Show HN: sy_callback.hpp – High-performance, header-only C++11 callback library

sy_callback.hpp is a header-only C++11 library designed to replace std::function with higher performance and smaller footprint.

Key features: - Supports static, member, global functions, capturing lambdas, and template functors. - Minimal size: 24 bytes for member/global callbacks; heap allocation only for arbitrary callables. - Benchmarks show faster call times and smaller memory usage compared to std::function. - Ideal for real-time systems, game engines, and performance-critical C++ code.

Examples and benchmarks are included in the README.