorrow: practical-accessibility.today
Some people, when confronted with a problem, think “I know, I’ll use virtualization.”
Now they have two problems.
Now they have two problems.
December 3, 2025 at 9:34 AM
Some people, when confronted with a problem, think “I know, I’ll use virtualization.”
Now they have two problems.
Now they have two problems.
@cassidoo.co heya! Confirming my email for your newsletter sends me to cassidoo.co/newsletter/c... which is a 404.
cassidoo.co
December 3, 2025 at 9:33 AM
@cassidoo.co heya! Confirming my email for your newsletter sends me to cassidoo.co/newsletter/c... which is a 404.
Reposted by Kilian Valkhof
🚨Final Call🚨
The Polypane Black Friday deal ends in a few hours.
If you want to build better websites faster (and save money doing it), this is your moment.
22% off. Ends today.
👉 polypane.app/black-friday/
The Polypane Black Friday deal ends in a few hours.
If you want to build better websites faster (and save money doing it), this is your moment.
22% off. Ends today.
👉 polypane.app/black-friday/
Polypane Black Friday | Polypane
Get the browser for devs who care for 22% during our Black Friday sale. Available until December 1st.
polypane.app
December 1, 2025 at 8:23 PM
🚨Final Call🚨
The Polypane Black Friday deal ends in a few hours.
If you want to build better websites faster (and save money doing it), this is your moment.
22% off. Ends today.
👉 polypane.app/black-friday/
The Polypane Black Friday deal ends in a few hours.
If you want to build better websites faster (and save money doing it), this is your moment.
22% off. Ends today.
👉 polypane.app/black-friday/
Reposted by Kilian Valkhof
*Last day.*
The Black Friday sale ends tonight.
Get *22% off Polypane* (Lifetime discount on yearly plans).
Go go go! 🏃 polypane.app/black-friday/
The Black Friday sale ends tonight.
Get *22% off Polypane* (Lifetime discount on yearly plans).
Go go go! 🏃 polypane.app/black-friday/
Polypane Black Friday | Polypane
Get the browser for devs who care for 22% during our Black Friday sale. Available until December 1st.
polypane.app
December 1, 2025 at 9:12 AM
*Last day.*
The Black Friday sale ends tonight.
Get *22% off Polypane* (Lifetime discount on yearly plans).
Go go go! 🏃 polypane.app/black-friday/
The Black Friday sale ends tonight.
Get *22% off Polypane* (Lifetime discount on yearly plans).
Go go go! 🏃 polypane.app/black-friday/
Reposted by Kilian Valkhof
It's December 1st, which means that throughout the entire month you should reserve 5-10 minutes every day to read a fantastic article about HTML. ❤️🔥
Check out what's hidden behind the first door.
htmhell.dev/adventcalendar
Check out what's hidden behind the first door.
htmhell.dev/adventcalendar
December 1, 2025 at 7:48 AM
It's December 1st, which means that throughout the entire month you should reserve 5-10 minutes every day to read a fantastic article about HTML. ❤️🔥
Check out what's hidden behind the first door.
htmhell.dev/adventcalendar
Check out what's hidden behind the first door.
htmhell.dev/adventcalendar
Reposted by Kilian Valkhof
Tomorrow's the last day!
After 7 years of selling courses, I'm finally doing a Black Friday sale.
I'd held off for from doing sales in general for all this time, but had some smart people get me on board with it, so I figured if I'm going to do it, I'll go big:
40% off + Flexbox Simplified for free.
I'd held off for from doing sales in general for all this time, but had some smart people get me on board with it, so I figured if I'm going to do it, I'll go big:
40% off + Flexbox Simplified for free.
November 30, 2025 at 3:40 PM
Tomorrow's the last day!
Reposted by Kilian Valkhof
Weekend project? 🛠️
Make sure your site looks great on every screen size.
Polypane shows you mobile, tablet, and desktop viewports side-by-side. Fix a bug in one, see it fixed in all.
