Source Code Tales Tamás Szelei's coding blog

Introducing rpclib

The 361st commit in the rpclib repository marks the first public release of rpclib, the project I’ve been working for the last ~11 months (294 days, to be exact). What started off as “throw this together in a month and then move on to the next thing” became a crazy journey of perfectionism and “I’ll add this tiny feature before release because what would people think if it’s not there”. Breaking and reworking things just for the sake of it. That’s a great way to have a side project to work on, but not a great way to finish it.

I realized this about a month and a half ago and since then, I’ve been working towards a complete state that I can release. Right now I’m minutes away from pushing the button to upload the 1.0.0-preview1 release. I decided to create a preview before the actual release, because at this point feedback is pretty important.

What is rpclib?

In short, rpclib is a modern msgpack-rpc library for C++. It grew out of the frustration over the boilerplate or external tooling that many RPC solutions require. Its syntax was inspired by Boost.Python and luabind. I wanted something that would have minimal setup code and a similar “binding” logic as those libraries. rpclib does not operate with “services”, it does the bare-bones of RPC: exposing a function for remote calling.

So this is the syntax of the server:

#include <iostream>
#include "rpc/server.h"

void foo() {
    std::cout << "foo was called!" << std::endl;

int main(int argc, char *argv[]) {
    // Creating a server that listens on port 8080
    rpc::server srv(8080);

    // Binding the name "foo" to free function foo.
    // note: the signature is automatically captured
    srv.bind("foo", &foo);

    // Binding a lambda function to the name "add".
    srv.bind("add", [](int a, int b) {
        return a + b;

    // Run the server loop.;

    return 0;

The client is implemented in the same spirit. Only the most basic “setup” code is there and the rest is your applicaton logic (i.e. calling functions):

#include <iostream>
#include "rpc/client.h"

int main() {
    // Creating a client that connects to the localhost on port 8080
    rpc::client client("", 8080);

    // Calling a function with paramters and converting the result to int
    auto result ="add", 2, 3).as<int>();
    std::cout << "The result is: " << result << std::endl;
    return 0;

Where to get it

You can find the project on github: rpclib. The documentation is on If you have any questions, gitter is here: rpclib gitter. All feedback is welcome!