Open source. Open possibilities.

A lightweight .NET library for building text-based adventure games, with rooms, NPCs, items, commands, conversations, maps, rendering frames and save support.

A Haskell DSL for writing parser-based text adventures, inspired by Inform 7 and aimed at procedural generation of large interactive fiction worlds.

A Rust port of the BepuPhysics v2 physics engine, translated line by line from the original C# library. It offers SIMD-optimized collision detection and constraint solving, lock-free multithreaded scheduling, spatial queries, and an optional Bevy plugin. Requires Rust nightly and supports macOS NEON or x86_64 SSE/AVX2.

Phaser is a fast, free, and open-source HTML5 2D game framework for desktop and mobile web browsers, supporting both Canvas and WebGL rendering.

raylib is a simple, easy-to-use C library for videogame programming, ideal for prototyping, education, and graphical applications.

libGDX is a cross-platform Java game development framework based on OpenGL (ES) for Windows, Linux, macOS, Android, web browsers and iOS. It supports 2D and 3D games, uses Gradle for setup, is Apache 2.0 licensed, and has a large third-party ecosystem.

A C++20 framework for shipping raylib games to 17 platforms from one codebase, with CI that builds and verifies rendering. Users edit only src/, resources/, and a TOML config.

Zero-dependency LÖVE2D framework with scenes, input, saves, audio, UI, ECS, physics, and in-game scene editor. Includes reference game Gem Haul. Targets LÖVE 11.5, no third-party libraries.

Valve's GameNetworkingSockets is a cross-platform transport layer for games offering reliable/unreliable UDP messages, fragmentation/reassembly, P2P networking, NAT traversal via ICE, and AES-256-GCM encryption.

Remembering Home is a 2D game built with LÖVE (Love2D) framework, featuring an Entity Component System, AI behavior trees, and various libraries for animation, collision, and GUI. It includes build scripts and tools for development.

Pebble is a low-level, ECS-style graphics framework for Rust built on wgpu, winit, and hecs, providing a flexible skeleton for building custom rendering pipelines.

H5P Game Map is an H5P content type that lets students choose their exercises from a game map. The repository documents its npm build, lint and h5p pack workflow; it is contract work offered free of charge with no guaranteed support.

PunyInform is an Inform 6 library for creating text adventure games for the Z-machine, optimized for small memory and 8-bit computers, with parser, verbs, and authoring framework.

An interactive storytelling framework that uses LLMs to generate dynamic narratives based on predefined, graph-based story paths.

JavaScript library for generative text using context-free grammars and Markov chains, interactive stories with decision trees, and image grammars (igramas).

pygame is a free, open-source, cross-platform Python library for building multimedia applications and games, built on SDL. It offers 2D graphics, sound, input handling, and game development tools like sprites and collision detection.

Wuxia, Start! is an open-source Unity-based wuxia RPG framework inspired by the classic DOS game, featuring script-driven flows, visual editing, and multiple sample MODs. It supports full modding, turn-based combat, and multi-platform builds under MIT license.

A lightweight C++ game framework using SDL and miniaudio, designed for rapid prototyping with scene management, asset loading, and tick systems.

PGX is an open-source, modular C++ gameplay framework for Unreal Engine 5, designed to unify configuration, extension, and diagnostics.

An agentic AI role-playing game framework where narration, NPCs, lore, and character creation run as composable plugin agents, with stage and text modes, portable world packs, and support for OpenAI, Anthropic, DeepSeek, and Qwen.