Something like in MongooseJS (please see examples given in the linked page):
// lib/thoonk.js
module.export = require('thoonk').createClient();
// config/dev.js
...
require('../lib/pubsub.js').open('localhost', '6379', 'dev');
...
// config/prod.js
...
require('../lib/pubsub.js').open('prod.server', '6379', 'prod');
...
And then, whenever we need thoonk, we can get it, fully ready just by requiring it:
// app.js
...
require('./config/' + process.env.NODE_ENV + '.js');
var thoonk = require('./lib/thoonk.js'); // ready-to-use!
...