Grab our Friday deal this weekend:
👉 polypane.app/black-friday/
Make sure your site looks great on every screen size.
Polypane shows you mobile, tablet, and desktop viewports side-by-side. Fix a bug in one, see it fixed in all.
Grab our Friday deal this weekend:
👉 polypane.app/black-friday/
Polypane Black Friday | Polypane
Get the browser for devs who care for 22% during our Black Friday sale. Available until December 1st.
polypane.app
November 30, 2025 at 1:39 PM
Weekend project? 🛠️
Make sure your site looks great on every screen size.
Polypane shows you mobile, tablet, and desktop viewports side-by-side. Fix a bug in one, see it fixed in all.
Grab our Friday deal this weekend:
👉 polypane.app/black-friday/
Make sure your site looks great on every screen size.
Polypane shows you mobile, tablet, and desktop viewports side-by-side. Fix a bug in one, see it fixed in all.
Grab our Friday deal this weekend:
👉 polypane.app/black-friday/
3 more waiting to be released but who's keeping count.
110.
That’s the number of user requests we implemented in 2025 (...I might have gotten nerd-sniped into a few of them 😅).
Polypane is built *with* and *for* our community. Join us today for 22% off 👉 polypane.app/black-friday/
That’s the number of user requests we implemented in 2025 (...I might have gotten nerd-sniped into a few of them 😅).
Polypane is built *with* and *for* our community. Join us today for 22% off 👉 polypane.app/black-friday/
Polypane Black Friday | Polypane
Get the browser for devs who care for 22% during our Black Friday sale. Available until December 1st.
polypane.app
November 29, 2025 at 9:58 AM
3 more waiting to be released but who's keeping count.
Reposted by Kilian Valkhof
This is one of my favorite traditions that we do on Electron; it’s a great time to both recharge and get caught up on internal maintenance and projects that we might not normally have the time to look into
☃️ As the end of the year draws near, the Electron project will be taking its usual quiet period for December.
Read more on our blog: www.electronjs.org/blog/dec-qui...
Read more on our blog: www.electronjs.org/blog/dec-qui...
December Quiet Month (Dec'25) | Electron
Starting December 1, the Electron project will enter a quiet period before picking back up at full capacity in January 2026. For full details, see the Policies section below.
www.electronjs.org
November 29, 2025 at 5:57 AM
This is one of my favorite traditions that we do on Electron; it’s a great time to both recharge and get caught up on internal maintenance and projects that we might not normally have the time to look into
Reposted by Kilian Valkhof
It's that time of year again! Let's have a look at the deals we, and our much loved community are offering this year. It's the most important time of year for independents, so let's give them our support 💛
piccalil.li/links/black-...
piccalil.li/links/black-...
Black Friday deals 2025
It's that time of year again! Let's have a look at the deals we, and our much loved community are offering this year. It's the most important time of year for independents, so let's give them our support...
piccalil.li
November 28, 2025 at 12:08 PM
It's that time of year again! Let's have a look at the deals we, and our much loved community are offering this year. It's the most important time of year for independents, so let's give them our support 💛
piccalil.li/links/black-...
piccalil.li/links/black-...
clones.
it's clones.
it's clones.
Polypane is a must have in my toolbox as well. But what I value even more is that customer service and experience is totally out of this world. I have no clue how @kilianvalkhof.com is doing this while constantly bringing up new versions and ideas, but I fcking love it.
When you don’t code often, it’s easy to forget how useful @polypane.app is for web development. It highlights issues that might get overlooked on a first pass, and it makes testing and debugging a piece of cake. Forever grateful for your effort, @kilianvalkhof.com!
November 28, 2025 at 12:13 PM
clones.
it's clones.
it's clones.
Reposted by Kilian Valkhof
It's Black Friday! 🏷️
We released *18 versions* and *42 new major features* in 2025 alone.
From video recording to advanced emulation, Polypane is the most powerful tool for web developers.
Get your *22% lifetime discount* today:
👉 polypane.app/black-friday/
We released *18 versions* and *42 new major features* in 2025 alone.
