&gt; The window is closing to declare PyPy the successor to CPython2<p>PyPy is <i>much</i> more than Python + JIT. It&#x27;s a whole framework for writing interpreters in Python, with the bonus that any interpreter you build gets an awesome JIT for free. I whipped up a brainfuck interpreter in a few lines of RPython, and bam I have a compiled executable that JIT compiles my brainfuck on the fly.<p>You can build interpreters for Ruby, PHP, whatever language you want. There is no window running out for that and that&#x27;s the best bit of PyPy. The fact the flagship implementation for this framework is a Python interpreter is cool but not the only or coolest bit about the project - it&#x27;s so much more.