Project Structure

This document describes the directory structure and organization of the LeanCLR project.

Overview

leanclr/
├── src/
│   ├── runtime/      # LeanCLR runtime core
│   ├── libraries/    # Base class libraries
│   ├── tools/        # Command-line tools
│   ├── samples/      # Sample projects
│   └── tests/        # Unit tests
├── docs/             # Documentation
└── tools/            # Build utilities

Note: Demo examples have been moved to a separate repository: leanclr-demo

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src/runtime (Runtime Core)

Directory: src/runtime

Core implementation of the LeanCLR runtime. This is the heart of the project.

Directory	Description
metadata	ECMA-335 metadata parsing and representation
vm	Virtual machine core (type system, method invocation, runtime state management)
interp	IL interpreter and IR interpreter implementation
gc	Garbage collector (in development)
icalls	Internal calls implementation
alloc	Memory allocators (metadata allocation, managed object allocation)
intrinsics	Intrinsic method implementations
os	OS abstraction layer
utils	Utility functions and helpers
misc	Miscellaneous components

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src/libraries (Base Class Libraries)

Directory: src/libraries

Contains .NET Framework base class libraries required by the runtime:

• mscorlib.dll - Core runtime library
• System.dll - System namespace types
• System.Core.dll - LINQ and additional system types

Note: Only .NET Standard 2.x / .NET Framework 4.x core libraries are verified.

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src/tools (Command-Line Tools)

Directory: src/tools

lean

A command-line tool with embedded LeanCLR runtime that can directly load and run .NET assemblies.

Basic Usage:

lean [options] <dll_name> [-- <dll_args>...]

Options:

Option	Description
-l, --lib-dir <dir>	Add a DLL search path (can be used multiple times)
-e, --entry <entry>	Specify entry method in format Namespace.Type::Method
-h, --help	Display help information

Example:

lean -l dotnetframework -l libs CoreTests -e test.App::Main

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src/samples (Sample Projects)

Directory: src/samples

Project	Description
startup	Win64 native platform sample project
lean-wasm	WebAssembly platform sample project

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src/tests (Unit Tests)

Directory: src/tests

Unit test framework and test cases for the LeanCLR runtime.

Directory	Description
basic_test_runner	C++ test runner (loads and executes managed test assemblies)
managed	C# managed test projects

See Test Framework Documentation for details on how to add test cases.

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docs (Documentation)

Directory: docs

Project documentation including build guides, embedding instructions, and API references.

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tools (Build Utilities)

Directory: tools

Build and development utilities:

• clang-format - Code formatting configuration