Frank van Puffelen
@puf.io
People + Tech = 🎉
🇳🇱 NL born, 🌁 SF based
Currently: FlutterFlow 💜
Previously: Firebase & Flutter @ Google 🔥💙
🇳🇱 NL born, 🌁 SF based
Currently: FlutterFlow 💜
Previously: Firebase & Flutter @ Google 🔥💙
For a recent article I wrote an intro that was a bit longer than I aimed for, so I wanted to make it collapsible. It turns out the <details> tag does precisely that, no JS needed.
HTML is the gift that keeps on giving.
HTML is the gift that keeps on giving.
<details>: The Details disclosure element - HTML | MDN
The <details> HTML element creates a disclosure widget in which information is visible only when the widget is toggled into an open state. A summary or label must be provided using the <summary> element.
developer.mozilla.org
January 21, 2026 at 2:51 AM
For a recent article I wrote an intro that was a bit longer than I aimed for, so I wanted to make it collapsible. It turns out the <details> tag does precisely that, no JS needed.
HTML is the gift that keeps on giving.
HTML is the gift that keeps on giving.
Reposted by Frank van Puffelen
It's so weird that a lot of people think the quality of software is measured in how often it gets updated—it's literally the opposite.
January 19, 2026 at 4:37 PM
It's so weird that a lot of people think the quality of software is measured in how often it gets updated—it's literally the opposite.
Just finished reading The Amazing Maurice and His Educated Rodents by Terry Pratchett. Rats gain sentience via magical waste. A cat joins them. Chaos and moral dilemmas ensue. 🐀🐈⬛🪈
This is Pratchet's first YA book in Discworld, and won the Carnegie Medal in 2001.
⬇️🧵
1/2
This is Pratchet's first YA book in Discworld, and won the Carnegie Medal in 2001.
⬇️🧵
1/2
January 19, 2026 at 3:23 PM
Just finished reading The Amazing Maurice and His Educated Rodents by Terry Pratchett. Rats gain sentience via magical waste. A cat joins them. Chaos and moral dilemmas ensue. 🐀🐈⬛🪈
This is Pratchet's first YA book in Discworld, and won the Carnegie Medal in 2001.
⬇️🧵
1/2
This is Pratchet's first YA book in Discworld, and won the Carnegie Medal in 2001.
⬇️🧵
1/2
Reposted by Frank van Puffelen
Today is National Thesaurus Day.
Personally, we find these made-up holidays contemptible, abhorrent, nauseating, repugnant, and unpalatable.
Personally, we find these made-up holidays contemptible, abhorrent, nauseating, repugnant, and unpalatable.
January 18, 2026 at 3:03 PM
Today is National Thesaurus Day.
Personally, we find these made-up holidays contemptible, abhorrent, nauseating, repugnant, and unpalatable.
Personally, we find these made-up holidays contemptible, abhorrent, nauseating, repugnant, and unpalatable.
📖🛩️ I just read Skunk Works by Ben Rich - a memoir full of surprising detail on the development of secret aircraft like the U-2, SR-71, and F-117. Great insight into how Skunk Works operated from the '40s to early '90s.
Rating: ★★★★☆
Review: puf.io/books/skunk-w...
Rating: ★★★★☆
Review: puf.io/books/skunk-w...
January 18, 2026 at 11:53 PM
📖🛩️ I just read Skunk Works by Ben Rich - a memoir full of surprising detail on the development of secret aircraft like the U-2, SR-71, and F-117. Great insight into how Skunk Works operated from the '40s to early '90s.
Rating: ★★★★☆
Review: puf.io/books/skunk-w...
Rating: ★★★★☆
Review: puf.io/books/skunk-w...
🚲⚡️ The New Wheel electric bike shop is opening a new location on 1031 Valencia street in San Francisco's Mission district. The service center opens January 12, and the retail store will open its door on February 2nd.
More: puf.io/socials/2026-...
More: puf.io/socials/2026-...
January 18, 2026 at 3:26 PM
🚲⚡️ The New Wheel electric bike shop is opening a new location on 1031 Valencia street in San Francisco's Mission district. The service center opens January 12, and the retail store will open its door on February 2nd.
More: puf.io/socials/2026-...
More: puf.io/socials/2026-...
Tompkins Stairway is a colorful, tiled stairway about a block from the Alemany Farmer's market on the easter edge of Bernal Heights. Opened in 2019, it's yet another beautiful destination in San Francisco if you want to get your steps/stairs in!
More: puf.io/socials/2025-...
More: puf.io/socials/2025-...
