BepInEx is a free, open-source framework for installing plugins and mods in Unity Mono, Unity IL2CPP, and .NET Framework games, including XNA, FNA, and MonoGame titles. It provides configuration and logging, runtime method patching, and in-memory assembly patching. Runtime patching uses Harmony, including HarmonyX and MonoMod; in-memory patching uses Mono.Cecil with UnityDoorstop. The installation guide covers Windows, Linux, and macOS, although supported versions and architectures vary by build and game. Setup is manual: download the appropriate build and put its contents in the game's root folder. Official binaries are available as stable and bleeding edge builds; the documentation recommends stable builds in most cases and notes that bleeding edge builds tend to be buggier. Compatibility is limited: only Unity Mono has stable releases, and BepInEx 6 documentation is marked as work in progress. BepInEx 5 is in long-term support, and its plugins do not yet work with the BepInEx 6.0.0 pre-release. User and developer guides cover installation, configuration, troubleshooting, and plugin development.
Who it is for
It suits people modding supported games and developers writing plugins for them. The project provides separate user and developer guides for setup and plugin work.
What is good
- Supports Unity and .NET Framework game types
- Includes configuration, logging, and patching tools
- Runs on Windows, Linux, and macOS
- Open source under the LGPL-2.1 license
What to know first
- Installation requires manual file placement
- Only Unity Mono has stable releases
- BepInEx 6 documentation is work in progress
- BepInEx 5 plugins do not work with the 6.0.0 pre-release
Verdict
BepInEx provides mod loading and plugin development tools for several game frameworks. Check the game's compatibility and choose a build carefully, especially where stable support matters.
BepInEx plans and pricing
All plansCompared on game mod loaders
- Free plan
- Yes
- Supported platforms
- Windows, macOS, Linux
- Mod loading method
- injection
- Plugin support
- Yes
- Load-order control
- Yes
- Dependency handling
- Yes
