# leanclr **Repository Path**: lightsever/leanclr ## Basic Information - **Project Name**: leanclr - **Description**: LeanCLR 是一个面向生产发布的 CLR实现，核心目标是提供高 ECMA-335 兼容度、低集成复杂度和强跨平台能力，真正实现 “Write C#, Run Anywhere”。 这是从官方github仓库的镜像 - **Primary Language**: Unknown - **License**: MIT - **Default Branch**: unity - **Homepage**: None - **GVP Project**: No ## Statistics - **Stars**: 0 - **Forks**: 0 - **Created**: 2026-06-23 - **Last Updated**: 2026-06-23 ## Categories & Tags **Categories**: Uncategorized **Tags**: None ## README # LeanCLR Language: [中文](./README.md) | [English](./README_EN.md) [![GitHub](https://img.shields.io/badge/GitHub-Repository-181717?logo=github)](https://github.com/focus-creative-games/leanclr) [![Gitee](https://img.shields.io/badge/Gitee-Repository-C71D23?logo=gitee)](https://gitee.com/focus-creative-games/leanclr) [![license](https://img.shields.io/badge/license-MIT-blue.svg)](https://github.com/focus-creative-games/leanclr/blob/main/LICENSE) [![DeepWiki](https://deepwiki.com/badge.svg)](https://deepwiki.com/focus-creative-games/leanclr) [![Discord](https://img.shields.io/badge/Discord-Join-7289DA?logo=discord&logoColor=white)](https://discord.gg/esAYcM6RDQ) LeanCLR is a production-oriented CLR implementation. Its core goal is to provide high ECMA-335 compatibility, low integration complexity, and strong cross-platform capability, so developers can truly achieve **“Write C#, Run Anywhere.”** ## Why LeanCLR For teams that need to embed C# logic into a host application and ship to multiple platforms, CoreCLR, Mono, and IL2CPP typically have the following limitations: - **CoreCLR** and **Mono**: Feature-complete runtimes, but with relatively high binary size, dependency footprint, and host integration complexity. Their trimming and porting costs are often too high for lightweight embedded deployment scenarios. - **IL2CPP**: Closed-source, tightly coupled to Unity tooling and ecosystem, AOT-only, and with limited ECMA-335 coverage. LeanCLR is designed to fill this gap: maintain high ECMA-335 compatibility while delivering an embeddable, compact, and efficient cross-platform CLR. ## Key Features - **Strong cross-platform support** — AOT + Interpreter hybrid execution model with no JIT, implemented in standard C++11 and free of platform-specific dependencies. - **Easy integration** — Integration complexity is close to Lua; easy to embed into apps, games, embedded devices, IVI/automotive platforms, and more. - **High ECMA-335 compatibility** — Near-complete support for ECMA-335 and major CoreCLR extensions, including generics, exceptions, reflection, and delegates. - **Compact and efficient** — Small binary size, low memory usage, and high runtime efficiency; single-thread core build is under **600 KB** on x64/WebAssembly and can be reduced to around **300 KB** after trimming. ## Documentation Full documentation site: **https://doc.leanclr.com** - [Getting Started](https://doc.leanclr.com/docs/getting-started/overview) - [Build & Integration](https://doc.leanclr.com/docs/integration/overview) - [AOT](https://doc.leanclr.com/docs/aot/overview) - [Interop](https://doc.leanclr.com/docs/interop/overview) - [Testing](https://doc.leanclr.com/docs/development/testing) - [Contributing](https://doc.leanclr.com/docs/development/contributing) ## Supported Platforms (Standard) Standard edition currently supports: | Platform | Notes | |------|------| | **Windows** | Desktop targets such as Win64 | | **Linux** | Desktop and embedded Linux | | **macOS** | Desktop targets | | **Android** | Mobile | | **iOS** | Mobile | | **HarmonyOS** | Harmony ecosystem | | **WebAssembly** | Web browsers and mini-game platforms | ## Ecosystem & Integrations LeanCLR already supports Unity and is actively integrating Godot and CoreCLR BCL, with more engines and platforms to follow. | Platform / Integration | Status | Notes | |------|------|------| | **Unity / Unity China, WebGL and Mini-Game platforms** | ✅ Complete | [leanclr-unity](https://github.com/focus-creative-games/leanclr-unity): replace IL2CPP with LeanCLR when shipping games (not limited to WebGL/mini-game platforms) | | **Godot (all platforms)** | 🚧 In development | [leanclr-godot](https://github.com/focus-creative-games/leanclr-godot) is