Hi Niels, I have sent a new version of ecc-sm2 realization patch cause that I'm not sure which git repository should I commit (gitlab or github?). I have tried the ecc_mod_inv and it works well in FP. Where should I commit my patch? The access request to fork in Nettle / nettle * GitLab (liu.se)https://git.lysator.liu.se/nettle/nettle was denied. Best regards