libcxxtools9v5 binary package in Ubuntu Bionic amd64

 cxxtools contains an argument-parser, a base-64 encoder/decoder, a
 C++ interface to iconv, md5-stream for easy MD5 calculation,
 threading classes, socket classes, a dynamic exception-safe buffer, a
 wrapper for dlopen/dlsym, a pool template (e.g., for a connection
 pool in a multi-threaded application), query_params, and a class for
 easy parsing of CGI parameters (GET and POST) in a CGI program.

Source package