The report will tell about software developing working on high speeds and having the predictable reaction time. Also there will be presented the Python integration ways with ctypes and cython with the high-speed services of the operation system. It will touch upon the questions of memory, processes, streams, fibers and GIL managingcontrol. The audience will learn how to build systems with the expected reaction time. The knowledge can be used for servers’ development servicing a lot of clients simultaneously or executing high-speed data processing.