CXXStateTree – A modern C++ library for hierarchical state machines

In plain words

CXXStateTree is a header-only C++ library for building hierarchical state machines with clean APIs. It enables developers to create deeply nested states with entry and exit handlers, transitions guarded by conditions, and asynchronous operations using C++20 coroutines. The library includes optional runtime type identification for flexibility. It targets software engineers working on complex control logic in embedded systems, games, robotics, and other applications requiring finite state machines.

written from the facts on this page · September 2026

From the sources

A C++ Header-Only Hierarchical State Tree Library. Contribute to ZigRazor/CXXStateTree development by creating an account on GitHub.

# include < iostream > # include " CXXStateTree/StateTree.hpp " using namespace CXXStateTree ; int main () { auto machine = StateTree::Builder () . initial ( " Idle " ) . state ( " Idle " , [](State& s) { s. on ( " Start " , " Running " , nullptr , []() { std::cout << " Idle -> Running " << std::endl; }); }) . state ( " Running " , [](State& s) { s. on ( " Stop " , " Idle " , nullptr , []() { std::cout << " Running -> Idle " << std::endl; }); }) . build (); machine. send ( " Start " ); machine. send ( " Stop " ); } 🛠️ Building Shared Library cmake -S . -B build cmake --build build After these command the Shared Library can be found in build directory cmake -S . -B build…from github.com

In the maker’s words, at launch

Hi HN! I've built [CXXStateTree](https:&#x2F;&#x2F;github.com&#x2F;ZigRazor&#x2F;CXXStateTree), a modern C++ header-only library to create hierarchical state machines with clean, intuitive APIs. It supports: - Deeply nested states - Entry&#x2F;exit handlers - State transitions with guards and actions - Asynchronous…

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