Node.JS server with SystemD socket activation

nodejs.service

[Service]
ExecStart=/usr/bin/node /var/www/server.js
StandardOutput=syslog
StandardError=syslog
SyslogIdentifier=nodejs
User=www-data
Group=www-data

nodejs.socket

[Socket]
ListenStream=/var/run/nodejs.sock

[Install]
WantedBy=sockets.target

server.js

require('systemd');
require('autoquit');
var http = require('http'),
    express = require('express'),
    app = express();
app.get('/', function (req, res) {
    res.contentType('text/plain');
    res.send('Hello Express');
});
app.use(function(req, res, next) {
    res.status = 404;
    res.json({status: res.status});
});
app.use(function(err, req, res, next) {
    var status = err.status || err.statusCode || 500;
    res.status = status;
    res.json({status: res.status});
});
app.listen('systemd').autoQuit();