The GitHub repository contains a platform that performs Non-Binary Low-Density Parity-Check (NB-LDPC) sum-product decoding, both flooding and layered. It uses Fast Fourier Transform-QSPA (FFT-QSPA) developed by MacKay and Davey with 2,3 values in the first parameter, as well as majority decoding with 3,4 values.
The use of FFT allows for different prime sizes up to 1024.