iiinova — where your digital self keeps evolving

Reposted by Julien Sulpis

DevFest Lyon @devfestlyon.bsky.social · 27/02/2026

C’est officiel : le DevFest Lyon revient 🚀 📅 4 décembre 2026 au Palais de la Bourse, lieu emblématique du patrimoine lyonnais ✨ 400 participant·e·s, des talks tech, des retours d’expérience et des échanges de qualité 🤝 Dossier de sponsoring bientôt disponible ⏳ Réservez la date 🌟 #DevFestLyon

Affiche DevFest Lyon 2ème édition : Vendredi 4 décembre – Palais de la Bourse”, sur fond de l’intérieur du Palais de la Bourse.

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Julien Sulpis @jsulpis.dev · 26/11/2025

jsulpis.dev is not empty anymore ! For now there is mostly my talks library (in French) and a few side projects. I will probably add a blog in there some day. Of course I am always open to feedbacks

jsulpis.dev

Julien Sulpis

Front-End Engineer

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Julien Sulpis @jsulpis.dev · 25/10/2025

📣 call for feedback! I'm having second thoughts about the naming of the functions in my #webGL library. TL;DR: is it ok to have functions starting with "use" in a vanilla JS library ? explanation in thread 🧵

code snippet with a sample of the functions starting with "use"

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Julien Sulpis @jsulpis.dev · 23/10/2025

Bloom + trails effects on my boids demo ✨ #webGL #shader

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Julien Sulpis @jsulpis.dev · 22/10/2025

OK I've finally made some progress, my trails effect works on a transparent background (dark or light), and the bloom effect too. The trails effect is kind of experimental though, it can produce artifacts in scenes with lots of particles. But I think those two make a great combo ! #WebGL #shaders

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Julien Sulpis @jsulpis.dev · 20/10/2025

I did some tests to fully understand the effect of premultiplied alpha combined with the gamma correction (linear RGB -> sRGB). It seems that the only right way to blend rgba colors is to mix them in linear RGB with premultiplied alpha, and then convert to sRGB. However ⬇️

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Julien Sulpis @jsulpis.dev · 16/10/2025

As expected the trails effect looks cool with particles ! I still struggle with the blending on semi-transparent surfaces, I need to fix that before shipping the effect #WebGL #Shaders #buildInPublic

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Julien Sulpis @jsulpis.dev · 09/10/2025

I've been working on a #WebGL light trail effect lately, and it turns out better than expected ! I just need to refine it a little and make it easy to reuse as a regular post-processing effect, and it should bring particles animations to a new level #buildInPublic

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Julien Sulpis @jsulpis.dev · 26/08/2025

It took me AGES but I finally implemented a decent bloom effect, along with a few tone mapping operators. You can play with it here: usegl.vercel.app/examples/post-processing/builtin-bloom/ #webGL #buildInPublic

screenshot of the bloom example showing a few bright colorful dots with a bloom effect

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Julien Sulpis @jsulpis.dev · 13/08/2025

Debugging #WebGL shaders is hard, but debugging a multi-pass postprocessing effect, well... that's next level 😅 I spent like 2h checking every texture, render target, sampling algorithm... only to find out that I did not returned the right variable in a shader 🤦‍♂️ BUT I think I'm almost there !

git diff showing a change in the returned value of a fragment shader

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Julien Sulpis @jsulpis.dev · 28/07/2025

I have finished setting up Umami on my home server for my websites analytics ✨ It's oddly satisfying to self-host things ! I'm starting small with a simple public API

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Julien Sulpis @jsulpis.dev · 19/06/2025

I should put something at jsulpis.dev 🤔 It's currently used only for my git email and Bluesky handle. Anything you would like to see in there ? Talks library, tech demos, blog...

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Julien Sulpis @jsulpis.dev · 09/06/2025

I made this planet shader after completing @simondev.bsky.social's shader course, and now he has a new bundle including more advanced techniques and maths ? Let's do this ! 🚀 Give me just 10 years to complete all the courses I bought, and I should come up with interesting stuff...

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Reposted by Julien Sulpis

MiXiT @mixitconf.org · 17/04/2025

🎤 Tu te mets combien en responsive CSS ? (Édition 2025) avec @jsulpis.dev et Théo Gianella C’est la base, non ? Mais entre breakpoints, container queries et unités modernes… on s’y perd un peu. Une session en live-coding pour tout remettre à plat. 👉 mixitconf.org/2025/tu-te-m...

