How to create a Conda environment that uses PyPy?

Question

So here is my issue. I\'ve managed to install PyPy using conda with the following command:

conda install -c conda-forge pypy3.5

Unfortunately,

Answer 1

Worked for me like this:

conda create -n pypy3 -c conda-forge pypy3.5

Afterwards you have to link to the pypy3 interpreter within the bin directory of the env

ln -s pypy3 python

Answer 2

I'm not sure what changed, but conda install pypy3 definitely doesn't work for me (Jan-2021):

conda install pypy3
Collecting package metadata (current_repodata.json): done
Solving environment: failed with initial frozen solve. Retrying with flexible solve.
Collecting package metadata (repodata.json): done
Solving environment: failed with initial frozen solve. Retrying with flexible solve.

PackagesNotFoundError: The following packages are not available from current channels:

  - pypy3

Current channels:

  - https://repo.anaconda.com/pkgs/main/win-64
  - https://repo.anaconda.com/pkgs/main/noarch
  - https://repo.anaconda.com/pkgs/r/win-64
  - https://repo.anaconda.com/pkgs/r/noarch
  - https://repo.anaconda.com/pkgs/msys2/win-64
  - https://repo.anaconda.com/pkgs/msys2/noarch

To search for alternate channels that may provide the conda package you're
looking for, navigate to

    https://anaconda.org

and use the search bar at the top of the page.

Answer 3

Might not achieve exactly what you want, but here's what i've done:

Make a new conda env

conda create --name pypy_env
conda activate pypy_env

Install pypy3 using conda

conda install pypy3

Get Pip for pypy3 using the method here Install pip on pypy

Install packages for pypy using

pypy3 -m pip install <name_of_package>

For some packages it's eaiser to use the pre-built pypy wheel files, some you can find here https://www.lfd.uci.edu/~gohlke/pythonlibs/

Answer 4

Conda now supports PyPy more smoothly.

conda config --set channel_priority strict
conda create -c conda-forge -n pypy pypy
conda activate pypy

There's still a lot of work being done to build conda packages for pypy, but there's already a lot of compatibility. For example,

conda install mpmath
conda install numpy

both work now.

Reference: https://conda-forge.org/blog/posts/2020-03-10-pypy

Also note that the official recommendation for using pip with pypy is described here, the key point of which is this:

Best practices with pip is to always call it as <python> -mpip ..., but if you wish to be able to call pip directly from the command line, you must call pypy -mensurepip --default-pip.