...It evaluates both conformance and performance, which helps avoid treating speed as meaningful when a library does not parse or generate JSON correctly. The benchmark measures areas such as parsing speed, generation speed, memory use, and code size across many open-source libraries. It includes test data and JSON standard checks so implementations can be compared under more consistent conditions. The project is useful for library authors, C++ developers, and performance-focused engineers choosing a JSON implementation. Its main value is providing a transparent reference point for understanding tradeoffs among native JSON libraries.