MegaMOO

What MegaMOO is

MegaMOO is a text-based virtual world engine — the LambdaMOO model rebuilt from scratch in Python 3. It hosts a shared, programmable world that players connect to over telnet or websocket, where they move between rooms, handle objects, and talk to each other. Builders and programmers extend that world while it is running, by writing code directly into the live database.

It combines the object-oriented model LambdaMOO proved in 1990 with modern Python: asyncio networking, SQLite persistence, and the full standard library available inside the world's own code.

A browser client is included. Start a world with --web and players can play it in a browser with no client to install — a terminal with colour and clickable exits, a map that draws itself as they explore, and their own triggers and aliases in Lua or JavaScript. Telnet players and browser players share the same world. See The Web Client.

A small footprint

MegaMOO is one Python process and one database file. Installing it is pip install megamoo, and that is the whole of it: the engine has zero third-party dependencies, so there is nothing further to satisfy — no web server to configure, no database server to administer, no build step, nothing to compile. (The one vendored library anywhere in the project is the Lua interpreter the browser client's optional scripting host uses; it ships as a static file.)

That matters more than it sounds. It means a world costs nothing to keep running and can live on a laptop or the cheapest VPS you can rent. The running world is a single file you can copy; the source you write — verbs/ and game/ — is an ordinary directory that belongs in git. And you can run five worlds at once on one machine without them interfering with each other.

Built to be worked on with an AI assistant

MegaMOO exposes its live world through a local API, so an AI assistant can work inside the running game rather than guessing at it from source files. Connected that way, an assistant can read what an object really holds, write a new command, run it as a test character, read exactly what the game printed back, and check the log when something breaks — then fix it, with the world still running and players still connected.

The engine's design happens to suit this unusually well. Every command is a short, self-contained Python file with a fixed set of variables available and no imports to resolve, so a single command is a small, bounded problem — the kind an assistant handles reliably. World-building stops being a slow edit–restart–reconnect loop and becomes a conversation.

What you get out of the box

Where to go next