Congo is the MongoDb Explorer written by @robconery as part of Tekpub's Backbone.serie and now available on Pluralsight course https://app.pluralsight.com/library/courses/playing-with-backbonejs/
The original application : https://github.com/robconery/congo
If you follow the Pluralsight course with the most recent versions of Backbone, Mongoskin and Marionette you will quickly run into trouble as those libraries has evolved over time. Unfortunatelly, the application on Rob's repository was not upgraded since then.
While I was fallowing the course, I've upgraded parts of the application to use the newest Backbone.js v1.3.3 at this time. Also updating parts of Mongoskin as access to MongoDb has slightly changed.
There is no code for MarionetteJS part in Rob's repo. I've implemented it following the last section using the latest MarionetteJS v3.3.1, but there were some noticable differences between the current version and one used in the videos.
As I said most important changes were in BackboneJS and MarionetteJS but also many changes were done to Mongoskin and Express. I've also replaced Jade view engine by Pug with some minor changes in the syntax.
Enjoy !