April 26, 2026
Ctrl+Drama+Del
Lessons from building multiplayer browsers
Multiplayer browsers: big idea, small vibes, karaoke energy
TLDR: A founder recounts why a “multiplayer browser” with shared canvases didn’t catch on, despite big backing. Comments split between “cool demo, felt small,” karaoke-fueled nostalgia, and hopes that AI could revive the idea—highlighting how hard it is to turn bold interface dreams into daily tools.
A former engineer from Sail/Muddy just spilled lessons from trying to build a “multiplayer browser”—think shared tabs, live cursors, and an infinite whiteboard baked into your window. The backstory is pure startup catnip: a tiny team, big-name investors, and a fork of Chrome’s code, all chasing a new way to work online. But the comments quickly stole the show. The author’s own note sets the tone—this is for people chasing ambitious interfaces, now with AI in the mix.
One reader poked the bear with a sharp question: did Sail/Muddy feel “small in the mind of the user”? Translation: powerful tech, but not a life-swallowing platform like Figma or Notion—more like a neat feature looking for a home. Meanwhile, another commenter turned the vibe up to 11, reminiscing about building a similar multiplayer canvas that accidentally birthed a YouTube karaoke room—real-time video tech made it a little laggy, but close enough for singalongs. And then came the deep cuts: someone dropped a link to Eagle Mode, a cult “zoom into everything” interface, fueling the eternal debate between wild new canvases vs. tools that just get out of the way. The crowd’s split: some see a noble swing at the future, others say it never escaped the “cool demo” zone—and wonder if AI finally gives this idea its encore.
Key Points
- •In 2022, the author joined as a founding engineer to build Sail and later Muddy, aiming to create a multiplayer/team browser.
- •The team forked Chromium, enabling access to tabs and the History API and allowing UI to be built with web technologies.
- •The company raised a $5.5 million seed round from General Catalyst, Naval Ravikant, Lachy Groom, Y Combinator, and others.
- •Sail started as an infinite canvas app integrating websites, text cards, and collaborative cursors; the team iterated and drew inspiration from tools like Muse and Kinopio.
- •Despite extensive effort, the company did not achieve product-market fit; building and maintaining a browser proved unusually difficult.