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Julien Sulpis @jsulpis.dev · 02/04/2025

I've been playing with the #WebGPU API recently, it's crazy powerful ! A useGPU lib is right around the corner 😂 PS : I will publish the code soon (vanilla WebGPU, OBJ file loader, compute shader and stuff)

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Julien Sulpis @jsulpis.dev · 06/03/2025

Implementing Conway's Game of Life in useGL is relatively easy : I taught Claude the API by feeding it with the boids example, and after a few iterations... you have it, in less than 80 lines of code 😊 Interactive demo : usegl.vercel.app/examples/gpg... #webGL #buildInPublic #gameOfLife

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Julien Sulpis @jsulpis.dev · 04/03/2025

The function to make boids animations, or any other thing using the ping pong FBO technique, is published in usegl ! As always you can play with the interactive example : usegl.vercel.app/examples/gpg... #WebGL #buildInPublic #boids

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Julien Sulpis @jsulpis.dev · 19/02/2025

I am thrilled to give my first talk outside of France at @futurefrontend.bsky.social ! Thanks to m4dz.net for the opportunity 🙏🏻 I will be talking with him about Design Systems. Can’t wait !

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Julien Sulpis @jsulpis.dev · 11/02/2025

It took me a while, but I finally implemented a boids behavior with the ping pong FBO technique. Still need a bit of time to polish the API and make it straightforward to use, and I will publish that in useGL

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Reposted by Julien Sulpis

Xor @xordev.com · 27/01/2025

Subtle things to make your shaders better: 1) Anti-aliasing - Real life is not limited to pixels so unless you're specifically going for a pixelated style, you should be anti-aliasing everything! mini.gmshaders.com/p/antialiasing

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Julien Sulpis @jsulpis.dev · 22/01/2025

Phew, I made an example of a multi-pass bloom effect to showcase the API for creating effect passes and update their uniforms. You can play with it in the interactive example (without types and autocompletion unfortunately) : usegl.vercel.app/examples/pos... #buildInPublic #shaders #WebGL

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Julien Sulpis @jsulpis.dev · 17/01/2025

TIL: there is an equivalent of `requestAnimationFrame` for videos : `requestVideoFrameCallback`, called for each video frame. Could be useful to... automatically re-render a WebGL shader when a video texture is played \o/

sample code for video.requestVideoFrameCallback()

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Reposted by Julien Sulpis

LyonJS @lyonjs.org · 17/01/2025

Il nous a régaler avec des conférences toujours excellentes, gagnant du dernier Code In The Dark, il nous paraissait normal d'inviter @jsulpis.dev pour nous parler cette fois de couleurs.

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Julien Sulpis @jsulpis.dev · 15/01/2025

It looks like it's #PortfolioDay ! I'm a front-end engineer currently focusing on making polished UIs and animations with #WebGL. I'm building a lightweight, reactive WebGL library for working with shaders : usegl.vercel.app (WIP, #buildInPublic) See you 👋

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Julien Sulpis @jsulpis.dev · 09/01/2025

The migration to VitePress is complete ! I hope you will like it as much as I do 😊 usegl.vercel.app/ (yeah it's missing a preview image) #buildInPublic #webGL

usegl.vercel.app

useGL

Lightweight, reactive WebGL library for working with shaders

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Julien Sulpis @jsulpis.dev · 07/01/2025

I really like Astro, but for documentation I prefer the UI and UX of VitePress over Starlight 🤔 Also the lack of top navigation bothers me. I will try to migrate the documentation of useGL 🤞

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Julien Sulpis @jsulpis.dev · 07/01/2025

I'm trying to switch from #Notion to #Obsidian for Personal Knowledge Management (because Notion is slow, owns the data and Obsidian has a better way of linking notes). First impression : it's fast ! Local first + sync via iCloud (or any other cloud) is such a great combo ✨

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Julien Sulpis @jsulpis.dev · 20/12/2024

The documentation is live ! Well, a first draft... only examples for now. I will continue to add features and break a few things before writing the documentation. Any feedback on these first examples would be very appreciated 🙏 usegl.vercel.app #WebGL #buildInPublic

usegl.vercel.app

Home | useGL

Lightweight WebGL library for working with shaders.

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Julien Sulpis @jsulpis.dev · 07/12/2024

I'm playing with particles for an example with useGL. It's crazy that the code fits in my screen ! (useGL helps with that)

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Reposted by Julien Sulpis

marmelab @marmelab.bsky.social · 03/12/2024

🧵 What’s the key to building successful open-source projects? For @react-admin.bsky.social, it’s been all about a strong documentation.🏆 💡Here are our top tips for writing great documentations:👇

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Julien Sulpis @jsulpis.dev · 26/11/2024

I spent way too much time making sure that the playground for the examples looks good on all screen sizes. Yes, even the absolute evil landscape phones ☠️ #buildInPublic

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Julien Sulpis @jsulpis.dev · 21/11/2024

It's starting to look good 😊 I wanted to have many little examples like in the Three.js docs, but where you can directly see and edit the code. I made this with Sandpack and I think it's good enough for now. Maybe one day I will try to add autocompletion with the Monaco editor

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Julien Sulpis @jsulpis.dev · 19/11/2024

OK I think the documentation is done 🤡 What would you need more ?

