Open-source alternatives to Cuberite

Warzone 2100 is an open-source real-time strategy game engine focused on tactical combat and base building. It operates as a real-time strategy game engine utilizing a data-driven asset pipeline and providing cross-platform support. The project features a modular unit design system that uses a technology tree to construct combat entities by combining chassis, propulsion, and weapon components. It includes a lockstep multiplayer network engine to synchronize game state across distributed clients for competitive matches, as well as a JavaScript game scripting framework for implementing custom l

This project is an open-source 3D game engine designed for building high-fidelity games, simulations, and cinematic environments. It functions as a robotics simulation platform with native integration for ROS 2 to model robot controllers and sensors. The engine features a multi-threaded Forward+ physically based renderer that supports hardware-accelerated ray tracing and global illumination. The system is built on a modular extension architecture using Gems to add or replace features without modifying core binaries. It includes a native SDK for AWS cloud integration, enabling IAM authenticati

Spring is a cross-platform game engine and framework designed specifically for the development and execution of multiplayer real-time strategy games. It provides a high-performance simulation environment for managing large-scale battles and unit movements across different operating systems using a shared codebase. The engine functions as a multiplayer game server and networking layer, coordinating real-time game state and match synchronization between remote players. It includes a dedicated lobby client system for multiplayer match coordination as well as the capability to execute single-play

Pumpkin is a high-performance Minecraft game server implementation designed to host shared virtual worlds. It is specifically built to support multiple client editions, allowing different game versions to interact within a single world. The project distinguishes itself through a flexible plugin architecture that supports extensions written in Go and Python. These extensions are loaded as portable binary modules, enabling developers to implement custom game logic and modify server behavior without altering the core codebase. The server covers a broad range of operational capabilities, includi

Nakama is a distributed server framework designed for real-time multiplayer games and social applications. It provides an authoritative runtime environment for executing game logic, ensuring consistent state and cheat-resistant gameplay across diverse client platforms. The system acts as a centralized backend, managing persistent player identities, social graphs, and real-time communication channels to support complex multiplayer interactions. The platform distinguishes itself through an integrated suite of LiveOps tools that allow developers to manage game economies, schedule time-bound even

Colyseus is a real-time multiplayer game framework for Node.js that provides an authoritative server model, delta-compressed state synchronization, and room-based session orchestration. It is designed to handle the core infrastructure of multiplayer games, including matchmaking, state management, and scalable process distribution across multiple servers. The framework distinguishes itself through its schema-based state definition, which enables automatic serialization and change tracking, combined with a binary WebSocket protocol for low-latency updates. Its matchmaking pipeline routes player

This project is a World of Warcraft server emulator that simulates a multiplayer online game world, managing player data and game logic. It functions as a modular game server framework and an NPC AI and scripting engine, providing the necessary infrastructure to host a persistent virtual environment. The system is distinguished by a modular framework that allows for the extension of core engine behavior through isolated modules and function hooks without modifying the source code. It includes a structured SQL data layer for managing authentication, character states, and world environment sett

NoahGameFrame is a distributed game server framework designed for real-time multiplayer games. It utilizes an actor model backend to manage game state and logic through an asynchronous, event-driven system that distributes workloads across multiple CPUs. The framework features a scriptable server environment that integrates external scripting languages, allowing for updates to game behavior and mechanics without restarting the server. It also employs a plugin-based architecture with an interface-oriented design to enable the addition of custom application logic and modular engine extensions.

