Installing Ray

Ray should work with Python 2 and Python 3. We have tested Ray on Ubuntu 14.04, Ubuntu 16.04, OS X 10.11 and 10.12.

You can install Ray as follows.

pip install ray

Trying the latest version of Ray

Here are links to the latest wheels (which are built off of master). These versions will have newer features but may be subject to more bugs. To install these wheels, run the following command:

pip install -U [link to wheel]
Linux MacOS
Linux Python 3.6 MacOS Python 3.6
Linux Python 3.5 MacOS Python 3.5
Linux Python 3.4 MacOS Python 3.4
Linux Python 2.7 MacOS Python 2.7

Building Ray from source

If you want to use the latest version of Ray, you can build it from source. Below, we have instructions for installing dependencies and building from source for both Linux and MacOS.


To build Ray, first install the following dependencies. We recommend using Anaconda.

For Ubuntu, run the following commands:

sudo apt-get update
sudo apt-get install -y cmake pkg-config build-essential autoconf curl libtool unzip flex bison psmisc python # we install python here because python2 is required to build the webui

# If you are not using Anaconda, you need the following.
sudo apt-get install python-dev  # For Python 2.
sudo apt-get install python3-dev  # For Python 3.

# If you are on Ubuntu 14.04, you need the following.
pip install cmake

pip install cython

For MacOS, run the following commands:

brew update
brew install cmake pkg-config automake autoconf libtool openssl bison wget

pip install cython

If you are using Anaconda, you may also need to run the following.

conda install libgcc

Install Ray

Ray can be built from the repository as follows.

git clone
cd ray/python
pip install -e . --verbose  # Add --user if you see a permission denied error.

Alternatively, Ray can be built from the repository without cloning using pip.

pip install git+

Test if the installation succeeded

To test if the installation was successful, try running some tests. This assumes that you’ve cloned the git repository.

python test/

Cleaning the source tree

The source tree can be cleaned by running

git clean -f -f -x -d

in the ray/ directory.