fastmcpp (MeshInspector fork)

This is MeshInspector's fork of 0xeb/fastmcpp, a C++ port of the Python fastmcp library. It is used by MeshLib.

For documentation, features, examples and the API, see the original repository. This README only lists how the fork differs from it.

Base

The fork branched from upstream at 9afa99f (2026-03-18, fastmcpp 3.1.0). Later upstream changes (parity with fastmcp 3.3 / 3.4, streamable-HTTP CORS and DELETE, FASTMCPP_ENABLE_OPENSSL, the _meta passthrough fix, ...) are not merged here.

Differences from upstream

Build and packaging

• The library can be installed with CMake: install() exports the fastmcpp::fastmcpp_core target and a fastmcppConfig.cmake for find_package(fastmcpp).
• nlohmann_json and cpp-httplib are found with find_package instead of being fetched with FetchContent.
• New option FASTMCPP_DEPS_ADD_SUBDIRECTORY (default OFF): take both dependencies' headers from sibling directories (../nlohmann-json, ../cpp-httplib) instead of find_package.
• The version is hard-coded in include/fastmcpp/version.hpp, not passed from CMake.
• The fastmcpp CLI executable is built only with FASTMCPP_BUILD_TESTS.
• On non-MSVC compilers fastmcpp_core is compiled with -fvisibility=hidden -fvisibility-inlines-hidden, matching consumers built with hidden visibility (avoids ld64 weak-symbol warnings).
• fastmcpp_core follows BUILD_SHARED_LIBS; the shared library exports only what is marked with FASTMCPP_API / FASTMCPP_CLASS (include/fastmcpp/export.hpp).
• fastmcpp_core links ${CMAKE_DL_LIBS} for dlopen (needed before glibc 2.34).

Compiler compatibility

• Fixes for GCC 11, Visual Studio 2022, older Xcode, Clang and Apple Silicon builds.
• A libc++ workaround (include/fastmcpp/clang.hpp), injected as a precompiled header under Clang and AppleClang on Apple platforms.
• Compatibility with newer cpp-httplib versions.

Behavior

• std::filesystem is used through its non-throwing (std::error_code) overloads.

API additions

• SseServerWrapper::add_route(method, path, handler) registers custom HTTP routes (GET, POST, PUT, DELETE) next to the built-in /sse and /messages endpoints. It must be called before start(). Tested in tests/server/sse_add_route.cpp.

License

Same as upstream, see LICENSE.