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Julien Sulpis @jsulpis.dev · 19/11/2024

Learning web APIs is a never-ending journey ! A thread about binary data, JavaScript ArrayBuffer, typed arrays and parallel algorithms on web workers:

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Reposted by Julien Sulpis

LyonJS @lyonjs.org · 18/11/2024

🎉 LyonJS 💯 , la conférence by LyonJS arrive ! 🎉 Pour célébrer notre 100ème événement, LyonJS organise une journée de conférence ! 🎙️ Nous avons déjà 80% de nos sponsors 📅 Si tout se passe bien, la billetterie ouvrira le 6 décembre pour un événement le 21 février. 🎟️ N’hésitez pas à partager ! 🌟

Poster d'annonce de la conférence LyonJS 100 reprenant les info du post.
Une photo du hall de l'UGC Part-Dieu est également intégrée pour illustrer.

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Julien Sulpis @jsulpis.dev · 18/11/2024

I learned the existence of anisotropic texture filtering, that reduces the blurriness of the textures caused by mipmaps. I will make sure to integrate that feature in useGL 😉

demo showing the effect of anisotropic filtering, borrowed from the Three.js website

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Julien Sulpis @jsulpis.dev · 12/11/2024

Still working on the DX of useGL, I guess removing code from the demos is a good sign 🎉

before/after view of a sample code, showing a reduction of the quantity and complexity of code after a change in useGL API

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Julien Sulpis @jsulpis.dev · 11/11/2024

Request for Comments ! 📣 The main "hook" of my upcoming lib, useGL, was originally called "useWebGLCanvas". You give it your canvas, shaders, uniforms etc. Now I think "Web" is unnecessary. But I don't like "useGLCanvas". Maybe... "useGL", like the lib ? 🤯 What y'all think ?

sample code of the "useWebGLCanvas" hook, with a canvas and fragment shader as arguments

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Julien Sulpis @jsulpis.dev · 11/11/2024

I bought a domain name and used it as my handle, but don't bother to search for a website, there is nothing there (yet !) Maybe I should deploy a simple page just so that the url resolves to something ? 🤔

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Julien Sulpis @jsulpis.dev · 05/11/2024

I eventually managed to setup visual testing for useGL 🎉 making consistent screenshots tests on 3 browsers with WebGL and git LFS has been quite a ride 🥲 But now I'm pretty happy with the dev setup : Astro playground with all pages automatically tested ✨ code: github.com/jsulpis/usegl

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Julien Sulpis @jsulpis.dev · 28/10/2024

Sooo I bought 5 courses about creative coding on @awwwards 👀 They add to a 26h long chapter about shaders on #threejsJourney that I have to catch up, @iced_coffee_dev's 2 courses, and 2 Humble bundles with Blender courses.. I think I'm good with learning material until 2026 😅

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Julien Sulpis @jsulpis.dev · 07/06/2024

No surprise here, I would rather write code than tweets 😅 Just found this little app, what are your stats ?! 💬⬇️ (don't take that too seriously of course)

diagram showing that I have a much higher commit count than tweets count

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Julien Sulpis @jsulpis.dev · 05/06/2024

yet another developer on MacOS 🙄 I forgot two things last time: - always use `overflow: auto` instead of `overflow: scroll` unless you specifically want a scrollbar even when there is no scroll - if you have a dark mode, use `color-scheme: dark` to have dark scrollbars

screenshot of a page with many scrollbars

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Julien Sulpis @jsulpis.dev · 28/05/2024

New performance optimization on my reveal.js slide deck : - replace the 3 code snippets I had with screenshots - remove the highlight.js plugin - reduce the weight of the main script by 92% 😅 The plugin loads all languages, I opened an issue to allow loading specific languages

screenshot of the build of my slide deck with the highlight plugin, showing that the largest script weights 332kB (minzipped)

screenshot of the build of my slide deck without the highlight plugin, showing that the largest script weights 28kB (minzipped)

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Julien Sulpis @jsulpis.dev · 28/05/2024

I investigated performance issues with the reveal.js slide deck of my latest talk, and I turns out that each slide change created like 1500 DOM nodes 😳 I ended up with ~100k DOM nodes at the end... I guess every layout/style recalculation was taking forever. solution:

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Julien Sulpis @jsulpis.dev · 21/05/2024

After a little break, I'm back in the #WebGL game ! Working on color science for my next talk 🎨 Here is a little HSV cone (links in comments):

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