I Thought Cypress Wood Did Not Rot?

[swamp snorkler]

My uncle made me a swing out of cypress about 9 years ago. Well where the bottoms bolt together its all rotted out. Could it be the hardware he used that caused this? None of the slats or the arm rest were rotten. Just where he had things bolted together? I'm confused. Anyway, I took it all apart, saved the chain and the slats and I have a buddy that has some cypress that he's going to give me to make a new one. I saved the pieces that were rotting and I'll use that to make a pattern.

What kind of hardware should I use to bolt it back together?