Using Peer Code Reviews to Scale a Brownfield Software Engineering Course

Abstract

Peer code reviews involve students conducting a code review of a classmate's submission to a programming assignment. While peer code reviews have an established history of being used and studied in computing education, they have primarily been documented in introductory computing courses. This experience report describes how we implemented peer code reviews in an upper-division software engineering course that focuses on making modifications to large, existing code bases (i.e., brownfield development). We discuss the perceived learning benefits, perceived challenges, and agreement between peer and course staff reviews. Overall, students enjoyed being able to see different approaches to the programming task they had just submitted, but expressed concerns about feeling qualified to make effective peer code reviews due to their limited software engineering experience and the difficulty of assessing code design. We also find that students are capable of evaluating the functional correctness of their peer's submission, but struggle to give accurate assessments of their peer's design and code style. We conclude with recommendations specifically for instructors who wish to use peer code reviews in upper-division software engineering courses, such as using a structured template to scaffold the peer code reviews and allowing multiple opportunities to provide code reviews to improve students' self-efficacy.