January 18, 2026 at 2:33 AM
Tompkins Stairway is a colorful, tiled stairway about a block from the Alemany Farmer's market on the easter edge of Bernal Heights. Opened in 2019, it's yet another beautiful destination in San Francisco if you want to get your steps/stairs in!
More: puf.io/socials/2025-...
More: puf.io/socials/2025-...
📚🪄🧬 What if Terry Pratchett wrote a science textbook?
The Science of Discworld series blends Discworld fiction with real-world science, alternating between wizardly mischief (by Pratchett) and popular science explainers (by Ian Stewart and Jack Cohen).
More ⬇️ in 🧵
1/3
The Science of Discworld series blends Discworld fiction with real-world science, alternating between wizardly mischief (by Pratchett) and popular science explainers (by Ian Stewart and Jack Cohen).
More ⬇️ in 🧵
1/3
January 17, 2026 at 8:28 PM
📚🪄🧬 What if Terry Pratchett wrote a science textbook?
The Science of Discworld series blends Discworld fiction with real-world science, alternating between wizardly mischief (by Pratchett) and popular science explainers (by Ian Stewart and Jack Cohen).
More ⬇️ in 🧵
1/3
The Science of Discworld series blends Discworld fiction with real-world science, alternating between wizardly mischief (by Pratchett) and popular science explainers (by Ian Stewart and Jack Cohen).
More ⬇️ in 🧵
1/3
"Effective enterprises delegate decision making to the lowest level possible, because obviously decisions should be made by the people most closely involved in the work. Management is there as a tie breaker." - Gordon Moore
January 16, 2026 at 11:49 PM
"Effective enterprises delegate decision making to the lowest level possible, because obviously decisions should be made by the people most closely involved in the work. Management is there as a tie breaker." - Gordon Moore
I am used to sharing my "Read" list from GoodReads with folks, even when they're not on GoodReads themselves. But somehow the link now required you to be signed in. Is that new? Or am I doing it wrong?
Example:
Example:
Sign in
See what your friends are reading
www.goodreads.com
January 16, 2026 at 4:57 PM
I am used to sharing my "Read" list from GoodReads with folks, even when they're not on GoodReads themselves. But somehow the link now required you to be signed in. Is that new? Or am I doing it wrong?
Example:
Example:
Reposted by Frank van Puffelen
We are joining Cloudflare! astro.build/blog/joining...
The Astro Technology Company joins Cloudflare | Astro
The Astro Technology Company is joining Cloudflare! Astro remains open-source, MIT-licensed, and platform-agnostic. With Cloudflare's support, we're focusing 100% on building the best framework for…
astro.build
January 16, 2026 at 2:17 PM
We are joining Cloudflare! astro.build/blog/joining...
Just finished Network Effect by Martha Wells — Book 5 in The Murderbot Diaries.
This series follows a self-aware security robot navigating freedom, identity, and awkward human feelings.
PS: The first book is being adapted into a show on Apple TV!
More 👇 in 🧵
1/3
This series follows a self-aware security robot navigating freedom, identity, and awkward human feelings.
PS: The first book is being adapted into a show on Apple TV!
More 👇 in 🧵
1/3
January 16, 2026 at 2:37 AM
Just finished Network Effect by Martha Wells — Book 5 in The Murderbot Diaries.
This series follows a self-aware security robot navigating freedom, identity, and awkward human feelings.
PS: The first book is being adapted into a show on Apple TV!
More 👇 in 🧵
1/3
This series follows a self-aware security robot navigating freedom, identity, and awkward human feelings.
PS: The first book is being adapted into a show on Apple TV!
More 👇 in 🧵
1/3
Reposted by Frank van Puffelen
wikipedia turns 25 today! the last unenshittified major website! backbone of online info! triumph of humanity! powered by urge of unpaid randos to correct each other! somehow mostly reliable! "good thing wikipedia works in practice, because it sure doesn't work in theory" - old wiki adage
January 15, 2026 at 1:47 PM
wikipedia turns 25 today! the last unenshittified major website! backbone of online info! triumph of humanity! powered by urge of unpaid randos to correct each other! somehow mostly reliable! "good thing wikipedia works in practice, because it sure doesn't work in theory" - old wiki adage
🏜️🦈 Large sculptures keep appearing at more places in San Francisco, and I love it! 😍
This is Desert Shark, originally made for Burning Man in 2022, but just now landed at Pier 45 on Embarcadero, right in from of Musée Mécanique.
More on: puf.io/socials/2025-...