This project is a browser-based, real-time multiplayer action game where players control a character on a 2D canvas to absorb objects and grow in size. It utilizes a Node.js game server and WebSockets to synchronize game state, player movement, and chat across all connected participants. The application is delivered as a dockerized game application, ensuring consistent hosting and deployment across different cloud environments through containerized server environments. The system implements an authoritative server model that processes all game logic and physics to prevent cheating and mainta

OpenRCT2 is an open-source reimplementation of a classic amusement park management simulation engine. It functions as a cross-platform engine that modernizes the original game, enabling it to run on contemporary operating systems while maintaining full compatibility with legacy assets and data files. The project distinguishes itself by providing a comprehensive multiplayer simulation server that supports cooperative, real-time park management and construction across multiple connected clients. It utilizes a deterministic lockstep networking model and a centralized action-based validation syst

Lila is an open-source chess server and multiplayer platform designed for playing, analyzing, and streaming games. It functions as a comprehensive environment for hosting competitive play and managing player profiles. The platform integrates a distributed chess engine interface to evaluate complex positions and a collaborative analysis board that allows multiple users to study and coordinate insights in real time. It also includes an online tournament platform for organizing competitive events, simultaneous exhibitions, and structured player leagues. The system maintains a searchable game da

This project is a game server management panel and multi-user administration tool. It provides a centralized web interface and orchestrator for deploying, configuring, and monitoring game servers running inside isolated Docker containers. The system manages the full lifecycle of server instances, from mapping network allocations and IP addresses to enforcing resource limits through containerization. It includes a hosting dashboard for handling server backups via local or cloud storage and a control plane for remote-agent communication with server nodes. Administrative capabilities cover role

CatServer is a hybrid Minecraft server implementation designed to simultaneously execute Forge mods and Bukkit or Spigot plugins within a single environment. It functions as a runtime bridge that enables the integration of heterogeneous modding and plugin ecosystems, allowing content from both sources to operate together. The project provides a compatibility layer that translates plugin dependencies and synchronizes data between external extensions and internal game logic. By utilizing a unified classloader hierarchy and runtime bytecode instrumentation, it allows standard server extensions t

FiveM is a multiplayer modification framework and game engine modding tool. It serves as a platform for creating and hosting community-driven modifications for open-world game engines, functioning specifically as a framework for Grand Theft Auto V to enable custom servers and multiplayer game modes. The project provides a dedicated game server host for managing network traffic and synchronized game states in modified environments. Its capabilities extend to modding Red Dead Redemption 2, allowing for the extension of game mechanics and the addition of custom content. The framework supports c

Unciv is an open-source, cross-platform turn-based strategy game and a community-driven remake of a commercial strategy title. It simulates empire building, city management, and technological research for players on Android and desktop platforms. The project is designed as a moddable game engine, allowing users to override gameplay rules, modify units and buildings via external definition files, and replace audiovisual assets. It supports the distribution of custom maps and the ability to import mod archives from remote web addresses. The application includes a dedicated server for multiplay

Tenet is a Java-based Minecraft server runtime designed to host multiplayer sessions that incorporate both complex custom content and server-side modifications. It functions as a modding platform that integrates distinct server ecosystems into a single, unified environment. The project distinguishes itself by enabling the simultaneous execution of Forge mods alongside Bukkit or Spigot plugins within one server instance. By bridging these traditionally separate frameworks, it allows administrators to combine diverse gameplay features and management tools that would otherwise be incompatible.

Craft is a multiplayer voxel sandbox written in C. It utilizes an OpenGL voxel engine to render a block-based world and implements an infinite terrain generator that uses noise functions to create deterministic, procedural landscapes. The project features a networked environment where players can build and modify a shared world using socket-based state synchronization. To maintain consistency across sessions, it employs a voxel world database to store and retrieve modified block coordinates. The system covers a range of capabilities including 3D collision detection for character movement, to

Veloren is an open-source multiplayer RPG featuring a voxel-based action adventure in a procedurally generated fantasy world. It is built upon a voxel game engine that supports 3D rendering via Vulkan and Metal, utilizing a procedural world generator to create geography and ecosystems based on erosion algorithms and temperature maps. The project is distinguished by a sandboxed plugin system using WebAssembly, which allows for the addition of new game logic and equipment without recompiling the core engine. It also features a dedicated game server architecture designed to synchronize state, ma

