ECDSA Secp256k1 curve operations.

By default erlang’s :crypto.verify is used to make it less problematic when using as a library (no need for gcc).

However, if :libsecp256k1 NIF is available, it’s used. To enable it just uncomment appropriate line in mix.exs deps.

libsecp256k1: https://github.com/bitcoin-core/secp256k1

If gcc and git dependencies are not a problem, use NIF. It’s much faster and it’s the proper way to do it consensus-wise. Do note that even though it seems unlikely, an error in the NIF will bring the whole erlang VM down (not just the process)