Skip to main content

FluffOS

FluffOS is a high-performance game engine (an LPMUD driver), commonly used for building MUDs — see LPMud. Started as a collection of patches to the last release of MudOS, FluffOS has gone through major rewrites and bugfixes to support new features while maintaining backward compatibility with existing mudlibs.

The codebase has three parts:

  • LPC interpreter — parses and executes LPC programs.
  • Network server — manages client connections and exposes them to LPC. Supports TELNET, TLS and WebSocket.
  • Glue interface
    • Efuns — built-in C/C++ functions callable from LPC programs.
    • Applies — callback functions the driver invokes on LPC objects for game events.
Current release

The current release is branch master — CMake build system, supported on Ubuntu, macOS, Windows (MSYS2/MinGW64), and WebAssembly. See all releases on GitHub.

Explore the documentation​

🚀 Getting Started

Build the driver from source on Linux, macOS, Windows — or for the browser with WebAssembly.

Build Guide

📖 LPC Language

The LPC language as implemented by FluffOS: types, constructs, the preprocessor, and compiler diagnostics.

Language Reference

⚙️ Efuns

The complete reference of built-in functions the driver exposes to LPC code, grouped by topic.

Efun Reference

🔔 Applies

Callbacks the driver invokes on your objects: master security hooks, object lifecycle, and player connections.

Apply Reference

💡 Concepts

How LPC, objects, and the driver fit together — simul_efuns, hot reload, networking, and more.

Concept Guides

🔧 Driver Internals

Runtime configuration, the VM stack machine, memory allocation, and how to add your own efuns.

Driver Docs

Features​

  • Builds on Ubuntu, macOS, and Windows natively with CMake — plus a WebAssembly target that runs a full mudlib in the browser.
  • UTF-8 native, with transparent input/output encoding support. (Emojis!)
  • WebSocket support!
  • TLS support!
  • SHA512 crypt by default.

Features previously released​

  • Mostly backward-compatible with MudOS. (Upgrading should be easy!)
  • Lots of bug fixes, including a full CHECK_MEMORY-enabled testsuite pass.
  • Compiles on modern Linux distros, 32-bit & 64-bit, CYGWIN support.
  • 64-bit LPC runtime: LPC int is always a 64-bit int, LPC float is a C double.
  • MXP, GMCP, ZLIB.
  • IPv6 support (optional).
  • ICONV support: code in UTF-8, dynamic translation on output (optional).
  • POSIX timer for better time precision (optional).
  • Stricter type checking (optional).
  • libevent integration, epoll backend.

License & Copyright​

Copyright 2019-2023 Yucong Sun

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

Historical​

For the pre-2019 license and copyright, see Copyright; for older release notes, see ChangeLog.fluffos-3.x.