Hi Scott. We're not using PEAR.

If you are interested in looking at the implementation and other interesting security stuff, we have a lot of security openings:

Security Software Engineer - https://www.facebook.com/careers/department?req=a0IA000000G2...

Open Source Security Engineer - https://www.facebook.com/careers/department?req=a0I1200000G4...

PrivateCore Software Engineer - https://www.facebook.com/careers/department?req=a0I1200000G4...

Security Infrastructure - https://www.facebook.com/careers/department?req=a0IA000000G4...