Containerizing CS50

We argue in favor of Docker containers as alternatives to clusters of servers or virtual machines for students in introductory programming courses. We present our experience with the same since 2015 in CS50 at Harvard University as well as the pedagogical and operational motivations therefor. We present, too, the evolution of our environments for students over the years, from an on-campus cluster, to an off-campus cloud, to client-side virtual machines, to Docker containers, discussing the trade-offs of each. Not only do containers provide students with a standardized environment, reducing technical difficulties and frequently asked questions at term's start, they also provide instructors with full control over the software in use and versions thereof, additionally allowing instructors to deploy updates mid-semester. Particularly for large courses with hundreds or even thousands of students, containers allow staff to focus more of their time on teaching than on technical support. And, coupled with text editors that support extensions or plugins, containers allow instructors to optimize students' environment for learning, while still acquainting students with industry-standard tools. Most recently implemented atop GitHub Codespaces, a cloud-based version of Visual Studio Code, our own container-based solutions have since been used by more than 700,000 students and teachers, both on campus and off, and are also freely available to any teacher or student outside of our own university. *** This is CS50, Harvard University's introduction to the intellectual enterprises of computer science and the art of programming. *** HOW TO SUBSCRIBE http://www.youtube.com/subscription_center?add_user=cs50tv HOW TO TAKE CS50 edX: https://cs50.edx.org/ Harvard Extension School: https://cs50.harvard.edu/extension Harvard Summer School: https://cs50.harvard.edu/summer OpenCourseWare: https://cs50.harvard.edu/x HOW TO JOIN CS50 COMMUNITIES Bluesky: https://bsky.app/profile/cs50.h