Jan van Hellemond
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jvhellemond.nl
Jan van Hellemond
@jvhellemond.nl
Man who sold the world and is currently chasing payment.
I bought another domain name:
doesthetrumpphoneexistyet.com

If the yanks fasc would still let me into the country for that, they certainly won't after this toot 😌

/ht @dompreston.com
Does the Trump phone exist yet?
No, it does not.
doesTheTrumpPhoneExistYet.com
December 12, 2025 at 6:36 PM
Reposted by Jan van Hellemond
performance.now() is coming!

The night before the conference, 29th of October, @mozilla.org organises performance.sync(), the pre-meetup where you can meet your peers to mentally prepare for two days of information overload. They're also looking for a few people to present.
luma.com/ziykhh4y
performance.sync() 2025 · Luma
performance.sync() is a meet-up taking place on the evening before the performance.now on Wednesday October 29th! We are looking for speakers! Submit your…
luma.com
September 1, 2025 at 12:56 PM
Reposted by Jan van Hellemond
performance.now() is coming!

@adevnadia.bsky.social will provide a deep dive into the new React Server Components. How does the app render in the browser? What are their performance implications? How do they compare to traditional SSR and CSR techniques?

perfnow.nl/speakers.htm...
performance.now(); 30th and 31st of October, Amsterdam
On 30th and 31st of October, 2025, the sixth edition of performance.now() will take place in Amsterdam—a single track conference, covering today’s most important web performance insights.
perfnow.nl
September 2, 2025 at 11:27 AM
August 30, 2025 at 4:34 PM
Not knowing about Greek mythology is my Achilles' horse.
www.reddit.com/r/meirl/comm...
meow
you, me, us, irl, reddit style
www.reddit.com
March 30, 2025 at 1:22 PM
TIL multipart/mixed HTTP requests can be faked in #JavaScript (well, fetch) by:
- Creating a FormData object with an entry named "file";
- Creating a request without a content type header;
- Setting the FormData object as the request body;
- ...

1/2
March 25, 2025 at 1:20 PM
For the benefit of any Americans here: en.wikipedia.org/wiki/Other_P...
Other People - Wikipedia
en.wikipedia.org
March 4, 2025 at 7:50 AM
#CSS' text-box-trim is a game changer. That is all.
March 1, 2025 at 1:09 PM
If there is anything I have learned in all my years, decades even, of writing #JavaScript, it is that undefined is not a function.
February 27, 2025 at 9:34 AM
I just typed this #JS:

`path.to.object.optionalMethod?.();`

Optionally chaining a function call. Nice, but I need to get used to that syntax 😅
February 26, 2025 at 9:43 AM
Reposted by Jan van Hellemond
Earlier today #cssday 2025 ticket sales opened. The going is brisk; early birds will likely sell out today.

cssday.nl/tickets.html
CSS Day 2025, 5th & 6th of June, Amsterdam
CSS Day is the conference for CSS designers, developers, spec writers, and browser vendors.
cssday.nl
February 11, 2025 at 10:53 AM
Hey gurl, what's your XPathResult.resultType? 😻
January 31, 2025 at 11:20 AM
So I follow @joost.blog on here for a bit of drama, but jeez… 😅
January 12, 2025 at 12:29 PM
December 25, 2024 at 10:09 PM
TIL that pattern validation does not work for
English 300