NACTF is a Capture The Flag (CTF) cybersecurity competition for middle and high school students, entirely run by 2 of my friends and I. The competition had a prize pool of $800, ran for 5 days, and attracted over 1300 participants.
I was responsible for administrating the challenge servers that all of the participants would connect to. The challenges ran in a Kubernetes cluster, with configuration available on our GitLab repositories. In addition, I was a challenge author (some of which are available here).