UCTF is a platform for hosting capture-the-flag competitions without building the infrastructure yourself. It grew out of two events we ran on our own Kubernetes cluster: organisers kept needing the same things, so I turned them into a product — managed CTFd, challenges that can be instanced per team, and a deployment pipeline that follows a git repository.

Features

• Managed CTFd instance, with themes and plugins delivered for you
• Shared and per-team instanced challenges, spun up on demand
• Git-synced challenge delivery straight from a GitHub repository
• Bring your own container images, so nothing is locked to the platform
• Custom domain with TLS and 10 GB of included storage
• Discord and generic webhooks, plus CTFtime support

Technologies Used

• Kubernetes for scheduling the short-lived challenge instances
• Go for the instancer and the control plane
• CTFd as the scoreboard and player-facing platform
• Container registries and git as the delivery path for challenges

Two write-ups cover the events behind it: How (not) to host your CTF on the first one, and Universal CTF: 32 hours in data on the second, which ran 608 players and 3,807 throwaway pods on this platform.