C-sigma: Easy-to-use Sigma proofs in C using libsodium
github.comNice, not sure origin of term Sigma here, it isn't the Hugo Krawcyzk family of SIGMA (SIGn & MAc) protocols.
It is because SIGMA protocols diagrams, as used in zero knowledge, kind of look like a capital greek sigma. It is not related to the other sign & MAC protocol.
It is a letter of the greek alphabet.