+ For Debian-based systems, the official ``libyang`` package requires recent
+ versions of ``swig`` (3.0.12) and ``debhelper`` (11) which are only
+ available in Debian buster (10). However, ``libyang`` packages built on
+ Debian buster can be installed on both Debian jessie (8) and Debian stretch
+ (9), as well as various Ubuntu systems. The ``python3-yang`` package will
+ not work, but the other packages (``libyang-dev`` is the one needed for FRR)
+ will.