What Is open.mp?

Updated

open.mp (Open Multiplayer) is a multiplayer mod for Grand Theft Auto: San Andreas that is fully backwards compatible with San Andreas Multiplayer (SA:MP). If you already run SA:MP scripts or play on SA:MP clients, open.mp is designed to work with them out of the box — you can load an existing AMX script onto an open.mp server and join from the SA:MP client. It is aimed at server owners and scripters who want to keep their existing SA:MP setup while gaining a more actively developed, open-source platform.

Backwards compatibility with SA:MP

The core promise is compatibility, not replacement-with-migration-pain:

  • Existing scripts run as-is. An old AMX file can be loaded on an open.mp server "straight out of the box."
  • Existing clients connect. Players using the SA:MP client can join an open.mp server.
  • Enhancement is optional. You only move to the newer scripting features when you choose to improve your code.

This matters if you maintain a live SA:MP community: you can switch the server side without forcing players to install something new.

What open.mp adds on top

A new scripting system (still Pawn)

open.mp keeps Pawn as the scripting language but ships a new compiler engineered to make code more robust, plus additional functions for manipulating the server and client. So the learning curve for existing SA:MP scripters stays low, while the tooling and API surface improve.

An extensible C++ API

Through the SDK, you get access to all the server features available in Pawn, plus the wider universe of C++ libraries and frameworks. This is the path to take if you want to extend the server beyond what scripting alone allows.

Open-source, community-driven development

The server is fully open source and contributions of any size are welcome. You can help write the next version, or report problems you find — the project acknowledges that bugs happen and treats feedback as valuable.

Who it's for

If you are… open.mp is relevant because…
A SA:MP server owner You can run existing scripts and keep SA:MP clients connecting
A Pawn scripter Same language, new compiler, more functions
A C++ developer The SDK exposes full server features plus C++ libraries
Someone who wants to contribute The server is open source with an open contribution process on GitHub

How to get started

  1. Check compatibility first. Confirm your existing AMX script and your players' client setup match what open.mp supports — the project states backwards compatibility with existing scripts and clients.
  2. Load your script on an open.mp server. The documented expectation is that an old AMX loads out of the box.
  3. Connect with the SA:MP client to verify players can join as before.
  4. Then enhance. When you want to improve your code, move on to the docs covering the new scripting system.
  5. Go further with C++ if you need server features beyond Pawn, via the SDK repository.
  6. Contribute or report issues through the GitHub organization.

The official site (open.mp) links to Getting Started documentation, the SDK repository, and the GitHub organization for contributions.