Casperjs web service multithread

I am using a CasperJS script as a web service, accessing it from a node server. What I did not manage to do is to make Casper be 'multithread'. If I make two simultaneously requests to Casper from postman the result will be something scrambled between both requests for one response, and the second will be null. I saw that PhantomJS has a page principle, but I did not find anything similar for Casper.

Can i call Casper's web service with multiple requests at the same time and get correct/coherent responses?

Is there some configuration needed for the web server to allow me to do this?

Should the request be done in a 'special manner'? Are there any caveats regarding this that i should be aware of?

If it can only function sequentially, would starting multiple servers on the same machine but different ports solve the issue?

Here is the casper web service i am talking about. When I make a request like locahost:1338/?query=name.name it will crawl for that query on the specified url. My problem comes when I make 2 parallel requests with different queries.

    //includes web server modules
    "use strict";
    var port = 1338;
    var server = require('webserver').create();
    var url = 'url to scrap';

    //start web server
    var service = server.listen(port, function(request, response) {
        var arr1 = [];
        var arr2 = [];
        var arr3 = [];

        var casper = require("casper").create({
              verbose: true,
              logLevel: 'error',
              pageSettings: {
                loadImages: false,
                loadPlugins: false,
                userAgent: 'Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/49.0.2623.87 Safari/537.36'
              },
              clientScripts: ["vendor/jquery-1.12.1.js"]
        });

        casper.start(url, function() {
        }, function(){
            console.log(url + " not found");
            return;
        });

        casper.waitForSelector('.cssClass', function() {
        }, function(){
            console.log("not found");
            return;
        });

        casper.then(function() {
            var query = getQuery(request.url);
            casper.sendKeys('.cssClass', query);
            casper.click('.cssClass');

            casper.waitForSelector('.cssClass', function(){
                arr1 = this.evaluate(function(){
                    var nodeList = document.querySelectorAll(".cssClass");
                    return Array.prototype.map.call(nodeList, function(node){
                        return node.textContent;
                    });
                });
            }, function(){
                console.log("not found");
                return;
            });

            casper.then(function(){
                if(names.length > 0)
                {

                    casper.waitForSelector('.cssClass', function(){
                        arr2 = this.evaluate(function(){
                            var nodeList = document.querySelectorAll(".cssClass");
                            return Array.prototype.map.call(nodeList, function(node){
                                return node.textContent;
                            });
                        });
                        console.log("found");
                    }, function(){
                        console.log("not found");
                        return;
                    });

                    casper.waitForSelector('.cssClass', function(){
                        arr3 = this.evaluate(function(){
                            var nodeList = document.querySelectorAll(".cssClass");
                            return Array.prototype.map.call(nodeList, function(node){
                                return node.src;
                            });
                        });
                        console.log("found");
                    }, function(){
                        console.log("not found");
                        return;
                    });
                }
            });
        });

        casper.run(function() {
            response.statusCode = 200;
            response.write(JSON.stringify({p1: arr1, p2: arr2, p3: arr3}));
            response.close();              
        });
    });

    console.log('nServer running at http://localhost:' + port+'/');

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