How to install Lean and mathlib on MacOS #

This document explains how to get started with Lean and mathlib if you are using MacOS.

If you get stuck, please come to the chat room to ask for assistance.

There is a video walkthrough of these instructions on YouTube.

Installing Lean and mathlib #

Here we will discuss the fast way, assuming a lot of trust from you. It will install Lean, with supporting tools elan and leanpkg, the supporting tool leanproject for Lean's mathematical library, as well as the code editor VS Code and its Lean plugin, and other dependencies you probably already have, like curl, git, python3, and pipx. If you don't like this method, there is a detailed webpage which will decompose the process into described stages, and won't ask for a blind sudo.

The fast way is: open a terminal and type:

/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/leanprover-community/mathlib-tools/master/scripts/install_macos.sh)" && source ~/.profile

Lean Projects #

You can now read instructions about creating and working on Lean projects

If you encounter any command not found errors when opening a new terminal, logging out from MacOS and logging in again should fix it.