At Purdue, REST APIs are used for both internal and third-party vendor applications. Internally they are used for syncing data between SIS and Blackboard Learn. Externally, they perform data exchanges with a few third-party vendors. Hear about lessons learned while creating REST applications, such as unexpected user record updates, managing daily API call limitation, and how to handle exceptions during REST API calls. In addition, best practices for handling token expiration and creating a wrapper around REST APIs will be discussed.