Getting Started

What is PyPy ?

In common parlance, PyPy has been used to mean two things. The first is the RPython translation toolchain, which is a framework for generating dynamic programming language implementations. And the second is one particular implementation that is so generated – an implementation of the Python programming language written in Python itself. It is designed to be flexible and easy to experiment with.

This double usage has proven to be confusing, and we are trying to move away from using the word PyPy to mean both things. From now on we will try to use PyPy to only mean the Python implementation, and say the RPython translation toolchain when we mean the framework. Some older documents, presentations, papers and videos will still have the old usage. You are hereby warned.

We target a large variety of platforms, small and large, by providing a compiler toolsuite that can produce custom Python versions. Platform, memory and threading models, as well as the JIT compiler itself, are aspects of the translation process - as opposed to encoding low level details into the language implementation itself. more...

Just the facts

Download a pre-built PyPy

The quickest way to start using PyPy is to download a prebuilt binary for your OS and architecture. You can either use the most recent release or one of our development nightly build. Please note that the nightly builds are not guaranteed to be as stable as official releases, use them at your own risk.

Installing PyPy

PyPy is ready to be executed as soon as you unpack the tarball or the zip file, with no need to install it in any specific location:

$ tar xf pypy-2.1.tar.bz2
$ ./pypy-2.1/bin/pypy
Python 2.7.3 (480845e6b1dd, Jul 31 2013, 11:05:31)
[PyPy 2.1.0 with GCC 4.4.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
And now for something completely different: ``PyPy is an exciting technology
that lets you to write fast, portable, multi-platform interpreters with less

If you want to make PyPy available system-wide, you can put a symlink to the pypy executable in /usr/local/bin. It is important to put a symlink and not move the binary there, else PyPy would not be able to find its library.

If you want to install 3rd party libraries, the most convenient way is to install distribute and pip:

$ curl -O
$ curl -O
$ ./pypy-2.1/bin/pypy
$ ./pypy-2.1/bin/pypy
$ ./pypy-2.1/bin/pip install pygments  # for example

3rd party libraries will be installed in pypy-2.1/site-packages, and the scripts in pypy-2.1/bin.

Installing using virtualenv

It is often convenient to run pypy inside a virtualenv. To do this you need a recent version of virtualenv – 1.6.1 or greater. You can then install PyPy both from a precompiled tarball or from a mercurial checkout:

# from a tarball
$ virtualenv -p /opt/pypy-c-jit-41718-3fb486695f20-linux/bin/pypy my-pypy-env

# from the mercurial checkout
$ virtualenv -p /path/to/pypy/pypy/translator/goal/pypy-c my-pypy-env

Note that bin/python is now a symlink to bin/pypy.

Clone the repository

If you prefer to compile PyPy by yourself, or if you want to modify it, you will need to obtain a copy of the sources. This can be done either by downloading them from the download page or by checking them out from the repository using mercurial. We suggest using mercurial if one wants to access the current development.

You must issue the following command on your command line, DOS box, or terminal:

hg clone pypy

This will clone the repository and place it into a directory named pypy, and will get you the PyPy source in pypy/pypy and documentation files in pypy/pypy/doc. We try to ensure that the tip is always stable, but it might occasionally be broken. You may want to check out our nightly tests: find a revision (12-chars alphanumeric string, e.g. “963e808156b3”) that passed at least the {linux32} tests (corresponding to a + sign on the line success) and then, in your cloned repository, switch to this revision using:

hg up -r XXXXX

where XXXXX is the revision id.

Where to go from here

After you successfully manage to get PyPy’s source you can read more about:

Understanding PyPy’s architecture

For in-depth information about architecture and coding documentation head over to the documentation section where you’ll find lots of interesting information. Additionally, in true hacker spirit, you may just start reading sources .

Filing bugs or feature requests

You may file bug reports on our issue tracker which is also accessible through the ‘issues’ top menu of the PyPy website. Using the development tracker has more detailed information on specific features of the tracker.