BrowserQuest is a WebSocket multiplayer game engine and real-time state synchronization tool. It functions as a web-based game server designed to manage concurrent connections and broadcast updates to maintain a consistent shared world state between a central server and distributed web clients. The project enables real-time multiplayer gaming and browser-based game development by implementing low-latency data exchange. It focuses on game state synchronization to ensure that multiple players interacting within the same environment see the same actions and world states simultaneously. The syst

Unreal.js is a JavaScript runtime and scripting layer for Unreal Engine that embeds the V8 engine to implement game logic and manage application state. It provides a bridge for writing high-level application behavior and actor control without modifying the core engine source code, as well as a framework for extending the Unreal Engine editor with custom interface elements. The project distinguishes itself through a V8-based integration that supports real-time code reloading and live iteration, allowing scripts to be updated without restarting the application. It includes a bidirectional commu

This is the original C source code for the Quake game engine, a landmark first-person shooter engine from the 1990s. It is a retro game engine that renders 3D environments and processes player input in real time using CPU-based software rendering rather than GPU acceleration. The engine supports networked multiplayer gameplay over LAN or internet connections and is designed to be moddable, allowing users to create and run custom game modifications and levels. The engine's architecture includes a Binary Space Partition tree for efficient world geometry organization and visibility determination

OpenMW is a modern, open-source game engine designed to execute the game Morrowind and its expansions. It serves as a cross-platform game runtime and 3D world renderer, providing a data-driven environment to run game logic and physics with improved stability. The project functions as a game modding framework, utilizing a modular plugin system and an interpreted scripting layer to load external modifications. This architecture allows for the integration of community content, custom textures, and external scripts without altering the base executable code. The engine covers a broad range of cap

Defold is a cross-platform game engine and integrated development environment used to create 2D and 3D games for desktop, mobile, and web targets. It combines a game development IDE for asset and scene management with a multi-platform build system and a scripting environment based on Lua. The engine includes a specialized headless runtime for hosting game servers and performing automated testing without a graphical interface. It supports native engine extensions, allowing custom low-level code to be integrated into the core to expand functionality beyond the standard scripting interface. The

This repository is a comprehensive collection of functional 2D and 3D demo projects and implementation samples for the Godot Game Engine. It serves as an interactive tutorial and reference library, providing a working codebase to demonstrate how to apply engine features in real-world scenarios. The collection focuses on practical implementation guides, covering a wide array of technical capabilities from basic engine fundamentals to advanced rendering and scripting techniques. It allows users to study the application of node-based composition, asset pipelines, and game logic through direct ex

jynew is a 3D RPG game engine and development framework designed for building three-dimensional role playing games. It provides a comprehensive suite of tools for scene editing, game logic scripting, and the creation of 3D environments. The project features a specialized 3D asset management pipeline for importing and aligning models and animations, including specific tools for weapon attachment and rendering. It includes a dedicated combat system editor for defining battle encounters, skill effects, and combat grids with real-time synchronization. Additionally, it provides a game modding fram

Minetest Game is an open-source voxel sandbox engine that provides a foundational environment for building, exploring, and modifying procedurally generated worlds. It functions as a creative platform where users can construct complex structures and interact with a three-dimensional, block-based landscape without predefined goals or hostile entities. The project distinguishes itself through a modular architecture that separates game mechanics from the core engine. By utilizing a sandboxed scripting environment and event-driven hooks, it allows for the dynamic modification of game behavior, ena

TIC-80 is a fantasy console platform and multi-language game engine that provides a virtual retro game development environment. It operates via a bytecode virtual machine that executes game logic within fixed memory and resolution constraints. The project distinguishes itself by offering integrated asset editors for pixel art, tile maps, and a pattern-based chiptune audio workstation all within a single environment. It supports multi-language scripting, allowing developers to write logic in Lua, JavaScript, or Ruby, and provides a standalone game exporter to package projects into native execu