Antonio Cuni - Python and PyPy performance (not) for dummies In this talk we would like to have a short introduction on how Python programs are compiled and executed, with a special attention towards just in time compilation done by PyPy. PyPy is the most advanced Python interpreter around and while it should generally just speed up your programs there is a wide range of performance that you can get out of PyPy, ranging from slightly faster than CPython to C speeds, depending on how you write your programs. We will split the talk in two parts. In the first part we will explain how things work and what can and what cannot be optimized as well as describe the basic heuristics of JIT compiler and optimizer. In the next part we will do a survey of existing tools for looking at performance of Python programs with specific focus on PyPy. As a result of this talk, an audience member should be better equipped with tools how to write new software and improve existing software with performance in mind. The talk will be given by Antonio Cuni and Maciej Fijalkowski, both long time PyPy core developers and expert in the area of Python performance.