Thanks. This is still on my radar, but I've been quite busy ^. I've read the code, and it's indeed quite entangled with gpg semantics. I was trying to figure out and propose some new interface, but I got a bit stuck and put that at rest for awhile.
My current idea is to take a more thorough look at pacman code itself to see how it could/would use that interface, which hopefully will give me some ideas. No idea when I'll work on that though. Cheers, -- Max Gautier
