# PyPy directory cross-reference

Here is a fully referenced alphabetical two-level deep directory overview of PyPy, plus some relevant top-level directories:

Directory | explanation/links
--- | ---
source pypy/bin/ | command-line scripts, mainly source pypy/bin/pyinteractive.py
source pypy/config/ | handles the numerous options for building and running PyPy
source pypy/doc/ | text versions of PyPy developer documentation
source pypy/doc/config/ | documentation for the numerous translation options
source pypy/doc/discussion/ | drafts of ideas and documentation
source pypy/goal/ | our main PyPy-translation scripts live here
source pypy/interpreter/ | bytecode interpreter and related objects (frames, functions, modules,...)
source pypy/interpreter/pyparser/ | interpreter-level Python source parser
source pypy/interpreter/astcompiler/ | interpreter-level bytecode compiler, via an AST representation
source pypy/module/ | contains mixed modules implementing core modules with both application and interpreter level code. Not all are finished and working. Use the `--withmod-xxx` or `--allworkingmodules` translation options.
source pypy/objspace/ | object space implementations
source pypy/objspace/std/ | the StdObjSpace implementing CPython's objects and types
source pypy/tool/ | various utilities and hacks used from various places
source pypy/tool/pytest/ | support code for our testing methods
source lib-python/ | our patched fork of the CPython standard library
source lib_pypy/ | contains pure Python implementation of modules that CPython implements in C
source extra_tests/ | extra application-level tests that are usually run after translation
`*/test/` | many directories have a test subdirectory containing test modules (see Testing in PyPy)
`_cache/` | holds cache files from various purposes