libxml++ is a C++ interface for working with XML files, using libxml
(gnome-xml) to parse and write the actual XML files. It has a simple
but complete API.

libxml++-5.0 (ABI version 5.0) does not depend on glibmm, is not as
good at handling UTF-8 strings, but has fewer dependencies.

See also: https://libxmlplusplus.sourceforge.net/