being integrated with the Godot engine | | **CoreCLR .NET 10 BCL** | 🚧 In development | The Standard `coreclr` branch is adding .NET 10 BCL support | | **Unreal Engine (all platforms)** | 📋 Planned | ETA TBD | ## Project Status ### Current Progress | Module | Status | Notes | |------|------|------| | **Metadata Parsing** | ✅ Complete | Full PE/COFF and CLI metadata table support | | **Type System** | ✅ Complete | Classes, interfaces, generics, arrays, value types, etc. | | **IR Interpreter** | ✅ Complete | Optimized execution for hot functions | | **Exception Handling** | ✅ Complete | try/catch/finally, nested exceptions, etc. | | **Reflection** | ✅ Complete | Type, MethodInfo, FieldInfo, and other core APIs | | **Delegates** | ✅ Complete | Unicast/multicast, generic delegates | | **Internal Calls** | ✅ Complete | Currently focused on Core edition icalls | | **P/Invoke** | ✅ Complete | Supports manual registration and LeanAOT-generated P/Invoke wrappers | | **Garbage Collection** | ✅ Complete | Precise Mark-Sweep full GC | | **AOT Compiler** | ✅ Complete | IL → C++ transpilation supported | | **Multi-threading** | 📋 Planned | Threads and synchronization primitives (Standard edition) | ### Stability The current Standard edition is highly stable: - **unity branch**: fully compatible with Unity 2019.4.x – 6000.3.x LTS IL2CPP BCL, passing all (thousands of) test cases - **mono branch**: 99.95% compatible with Mono 4.8 BCL, with only one failing test case - **coreclr branch**: .NET 10 BCL support is in progress ## Editions LeanCLR provides **Standard** and **Core** editions: **Core is trimmed from Standard**. Both are implemented (single-threaded); full multi-threading for Standard remains on the roadmap. See [Core & Standard](https://doc.leanclr.com/docs/intro/editions). ### Core Edition The Core edition is implemented and runs on every platform with a C++11 toolchain. Core is designed as an embeddable pure scripting engine: you can run C# purely via the interpreter, or combine it with [LeanAOT](https://doc.leanclr.com/docs/aot/overview) to transpile hot IL to C++ for strong runtime performance. ### Standard Branches Standard is split by BCL source: | Branch | BCL Source | Notes | |------|------------|------| | **mono** | Mono BCL | General cross-platform integration; Mono 4.8 BCL compatible | | **unity** | Unity IL2CPP BCL | For Unity / Unity China integration | | **coreclr** | CoreCLR BCL | .NET 10 BCL support in progress | ### Standard vs Core | Feature | Standard | Core | | - | - | - | | ECMA-335 | Standard implementation, high compatibility | Standard ECMA-335 specification | | Thread model | Single-threaded (multi-threading planned) | Single-threaded | | Cross-platform | Windows, Linux, macOS, Android, iOS, HarmonyOS, WebAssembly, etc. | All platforms; pure C++11 with no platform-specific dependencies | | BCL | mono / unity / coreclr branches; platform icalls partially implemented | mono-4.5 BCL; only a subset of platform-related calls implemented | | GC | Precise Mark-Sweep full GC | Precise Mark-Sweep full GC | ## Demo ### leanclr-demo [leanclr-demo](https://github.com/focus-creative-games/leanclr-demo) provides two demos for quickly trying LeanCLR: | Demo | Description | |------|------| | **win64** | Windows x64 demo; run `run.bat` | | **h5** | WebAssembly browser demo; open `index.html` via an HTTP server | ### leanclr-unity-demo [leanclr-unity-demo](https://github.com/focus-creative-games/leanclr-unity-demo) shows how to use `leanclr-unity` to replace IL2CPP with LeanCLR when shipping to WebGL, mini-game, and Win64 targets. ## Related Repositories | Repository | Description | |------|------| | [leanclr-unity](https://github.com/focus-creative-games/leanclr-unity) | Unity plugin for LeanCLR; replace IL2CPP on WebGL / mini-game targets to reduce package size and memory usage | | [leanclr-godot](https://github.com/focus-creative-games/leanclr-godot) | LeanCLR Godot plugin (in development) | | [hybridclr](https://github.com/focus-creative-games/hybridclr) | **HybridCLR**: full-featured, low-overhead, high-performance C# hot-update solution for Unity | ## Contact - Email: leanclr#code-philosophy.com - Discord: - QQ Group: 1047250380