User blog comment:ChaosEnforcer/Geth Reaper code/@comment-4950455-20121026230811/@comment-4973403-20121027182647

With the original Reaper code, the geth were still multiple programs running in a hardware body. however, once the Reaper Code was modified by Legion/Geth VI each hardware body joined all of the geth programs into individual personalities granting them a more individualistic identity. Though they apparently can still transfer their programing into other units as Tali mentions that geth are interacting with the quarian enviro-suits to assist them in re-building their immune systems.