'''[http://pypy.org/%|%pypy]''' is a fast, compliant alternative implementation of [Python], and also a toolkit for creating dynamic language interpreters. ** Reference ** [http://tratt.net/laurie/blog/entries/fast_enough_vms_in_fast_enough_time%|%Fast Enough VMs in Fast Enough Time], Laurence Tratt, 2012-02-08, 2012-02-07: [http://research.microsoft.com/apps/video/default.aspx?id=144687&r=1%|%PyPy's Approach to Implementing Dynamic Languages Using a Tracing JIT Compiler], [http://cfbolz.de/%|%Carl Fridrich Bolz], 2011-01-31: [http://morepypy.blogspot.com/2011/04/tutorial-writing-interpreter-with-pypy.html%|%Writing an Interpreter with PyPy, Part 1], Andrew Brown: ** Language Implementations ** [http://www.stups.uni-duesseldorf.de/w/A_Javascript_Interpreter_in_RPython%|%A Javascript Interpreter in RPython], stephan Zalewski: [http://convergepl.org/%|%Converge]: a dynamically-typed [object orientation%|%object-oriented] [programming language] with compile-time metaprogramming facilities. Put simply, Converge has a macro-like facility that can embed domain specific languages with arbitrary syntaxes into source files. [https://github.com/diiq/oyoy%|%Oyster]: [Lisp] [pypy]: [Python] [https://bitbucket.org/cfbolz/pyrolog%|%Pyrolog]: [Prolog] [https://bitbucket.org/pypy/lang-smalltalk%|%Spy]: [Smalltalk]/[Squeak] [http://www.topazruby.om%|%Topaz]: [Ruby] ** Description ** pypy provides the ability to run untrusted code in a fully secure way. It also supports ''stackless mode'', providing micro-threads for massive concurrency. pypy interpreters are written in [Rpython] <> Python