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Fallout 3 / New Vegas multiplayer mod (vaultmp, 0.1a) - item / health sync - YouTube

Vault-Tec Multiplayer Mod ("VaultMP") is a multiplayer mod for the PC versions of Bethesda's award-winning role-playing games Fallout 3 and Fallout: New Vegas. It's currently in development, but is going to support the


  • Dedicated server, MasterServer and client including a server browser
  • Syncing of movement, actions / animations and AI
  • In-game GUI overlay for chatting
  • Supporting DLCs as well as Fallout user mods
  • Server-side scripting to define gameplay rules

What vaultmp is - and what it isn't

is actually not the best fitting keyword in my opinion. VaultMP is supposed to be much more like a framework. It aims for extensibility and scalability. The goal is to provide the tools necessary to create engaging online environments in the Fallout games. It does not impose any limits on what you can do with it (i.e. maximum player count), neither does it has any bias towards any kind of multiplayer game.
VaultMP is not a co-op mod, a MMO, or anything else of the like. The community is free (and encouraged) to take VaultMP and develop server-side game modes, composing the actual rules of gameplay. Therefore VaultMP exposes a rich scripting interface, with a C API at its core, as well as native support for C++11 and PAWN scripts.

is not:

  • Co-op, MMO, deathmatch, etc.


  • A framework to create any kind of multiplayer game


is one of the most important features of Vault-Tec Multiplayer Mod. It grants access to in-game Objects and allows to manipulate them. With the help of scripts, it is possible to customize the game experience and even create whole new gamemodes. Scripts are executed server-side by the dedicated server of vaultmp. Users who code scripts are known asscripters. They mainly use the scripting functions and scripting callbacks (see VaultMP interface) provided by the mod to write a script. A script can be written inC++ or in the PAWN language. See the section Installing a script in the dedicated server setup guide on how to load such a script.
C++ scripting

Scripts can be written in C++. It allows for maximum flexibility and an extremely large set of possibilities. An example script comes with the vaultmp package including project files for Code::Blocks IDE. C++ scripts need to be compiled as dynamic-link library (shared object for Unix) files. The entry point of a C++ script is exec.


Vault-Tec Multiplayer Mod is a rather huge project and I would be grateful if it had some more
developers. Work on vaultmp can be exciting and very diverse. It deals with the game engine (low-level), networking code, scripting and various design patterns. Most parts aren't easy to understand so you are required to have some well established C++ knowledge. However, I'm happy to answer any question regarding the source code!

If you are interested, write me a mail ( The source code is available

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