This is a ethereum RPC library written in c++20.
//Assuming a client like geth or a test client like hardhat is running.
import ETH.RPC;
int main()
{
using RPC = ETH::RPC::RPC;
//creating an rpc instance connecting to localhost on port 8545
RPC rpc("127.0.0.1", "8545");
}//returns the client version
rpc.Web3ClientVersion();
//returns the sha3 of a given input
rpc.Web3Sha3();