Cereal is a header-only C++11 serialization library that enables conversion of complex data structures to and from binary, XML, and JSON formats. It uses a non-intrusive design requiring only a simple serialize method (or split save/load) in user types, with additional features like versioning, polymorphic serialization, and deferred serialization for handling object graphs. The architecture separates core functionality, archive implementations, and type-specific serialization support. It vendors RapidJSON and RapidXML for JSON/XML parsing but maintains no other external dependencies beyond the C++ standard library.