A decentralised social network built on Secure Scuttlebutt.
Secure Scuttlebutt is a gossip protocol: every device holds a full, append-only log of everything its owner has said, and peers replicate each other's logs whenever they happen to be near each other — over the internet, over local wifi, on a USB stick if that's what's available. There's no server to shut down and no company standing between you and your own words.
Planetary was the client we built on top of it: a social app that looked and felt like the mainstream apps everyone already knew, while quietly running on an entirely different, peer-to-peer foundation underneath. The hard design problem wasn't the protocol — it was hiding an enormous amount of genuinely strange infrastructure behind something that felt, deliberately, unremarkable.