OpenDSA is a system for creating rich eTextbooks that combine quality text with visualizations and interactive, auto-graded exercises. As OpenDSA gains recognition, its use increases each year. This mandates a scalable, reliable, and sustainable infrastructure to accommodate the fast-growing demand for OpenDSA access.

We implemented OpenDSA-LTI, an interoperable infrastructure which transforms OpenDSA from a standalone, self-contained eTextbook to an integrated learning tool communicating with a Learning Management System (LMS) through the Learning Tool Interoperability (LTI) protocol. OpenDSA-LTI delivers OpenDSA content and interactive materials to students through a reliable and secure LMS interface. LTI integration encourages OpenDSA adoption by providing easy, intuitive tools that help instructors to build and generate OpenDSA eTextbooks in their LMS courses. OpenDSA-LTI allows OpenDSA content developers to take advantage of various tools already provided by the LMS instead of reproducing these through their own proprietary services.

The OpenDSA-LTI extendable design allows for adding new LTI-compliant exercises to OpenDSA books. This changes OpenDSA developers' efforts to searching for learning tools instead of reimplementing them. As an example, instead of maintaining the original OpenDSA programming evaluation engine, we could easily replace it with the Code Workout online drill-and-practice system.

Since its launch in August 2016 until June 2017, OpenDSA-LTI has hosted 36 active courses offered by 25 different universities in 6 countries, 41 instructors have used OpenDSA-LTI to host their courses on the Canvas LMS, and the system has 2,729 registered students.