It seems there is a(n older) 'Cantor with the sygnm backend' in the wild: https://git.sygnm.org/sygnmdev/cantor-sygnms However, Cantor is the KDE project now, and I couldn't find any reference to 'Syg…". If anybody could offer a comment in relation with the above, it would be nice.
Looks like sygnm is computer algebra framework and its author have decied to create sygnm backend for Cantor, but he have stop development of the Cantor sygnm backend and sygnm framework about 8 months ago. We, Cantor dev team, if I am not mistaken, haven't contacts with sygnmdev (the author of sygnm) before and haven't know about sygnm backend development