The Cxx dual library, or CXXD for short, is a C++ macro header-only library which chooses between using a Boost library or its C++ standard equivalent library for a number of different C++ implementations, while using the same code to program either choice. An 'implementation', called a 'dual library', is a Boost library which has a C++ standard library equivalent whose public interfaces are nearly the same in both cases. I have updated the Cxx dual library, for those who prefer to minimize their use of macros in source code, by providing an alternate method to the use of macros for including the appropriate header files and specifying the appropriate namespace for a dual library. In this alternate method including the appropriate header files is done by including an implementation header file, and specifying the appropriate namespace is done by using a C++ namespace alias. The alternate method, called the alias mode, is fully documented. You can get the latest version of the Cxx dual library at https://github.com/eldiener/cxx_dual. Instructions for using the library are in the README.md file. PDF documentation is available in cxx_dual.pdf, HTML doc is availavble online at http://eldiener.github.io/cxx_dual and you can generate local HTML documentation using the doc jam file. Questions, comments, bug reports are always welcome.