Erro ao criar middleware

custom-express.js :

require('marko/node-require').install()
require('marko/express')

const express = require('express')
const app = express()
const bodyParser = require('body-parser');

app.use(bodyParser.urlencoded({
    extended: true
}));

const routes = require('../app/routes/routes')
routes(app)

module.exports = app

package.json

{
  "name": "casa-codigo",
  "version": "1.0.0",
  "description": "projeto node da alura",
  "main": "server.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1",
    "start": "nodemon server.js --ignore *.marko.js"
  },
  "author": "Igor Gomes",
  "license": "ISC",
  "dependencies": {
    "body-parser": "^1.19.0",
    "express": "4.16.3",
    "marko": "^4.13.4-1",
    "mysql": "^2.18.1",
    "sqlite3": "^4.1.1"
  },
  "devDependencies": {
    "nodemon": "^1.18.4"
  }
}

obs: Na aula pede ser a versão 1.18.3 do body-parse mas mesmo com ela não funciona

erro:

events.js:298
      throw er; // Unhandled 'error' event
      ^

Error: listen EADDRINUSE: address already in use :::3030
    at Server.setupListenHandle [as _listen2] (net.js:1309:16)
    at listenInCluster (net.js:1357:12)
    at Server.listen (net.js:1445:7)
    at Function.listen (/home/igor/Alura/Node/CasaCodigo/node_modules/express/lib/application.js:618:24)
    at Object.<anonymous> (/home/igor/Alura/Node/CasaCodigo/server.js:3:5)
    at Module._compile (internal/modules/cjs/loader.js:1144:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1164:10)
    at Module.load (internal/modules/cjs/loader.js:993:32)
    at Function.Module._load (internal/modules/cjs/loader.js:892:14)
    at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:71:12)
Emitted 'error' event on Server instance at:
    at emitErrorNT (net.js:1336:8)
    at processTicksAndRejections (internal/process/task_queues.js:84:21) {
  code: 'EADDRINUSE',
  errno: -98,
  syscall: 'listen',
  address: '::',
  port: 3030
}
[nodemon] app crashed - waiting for file changes before starting...