Build 3D prototypes in your browser — alone or together.
Peer-to-peer, no account, no server holding your scene. Free and open source.
A collaborative 3D editor that runs entirely in the browser. Drop in primitives or your own models, wire up behaviour in a node graph, turn on physics, and walk through the result in VR — then send someone your peer ID and they are editing the same scene with you, in real time.
There is no backend. Sessions run over a peerjs mesh: a signalling server introduces peers, then everything — objects, node graphs, voice, cursors, files — travels directly between browsers. Nothing about your scene touches our servers, and you can point the app at your own signalling server or self-host the whole thing.
| Repo | What it is |
|---|---|
| core | The app. SvelteKit + Svelte 5, three.js / Threlte, WebXR, Rapier physics, the node editor and the module SDK. MIT. |
| docs | User and SDK documentation — published to docs.theprototype.app. |
| modules | Optional and community modules, installable from a .zip or a URL. One folder per module. |
| packs | Content packs — CC0 models and audio, served to the app over jsDelivr. |
Everything you need to build, collaborate and self-host is in core, under MIT, with no
feature gates. An optional hosted tier (accounts, room listing, roles) plugs into a small
set of documented seams — a capability gate, an auth hook and a plugin URL. With no plugin
loaded, the open-source build behaves byte-identically. The contract lives in
OPEN-CORE.md.
- Try it — theprototype.app, nothing to install, no sign-up
- Read the docs — docs.theprototype.app
- File something — issues on core
- Write a module —
MODULES.md - Watch it in action — video playlist
Sponsoring helps pay for the signalling and relay servers that keep public sessions connecting. Starring the repo and telling someone about it helps just as much.
