For more info, see https://github.com/lastfm/last.json
lastjson is a header only C++ library that can parse JSON strings into objects of type lastjson::value and stringify those objects, but also native C++ types, to JSON formatted data. The design rationale was to have lightweight JSON value objects, that can be passed by value, and to offer a natural interface to working with JSON values.