The optical DWDM transmission systems can benefit from the SDN approach which was successfully demonstrated to be viable at the L2 and L3 layers. This poster describes a new generation of Czech Lightâ„¢ OpenDWDM devices which use NETCONF and YANG models as their northbound communication API. We are modernizing our system with the help of several open-source projects including Netopeer2, Sysrepo and Buildroot.