Something a little different here, I picked a card from a Tarot Deck (Queen of Disks) and tried to use it to solve computer problem. The Capsule Reviews Promise to Keep It Short™ is still in effect.
Disks represent the manifest, physical, and real. The queens of the Tarot represent folks who can teach us about the reflexive and universal aspect of computing. So the Queens are concerned with compilers and metaprogramming, but the suit of disks is concerned with electricity and heat and bandwidth and billing. The security engineer is tasked with managing the conflict when a group of people with norms and policies and expectations and who-should-do-what-when tries to make use of a universal machine.
Limit your attackable surface in your designs. Work with reviewers. Remember that you’re working together toward the same goal. Be aware of the complexities of your policy and use cases: complex realities require complex systems. Debug the real world first.