Programmable circuits and electrically triggered traps/defense mechanisms

Scenario 1:

Imagine that you've built an awesome fort. You've fortified it with steel/concrete or whatever else we'll be able to build with, and now it's night, and zombies/other players are attacking. Your only defense is setting up lookouts and shooting the zombies. (And whatever else has already been planned)

Scenario 2:

Imagine that you've built an awesome fort. You've fortified it with steel/concrete or whatever else we'll be able to build with, and now it's night, and zombies/other players are attacking. Luckily, the infrared sensors you set up in the forest picked up a signal, which was sent to a microcontroller/computer, which sent a signal to initiate a lockdown-sequence that locked all exits and armed the minefield you've set up surrounding the fort. Then, a silent alarm was triggered in the fort, alarming all available units of the impeding attack, so they can assume their positions.

I'm not saying it should be easy to set up (in fact, I think it would be awesome if it was kind of like redstone in minecraft), but I really think it would add an enormous strategic aspect to building a fort and crafting in general, and I think it creates a lot of variation in what you can expect when trying to take over a fort.

Another aspect of this is, that it would make the people in the fort feel "secure", so if the attackers manage to avoid all sensors, they would be able to attack with an enormous element of surprise.

What does everyone else think of a system like this?