THE BioSPI SYSTEM FOR SIMULATION OF BIOCHEMICAL PROCESSES. BioSPI is a computer application we have developed for simulating the behavior of biochemical systems specified in the pi calculus. It is based on the Logix system, which implements Flat Concurrent Prolog (FCP). The use of FCP allows both mobility and synchronized communication, two of the major features of the pi-calculus. To the best of our knowledge this is the only implementation of the full synchronous calculus, including mixed choice.