The open LMS by Instructure, Inc.
an example of using LTI and the Outcomes Service in Instructure Canvas
LTI template written in Ruby on Rails. Quickly create a new application that can be launched through your Learning Management System using the LTI protocol.
A Ruby library for the Canvas API (and code generator for other languages, eventually)
Multiplayer "Snake" game using Ruby, MongoDB, WebSockets, and HTML canvas.