Installation

Before you install the LEAN CLI, check if it's already installed.

$ lean --version

If the LEAN CLI is already installed, upgrade it instead of installing it again.

Follow these steps to install the LEAN CLI:

1. Install pip.
2. Install Docker.
3. If you are on a Windows machine, open PowerShell as the adminstrator for the following commands.
4. Install the LEAN CLI with pip.

   $ pip install lean

   This commands downloads all the CLI's dependencies and makes the lean command available in the terminal.
5. If you use Linux, you may need to install tkinter

   $ sudo apt-get install python3-tk

6. Verify the installation was successful.

   $ lean --version

We regularly update the CLI to add new features and to fix issues. Therefore, it's important to keep both the CLI and the Docker images that the CLI uses up-to-date.

Keep the CLI Up-To-Date

To update the CLI to the latest version, run pip install --upgrade lean. The CLI automatically performs a version check once a day and warns you in case you are running an outdated version.

Keep the Docker Images Up-To-Date

Various commands like lean backtest, lean optimize and lean research run the LEAN engine in a Docker container to ensure all the required dependencies are available. When you run these commands for the first time the Docker image containing LEAN and its dependencies is downloaded and stored. Run these commands with the --update flag to update the images they use. Additionally, these commands automatically perform a version check once a week and update the image they use when you are using an outdated Docker image.

To uninstall the Lean CLI, run pip uninstall lean. To perform a full uninstallation, you must also delete configuration files that the CLI generates, which you can find in the following directories:

• The .lean directory in your user's home directory.
• Your workspaces.