Windows Installation

Download the Lean zip file for Windows, and unfold it in a directory of your choice.

Configuring Lean emacs mode

To use the Lean emacs mode, you must have Emacs version 24.3 (or greater) and Python installed on your system. Either Python 2.7 or 3.5 should work.

Both Emacs and Python need to be added to your %PATH%.

  • Use Win+Pause to open System Properties.
  • Under Windows 7 or newer, click on Advanced system settings.
  • Click on Environment Variables….
  • Under System Variables find Path then choose to Edit….

Assuming Emacs and Python 2.7 have been installed at their default locations, append the following to the end of the path (include the first ; only if not already present):


If you installed Python 3.5 and checked the option to add Python to the system path, you only need to add Emacs.

Starting Lean Emacs mode

After Emacs and Python have been added to your %PATH%. You can start the Lean emacs mode by executing the bin\leanemacs.bat.

Advanced users can configure their .emacs initialization file using these instructions.