# Boost.Compat Boost.Compat is a repository of C++11 implementations of standard components added in later C++ standards. Its target audience is Boost library authors whose libraries support a lower C++ standard, but wish to utilize a component added in a subsequent one. The criteria for inclusion in Boost.Compat are as follows: * The implementation should be relatively simple and header-only. * The component must implement the standard functionality exactly, without deviations or extensions. This allows (but does not require) the implementation to be a simple `using` declaration in case the standard component is available. * The component must not depend on any Boost libraries except Boost.Config, Boost.Assert, or Boost.ThrowException. * The component must not be a vocabulary type, visible in the library APIs. The user should never see a `boost::compat` type; the use of Compat types should be confined to library implementations.