Seen – Virtual list rendering with 1M+ notes
Edit: Thank you so much for taking a look at Seen! Yes, I know, it's really slow. And scrolling does not render notes instantly. And the title is a bit clickbait-y. I'll try my best to improve on it though. This is just a preview, the most basic version of Seen, and it's getting there. But, oh God, I almost got a heart attack when I opened up Vercel Analytics and saw ~1,500 page views, up from 10 or 12. Thank you again! It's such a weird experience showing something to the world for the first time as a 16-year-old and seeing so many people look at it. Hello HN! I've been working on creating…
In plain words
Seen is a note-taking app that demonstrates virtual list rendering to handle over one million notes in a masonry layout while minimizing CPU and memory usage. It includes client-side search and basic note creation, editing, and deletion capabilities. The application is in early preview stage, with the developer acknowledging current performance limitations and planning improvements.
written from the facts on this page · September 2026
From the sources
In the maker’s words, at launch
Edit: Thank you so much for taking a look at Seen! Yes, I know, it's really slow. And scrolling does not render notes instantly. And the title is a bit clickbait-y. I'll try my best to improve on it though. This is just a preview, the most basic version of Seen, and it's getting there. But, oh God, I almost got a heart attack when I opened up Vercel Analytics and saw ~1,500 page views, up from 10 or 12. Thank you again! It's such a weird experience showing something to the world for the first time as a 16-year-old and seeing so many people look at it. Hello HN! I've been working on creating a new note-taking app called Seen. Right now, it's really just a preview: virtual-list rendering ~1,000,000 notes in a masonry layout, while trying to minimize CPU and memory usage as much as possible. Seen currently has: - A client-side search feature - Creating, updating, deleting the topmost note (locally; no changes are saved to any server) - Automatic repacking of the masonry layout when the window width changes - A lot of bugs, I'm sure I reached a point where I thought I was ready to show the Seen to the world, and this is it. It's pretty basic, I know, but I'm really proud of it. Seen was born out of an experiment to see just how fast things can become if you use the right techniques, and will (hopefully) achieve this dream sometime in the near future. My vision for Seen is to create something that can handle a lot of notes while using the least amount of resources. If you've got any suggestions or bugs, they're welcome in the comments! A little about how Seen works: during the first visit, Seen caches note heights for the specific window width. Seen also caches the HTML output for the Markdown notes. It caches height by the key SHA256(title + note content), and the Markdown-to-HTML renders by the key SHA256(note content). It uses this cache every other time instead of recalculating, meaning that if most of the content remains unchanged, Seen can render things pretty fast. Caches are saved to IndexedDB. When window width changes, the amount of text that can fit in a line also changes. So, Seen caches heights for specific window widths as well, putting the width in the key. Scrolling triggers an event handler that calculates the current viewport and finds & renders all notes that are visible (or partially visible) with a buffer of a 600px. When a note is deleted or inserted, the entire layout is re-rendered. I plan on optimizing this to only re-render the specific column, which is what happens anyway when a note is updated. Updated notes create new caches (as they should).
More work this month
the category →
The app store for voice native apps that lives in your notch
Work · 28d ago · voiceos.com
The New Calendly▲211Handle all of the work before, during, and after meetings
Work · 17d ago · calendly.com
Launched alongside, February 2025
the whole month →
Screen Studio 3.0▲1,833Beautiful screen recordings with instant shareable links
Growth · 2025 · screen.studio
- IG
I was at FB/Meta from late 2013 to early 2023, mostly working in the compiler/runtime spaces. I got hit in the spring 2023 layoff wave. I immediately started making games in my newfound free time (a lifelong interest, and I even worked in AA(A?) back ca. ~2000), and in October 2023 I stumbled upon the idea of a roguelike pachinko/plinko game inspired by Luck Be A Landlord. Things snowballed quickly, I started talking to publishers, then worked like crazy through all of 2024, almost the hardest I've ever worked in my career, and launched the game in December 2024. It's sold…
Work · 2025
- IB
i wanted to change the habit of reaching for my phone in the morning and doomscrolling away an hour so i built an app to help me. now i have to literally touch grass before accessing my most distracting apps the app is built in swiftui, uses the screen time apis provided by apple and google vision to recognise grass or not i'd love to get your thoughts on the concept.
Life & fun · 2025 · touchgrass.now