garp.js

/**
 * A thin event-driven rpc system built with gun
 *
 * this implementation is bigger than it needs to be
 * but it does have some nice quality of life features
**/

var DEBUG = true; //Set to false if not debugging garp
	
class Rpc {
	constructor(gun, name) {
		this.gun = gun;
		this.name = (typeof name !== 'undefined') ? name : '';
		
		gun.on("opt", context => {
			this.validater(context);
		});
	}

	validater(ctx) {
		ctx.on("in", function (msg) {
			this.to.next(msg);
			
			if(DEBUG)
				console.log(msg);
		});
	}
}

if(typeof window == "undefined") {
	module.exports = {
		Rpc: Rpc,
	}
}

tester.js

//This is a basic and flexable test enviroment
var Gun = require("gun");

// Put Dev Dependencies Here
let Garp = require("./garp.js");
// end dev dependines

//Pre-Gun Stuff
let myRpc = new Garp.Rpc(Gun, "My Server"); // Create a new Garp Client/Server
//End Pre-Gun Stuff

var peers = []; //put the peers here

//peers.push("https://notabug.io/gun");

var gun = Gun({peers:peers});

//Start Tester code

//console.log(Garp);

//gun.get('aaaaaaaaaa').get("bbbbbbb").on(() => {});

gun._.on('out', {"asdf":"aaaaa"});

//gun.get("aaaaaaaaaa").get("bbbbbbb").put("aaaaaaaa");

As mentioned in Gitter;

This line:
let myRpc = new Garp.Rpc(Gun, "My Server"); // Create a new Garp Client/Server

Should be
let myRpc = new Garp(Gun, "My Server"); // Create a new Garp Client/Server