APED: "security"

My moat is deep and acid-filled
and lined with razor blades.
And boiling oil or LN2
spills from my balustrades.
My automatic shotguns are
tripped by electric eyes,
and there's no way to get around:
they're pointed to all sides.
My drawbridge: lined with armor plate,
just like all the walls,
and if someone should try to climb?
That's where my cobras crawl.
It's the safest house that ever was
and gives me joy and pride --
except that I forgot my keys,
and now I'm locked outside.