[Suicide Junkie]

Weapon platforms sit in a planet's cargo space.
They will give the planet extra hitpoints, and weapons which it can fire out into space.

The only way to get platforms at a warppoint, is to have a planet on top of the warppoint.
With Warppoint openers, you can easily do that.

Only one platform per planet needs combat sensors and ECM, since a stack of platforms will share the bonus.