This is Desert Shark, originally made for Burning Man in 2022, but just now landed at Pier 45 on Embarcadero, right in from of Musée Mécanique.
More on: puf.io/socials/2025-...
January 14, 2026 at 11:59 PM
🏜️🦈 Large sculptures keep appearing at more places in San Francisco, and I love it! 😍
This is Desert Shark, originally made for Burning Man in 2022, but just now landed at Pier 45 on Embarcadero, right in from of Musée Mécanique.
More on: puf.io/socials/2025-...
This is Desert Shark, originally made for Burning Man in 2022, but just now landed at Pier 45 on Embarcadero, right in from of Musée Mécanique.
More on: puf.io/socials/2025-...
I use an LLM differently in cases where I know "nothing" [1] vs cases where I know "everything" [2].
On [1] I check LLM output against my expectations and catch hallucinations with a chuckle/shrug.
On [2] I stick to questions where LLM training data is large and in agreement.
On [1] I check LLM output against my expectations and catch hallucinations with a chuckle/shrug.
On [2] I stick to questions where LLM training data is large and in agreement.
January 13, 2026 at 5:39 PM
I use an LLM differently in cases where I know "nothing" [1] vs cases where I know "everything" [2].
On [1] I check LLM output against my expectations and catch hallucinations with a chuckle/shrug.
On [2] I stick to questions where LLM training data is large and in agreement.
On [1] I check LLM output against my expectations and catch hallucinations with a chuckle/shrug.
On [2] I stick to questions where LLM training data is large and in agreement.
Developer Relations events work often feels intuition-driven: we choose our talks, swag, community, content based on feeling and experience. But you can bring structure to it using the same tool marketers rely on: the adoption funnel.
Read more about it ⬇️🧵
1/3
Read more about it ⬇️🧵
1/3
January 12, 2026 at 5:43 PM
Developer Relations events work often feels intuition-driven: we choose our talks, swag, community, content based on feeling and experience. But you can bring structure to it using the same tool marketers rely on: the adoption funnel.
Read more about it ⬇️🧵
1/3
Read more about it ⬇️🧵
1/3
🚲⚡️ The New Wheel electric bike shop is opening a new location on 1031 Valencia street in San Francisco's Mission district. The service center opens January 12, and the retail store will open its door on February 2nd.
More: puf.io/socials/2026-...
More: puf.io/socials/2026-...
January 10, 2026 at 6:18 PM
🚲⚡️ The New Wheel electric bike shop is opening a new location on 1031 Valencia street in San Francisco's Mission district. The service center opens January 12, and the retail store will open its door on February 2nd.
More: puf.io/socials/2026-...
More: puf.io/socials/2026-...
📚🪄🧬 What if Terry Pratchett wrote a science textbook?
The Science of Discworld series blends Discworld fiction with real-world science, alternating between wizardly mischief (by Pratchett) and popular science explainers (by Ian Stewart and Jack Cohen).
More ⬇️ in 🧵
1/3
The Science of Discworld series blends Discworld fiction with real-world science, alternating between wizardly mischief (by Pratchett) and popular science explainers (by Ian Stewart and Jack Cohen).
More ⬇️ in 🧵
1/3
January 10, 2026 at 2:59 AM
📚🪄🧬 What if Terry Pratchett wrote a science textbook?
The Science of Discworld series blends Discworld fiction with real-world science, alternating between wizardly mischief (by Pratchett) and popular science explainers (by Ian Stewart and Jack Cohen).
More ⬇️ in 🧵
1/3
The Science of Discworld series blends Discworld fiction with real-world science, alternating between wizardly mischief (by Pratchett) and popular science explainers (by Ian Stewart and Jack Cohen).
More ⬇️ in 🧵
1/3
📖 🇳🇱 🏠 The Dutch House is an interesting fictional, historic drama. Loved the first half, but the second half dragged with too much reflection. Solid narration by Tom Hanks - fitting, not flashy.
★★★☆☆
Full review: puf.io/books/the-dut...
★★★☆☆
Full review: puf.io/books/the-dut...
January 8, 2026 at 11:50 PM
📖 🇳🇱 🏠 The Dutch House is an interesting fictional, historic drama. Loved the first half, but the second half dragged with too much reflection. Solid narration by Tom Hanks - fitting, not flashy.
★★★☆☆
Full review: puf.io/books/the-dut...
★★★☆☆
Full review: puf.io/books/the-dut...
I usually ask ChatGPT or Gemini to check my book reviews. My current prompt for this:
> Check my review for factual and grammatical/syntactical accuracy.
