Node server stub overrides my existing routes

Hello there!

I have the following scenario:

• Existing Node + Express app.
• Existing routes in place.
• Integrating the auto-generated Node stub for my API.

I have modified the startup code to merge it with my existing Express app:

// Swagger stuff ***********************************
var oas3Tools = require('oas3-tools');

// swaggerRouter configuration
var options = {
    controllers: path.join(__dirname, './API/controllers'),
};

var expressAppConfig = oas3Tools.expressAppConfig(path.join(__dirname, './API/api/openapi.yaml'), options);
// expressAppConfig.addValidator();
const app = expressAppConfig.getApp();

const CONSTANTS = require('./CONSTANTS.js');
const initializer = require('./initializer.js');
const utils = require('./utils/utils.js');

// Start up stuff ***********************************
// const app = express();
const http = require('http').createServer(app);

Then, my old routes stopped working!

It seems to be either serving the API or my old routes, depending on commenting / uncommenting this line:

// expressAppConfig.addValidator();

Is there a way to have both routes served from the same app?

Thanks in advance for your support!