You should warn clearly that this implementation of ECC point multiplication is not secure at all regarding side-channel attacks (power, EM/RF emissions, memory read), and timing measurements. Depending of the bits of the scalar number (usually a private secret), the operations performed are very different.
https://github.com/albertobsd/ecctools/blob/main/gmpecc.c#L99

All the operations requiring this point multiplication are affected and are not secure. Public key computation (with keygen, or calculatefromkey) and sharedsecret ECDH.

This should not be used in any system in production, or securing a private key.