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+.. figure:: https://github.com/pybind/pybind11/raw/master/docs/pybind11-logo.png
+   :alt: pybind11 logo
+
+**pybind11 — Seamless operability between C++11 and Python**
+
+|Latest Documentation Status| |Stable Documentation Status| |Gitter chat| |CI| |Build status|
+
+.. warning::
+
+   Combining older versions of pybind11 (< 2.6.0) with the brand-new Python
+   3.9.0 will trigger undefined behavior that typically manifests as crashes
+   during interpreter shutdown (but could also destroy your data. **You have been
+   warned.**)
+
+   We recommend that you wait for Python 3.9.1 slated for release in December,
+   which will include a `fix <https://github.com/python/cpython/pull/22670>`_
+   that resolves this problem.  In the meantime, please update to the latest
+   version of pybind11 (2.6.0 or newer), which includes a temporary workaround
+   specifically when Python 3.9.0 is detected at runtime.
+
+**pybind11** is a lightweight header-only library that exposes C++ types
+in Python and vice versa, mainly to create Python bindings of existing
+C++ code. Its goals and syntax are similar to the excellent
+`Boost.Python <http://www.boost.org/doc/libs/1_58_0/libs/python/doc/>`_
+library by David Abrahams: to minimize boilerplate code in traditional
+extension modules by inferring type information using compile-time
+introspection.
+
+The main issue with Boost.Python—and the reason for creating such a
+similar project—is Boost. Boost is an enormously large and complex suite
+of utility libraries that works with almost every C++ compiler in
+existence. This compatibility has its cost: arcane template tricks and
+workarounds are necessary to support the oldest and buggiest of compiler
+specimens. Now that C++11-compatible compilers are widely available,
+this heavy machinery has become an excessively large and unnecessary
+dependency.
+
+Think of this library as a tiny self-contained version of Boost.Python
+with everything stripped away that isn’t relevant for binding
+generation. Without comments, the core header files only require ~4K
+lines of code and depend on Python (2.7 or 3.5+, or PyPy) and the C++
+standard library. This compact implementation was possible thanks to
+some of the new C++11 language features (specifically: tuples, lambda
+functions and variadic templates). Since its creation, this library has
+grown beyond Boost.Python in many ways, leading to dramatically simpler
+binding code in many common situations.
+
+Tutorial and reference documentation is provided at
+`pybind11.readthedocs.io <https://pybind11.readthedocs.io/en/latest>`_.
+A PDF version of the manual is available
+`here <https://pybind11.readthedocs.io/_/downloads/en/latest/pdf/>`_.
+And the source code is always available at
+`github.com/pybind/pybind11 <https://github.com/pybind/pybind11>`_.
+
+
+Core features
+-------------
+
+
+pybind11 can map the following core C++ features to Python:
+
+- Functions accepting and returning custom data structures per value,
+  reference, or pointer
+- Instance methods and static methods
+- Overloaded functions
+- Instance attributes and static attributes
+- Arbitrary exception types
+- Enumerations
+- Callbacks
+- Iterators and ranges
+- Custom operators
+- Single and multiple inheritance
+- STL data structures
+- Smart pointers with reference counting like ``std::shared_ptr``
+- Internal references with correct reference counting
+- C++ classes with virtual (and pure virtual) methods can be extended
+  in Python
+
+Goodies
+-------
+
+In addition to the core functionality, pybind11 provides some extra
+goodies:
+
+- Python 2.7, 3.5+, and PyPy/PyPy3 7.3 are supported with an
+  implementation-agnostic interface.
+
+- It is possible to bind C++11 lambda functions with captured
+  variables. The lambda capture data is stored inside the resulting
+  Python function object.
+
+- pybind11 uses C++11 move constructors and move assignment operators
+  whenever possible to efficiently transfer custom data types.
+
+- It’s easy to expose the internal storage of custom data types through
+  Pythons’ buffer protocols. This is handy e.g. for fast conversion
+  between C++ matrix classes like Eigen and NumPy without expensive
+  copy operations.
+
+- pybind11 can automatically vectorize functions so that they are
+  transparently applied to all entries of one or more NumPy array
+  arguments.
+
+- Python’s slice-based access and assignment operations can be
+  supported with just a few lines of code.
+
+- Everything is contained in just a few header files; there is no need
+  to link against any additional libraries.
+
+- Binaries are generally smaller by a factor of at least 2 compared to
+  equivalent bindings generated by Boost.Python. A recent pybind11
+  conversion of PyRosetta, an enormous Boost.Python binding project,
+  `reported <http://graylab.jhu.edu/RosettaCon2016/PyRosetta-4.pdf>`_
+  a binary size reduction of **5.4x** and compile time reduction by
+  **5.8x**.
+
+- Function signatures are precomputed at compile time (using
+  ``constexpr``), leading to smaller binaries.
+
+- With little extra effort, C++ types can be pickled and unpickled
+  similar to regular Python objects.
+
+Supported compilers
+-------------------
+
+1. Clang/LLVM 3.3 or newer (for Apple Xcode’s clang, this is 5.0.0 or
+   newer)
+2. GCC 4.8 or newer
+3. Microsoft Visual Studio 2015 Update 3 or newer
+4. Intel C++ compiler 18 or newer
+   (`possible issue <https://github.com/pybind/pybind11/pull/2573>`_ on 20.2)
+5. Cygwin/GCC (tested on 2.5.1)
+6. NVCC (CUDA 11.0 tested)
+7. NVIDIA PGI (20.7 and 20.9 tested)
+
+About
+-----
+
+This project was created by `Wenzel
+Jakob <http://rgl.epfl.ch/people/wjakob>`_. Significant features and/or
+improvements to the code were contributed by Jonas Adler, Lori A. Burns,
+Sylvain Corlay, Eric Cousineau, Ralf Grosse-Kunstleve, Trent Houliston, Axel
+Huebl, @hulucc, Yannick Jadoul, Sergey Lyskov Johan Mabille, Tomasz Miąsko,
+Dean Moldovan, Ben Pritchard, Jason Rhinelander, Boris Schäling,  Pim
+Schellart, Henry Schreiner, Ivan Smirnov, Boris Staletic, and Patrick Stewart.
+
+We thank Google for a generous financial contribution to the continuous
+integration infrastructure used by this project.
+
+
+Contributing
+~~~~~~~~~~~~
+
+See the `contributing
+guide <https://github.com/pybind/pybind11/blob/master/.github/CONTRIBUTING.md>`_
+for information on building and contributing to pybind11.
+
+License
+~~~~~~~
+
+pybind11 is provided under a BSD-style license that can be found in the
+`LICENSE <https://github.com/pybind/pybind11/blob/master/LICENSE>`_
+file. By using, distributing, or contributing to this project, you agree
+to the terms and conditions of this license.
+
+.. |Latest Documentation Status| image:: https://readthedocs.org/projects/pybind11/badge?version=latest
+   :target: http://pybind11.readthedocs.org/en/latest
+.. |Stable Documentation Status| image:: https://img.shields.io/badge/docs-stable-blue
+   :target: http://pybind11.readthedocs.org/en/stable
+.. |Gitter chat| image:: https://img.shields.io/gitter/room/gitterHQ/gitter.svg
+   :target: https://gitter.im/pybind/Lobby
+.. |CI| image:: https://github.com/pybind/pybind11/workflows/CI/badge.svg
+   :target: https://github.com/pybind/pybind11/actions
+.. |Build status| image:: https://ci.appveyor.com/api/projects/status/riaj54pn4h08xy40?svg=true
+   :target: https://ci.appveyor.com/project/wjakob/pybind11