Third Room Tech Preview: open decentralised worlds built on Matrix

In plain words

Third Room is an open-source platform for building decentralized virtual worlds on the Matrix protocol. It enables users to create and explore interconnected 3D environments without cryptocurrency, NFTs, or centralized servers. Built on Manifold, a web-based game engine delivering 60fps performance, Third Room uses standard web technologies including Three.js, bitECS, and Rapier physics. Designed for developers and users seeking open, interoperable virtual spaces, it runs on Matrix homeservers and is available as a public tech preview.

written from the facts on this page · September 2026

From the sources

Open, decentralised, immersive worlds built on Matrix

In the maker’s words, at launch

Hi all, We just launched the first public tech preview of Third Room: an open source, standards-based, decentralised vision of interoperable virtual worlds for the open Web, built entirely on Matrix - without cryptocurrencies, NFTs or walled gardens. It's built on an new opensource game engine for the web called…

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