From video recording to advanced emulation, Polypane is the most powerful tool for web developers.
Get your *22% lifetime discount* today:
👉 polypane.app/black-friday/
Polypane Black Friday | Polypane
Get the browser for devs who care for 22% during our Black Friday sale. Available until December 1st.
polypane.app
November 28, 2025 at 10:11 AM
It's Black Friday! 🏷️
We released *18 versions* and *42 new major features* in 2025 alone.
From video recording to advanced emulation, Polypane is the most powerful tool for web developers.
Get your *22% lifetime discount* today:
👉 polypane.app/black-friday/
We released *18 versions* and *42 new major features* in 2025 alone.
From video recording to advanced emulation, Polypane is the most powerful tool for web developers.
Get your *22% lifetime discount* today:
👉 polypane.app/black-friday/
This is an amazing deal for a world-class course that I recommend to anyone working on the web.
[1/2] Oh. A PSA for everyone who has a @polypane.app subscription:
You already get a special discount on the Practical Accessibility course for being a Polypane user. You should be able to find the discount when you log in using your account.
Discounts are cumulative during this Black Friday...
You already get a special discount on the Practical Accessibility course for being a Polypane user. You should be able to find the discount when you log in using your account.
Discounts are cumulative during this Black Friday...
November 27, 2025 at 3:44 PM
This is an amazing deal for a world-class course that I recommend to anyone working on the web.
Reposted by Kilian Valkhof
[1/2] Oh. A PSA for everyone who has a @polypane.app subscription:
You already get a special discount on the Practical Accessibility course for being a Polypane user. You should be able to find the discount when you log in using your account.
Discounts are cumulative during this Black Friday...
You already get a special discount on the Practical Accessibility course for being a Polypane user. You should be able to find the discount when you log in using your account.
Discounts are cumulative during this Black Friday...
November 27, 2025 at 3:35 PM
[1/2] Oh. A PSA for everyone who has a @polypane.app subscription:
You already get a special discount on the Practical Accessibility course for being a Polypane user. You should be able to find the discount when you log in using your account.
Discounts are cumulative during this Black Friday...
You already get a special discount on the Practical Accessibility course for being a Polypane user. You should be able to find the discount when you log in using your account.
Discounts are cumulative during this Black Friday...
I’m at DevFest Strasbourg today! My talk is at 15:40 on stage 1.
I brought stickers, so come say hi!
I brought stickers, so come say hi!
November 27, 2025 at 9:10 AM
I’m at DevFest Strasbourg today! My talk is at 15:40 on stage 1.
I brought stickers, so come say hi!
I brought stickers, so come say hi!
Reposted by Kilian Valkhof
Several new goodies in the CSS-Tricks Almanac this morning:
🔸 corner-shape
css-tricks.com/almanac/prop...
🔸 ::picker-icon
css-tricks.com/almanac/pseu...
🔸 :target-before/after
css-tricks.com/almanac/pseu...
css-tricks.com/almanac/pseu...
🔸 corner-shape
css-tricks.com/almanac/prop...
🔸 ::picker-icon
css-tricks.com/almanac/pseu...
🔸 :target-before/after
css-tricks.com/almanac/pseu...
css-tricks.com/almanac/pseu...
::picker-icon | CSS-Tricks
The ::picker-icon pseudo-element allows us to style the dropdown icon of a <select> element.
css-tricks.com
November 26, 2025 at 2:32 PM
Several new goodies in the CSS-Tricks Almanac this morning:
🔸 corner-shape
css-tricks.com/almanac/prop...
🔸 ::picker-icon
css-tricks.com/almanac/pseu...
🔸 :target-before/after
css-tricks.com/almanac/pseu...
css-tricks.com/almanac/pseu...
🔸 corner-shape
css-tricks.com/almanac/prop...
🔸 ::picker-icon
css-tricks.com/almanac/pseu...
🔸 :target-before/after
css-tricks.com/almanac/pseu...
css-tricks.com/almanac/pseu...