t.js

var express = require('express');

var app = express();

app.set('env', 'production');

app.get('/', function(req, res) {
    throw new Error('dsjldsl');
});

app.use(logErrors);
function logErrors(err, req, res, next) {
    res.send(500, 'Something broke!');
}

app.listen(3000);