> Provide feedback in bullet points instead of a full rewrite.
> As always: don't suggest emdashes (seriously!)
📖✏️🤖🧠
> Check my review for factual and grammatical/syntactical accuracy.
> Provide feedback in bullet points instead of a full rewrite.
> As always: don't suggest emdashes (seriously!)
📖✏️🤖🧠
January 8, 2026 at 7:07 PM
I usually ask ChatGPT or Gemini to check my book reviews. My current prompt for this:
> Check my review for factual and grammatical/syntactical accuracy.
> Provide feedback in bullet points instead of a full rewrite.
> As always: don't suggest emdashes (seriously!)
📖✏️🤖🧠
> Check my review for factual and grammatical/syntactical accuracy.
> Provide feedback in bullet points instead of a full rewrite.
> As always: don't suggest emdashes (seriously!)
📖✏️🤖🧠
Reposted by Frank van Puffelen
Actually we don't have to guess. It's definitely about the nonconsensual images. And also the trolley problem for some reason
January 8, 2026 at 4:21 PM
Actually we don't have to guess. It's definitely about the nonconsensual images. And also the trolley problem for some reason
📍🗺️ Geoqueries on Firestore used to mean geohashes and 5.4x read overhead. 💸
With multi-field inequalities, you can now drop that overhead to ~1.3x. But there's a catch: you now pay for index scans. Those *are* much cheaper, but... details 👇
puf.io/posts/how-to-...
With multi-field inequalities, you can now drop that overhead to ~1.3x. But there's a catch: you now pay for index scans. Those *are* much cheaper, but... details 👇
puf.io/posts/how-to-...
January 7, 2026 at 4:10 PM
📍🗺️ Geoqueries on Firestore used to mean geohashes and 5.4x read overhead. 💸
With multi-field inequalities, you can now drop that overhead to ~1.3x. But there's a catch: you now pay for index scans. Those *are* much cheaper, but... details 👇
puf.io/posts/how-to-...
With multi-field inequalities, you can now drop that overhead to ~1.3x. But there's a catch: you now pay for index scans. Those *are* much cheaper, but... details 👇
puf.io/posts/how-to-...
Just finished Network Effect by Martha Wells — Book 5 in The Murderbot Diaries.
This series follows a self-aware security robot navigating freedom, identity, and awkward human feelings.
PS: The first book is being adapted into a show on Apple TV!
More 👇 in 🧵
1/3
This series follows a self-aware security robot navigating freedom, identity, and awkward human feelings.
PS: The first book is being adapted into a show on Apple TV!
More 👇 in 🧵
1/3
January 6, 2026 at 11:15 PM
Just finished Network Effect by Martha Wells — Book 5 in The Murderbot Diaries.
This series follows a self-aware security robot navigating freedom, identity, and awkward human feelings.
PS: The first book is being adapted into a show on Apple TV!
More 👇 in 🧵
1/3
This series follows a self-aware security robot navigating freedom, identity, and awkward human feelings.
PS: The first book is being adapted into a show on Apple TV!
More 👇 in 🧵
1/3
📚 I finished Armageddon (my 13th book in the Awaken Online universe). A VR game world ruled by AI, now bringing all major arcs together in one huge showdown. Still a page-turner, but it’s feeling a bit too Marvel now - epic fights, less plot.
Rating and links 👇
1/2
Rating and links 👇
1/2
January 4, 2026 at 7:09 PM
📚 I finished Armageddon (my 13th book in the Awaken Online universe). A VR game world ruled by AI, now bringing all major arcs together in one huge showdown. Still a page-turner, but it’s feeling a bit too Marvel now - epic fights, less plot.
Rating and links 👇
1/2
Rating and links 👇
1/2
📕🧑💻 This Is for Everyone by Tim Berners-Lee is a fascinating origin story by the inventor or the web, but I wished for more tech, and less ceremony. Still, a meaningful read for anyone in tech.
Rating: 3 out of 5 stars
★★★☆☆
Full review: puf.io/books/this-is...
Rating: 3 out of 5 stars
★★★☆☆
Full review: puf.io/books/this-is...
January 4, 2026 at 2:46 AM
📕🧑💻 This Is for Everyone by Tim Berners-Lee is a fascinating origin story by the inventor or the web, but I wished for more tech, and less ceremony. Still, a meaningful read for anyone in tech.
Rating: 3 out of 5 stars
★★★☆☆
Full review: puf.io/books/this-is...
Rating: 3 out of 5 stars
★★★☆☆
Full review: puf.io/books/this-is...