elan

Overview

Elan’s lean and lake commands read a project’s lean-toolchain file and select the specified Lean version, downloading it when needed. This makes project version pinning practical across local work and CI/CD, rather than relying on a manually maintained global choice.

The separate elan command handles manual installation, selection, execution, and removal of Lean versions. The project describes its lineage as a rustup fork adapted for Lean infrastructure, so its remit is language and SDK version management—not a general development environment manager.

Key features

Project-driven and manual toolchains

Automatic switching follows the project’s toolchain file, while manual commands let developers manage Lean versions themselves. That combination serves teams working across projects pinned to different versions as well as users who need to choose a version outside a project. Project pinning, lockfile support, shell integration, and CI/CD usage are supported.

Installation and platform caveats

Installation guidance covers shell setup on Linux and macOS, PowerShell on Windows, and release downloads for supported platforms. NixOS users should install the Nixpkgs version: elan-downloaded toolchains require patching on that system. Lake also needs git to download dependencies, so a Lean installation alone does not cover that prerequisite.

Elan can uninstall itself and revert the shell configuration changes it made during installation. The repository lists Apache-2.0 and MIT licenses.

Pricing

Elan is free: the elan plan costs 0.00 USD per free and includes Lean version management. There is no free trial because the software is already free, and no paid tier or seat-based plan is described. Its free plan gives up nothing to a paid edition; the trade-off is simply that elan manages Lean versions rather than offering broader language coverage.

Platforms

Elan supports Linux, macOS, and Windows. Its published installation paths vary by operating system, with shell installation for Linux and macOS and PowerShell for Windows. NixOS users should follow the Nixpkgs recommendation rather than depend on elan-downloaded toolchains.

Who it's for

Choose elan if Lean is part of your work and you want project configuration to govern the Lean version, with manual toolchain commands available when needed. Its project pinning and CI/CD support make it suitable for keeping development and automated builds aligned. It is not the right choice for someone seeking one manager for several unrelated language runtimes, and NixOS users should use the recommended Nixpkgs package.

Pros and cons

• Project-specific version selection: the toolchain file can select and trigger download of the Lean version a project needs.
• Manual control remains available: elan can install, select, run, and uninstall versions directly.
• Broad desktop OS support: Linux, macOS, and Windows are supported, with installation paths for each.
• NixOS requires a workaround: downloaded toolchains need patching, so the recommended Nixpkgs version is the better route.
• Lake dependency downloads need git: users must have that dependency available for Lake to fetch packages.

Alternatives

For Lean version management, elan is the focused fit. If the goal is another ecosystem or a broader version-management choice, these free alternatives target different scopes: rustup is another free manager for Linux, macOS, and Windows; fnm is free and supports the same three platforms; nvm is a free Node.js version manager, with Linux, macOS, self-hosted, and Windows support; asdf is a free open-source tool version manager for Linux and macOS; goenv and GVM are free Go version managers for Linux and macOS; PHPBrew is a free PHP version manager for Linux, macOS, and self-hosted setups, though building PHP requires development packages and unsupported older versions may fail; and RVM is another free option with Linux, macOS, self-hosted, web, and Windows platform support.

Browse Runtime Version Managers or Development Environment Managers for more options.

Verdict

Lean developers who want project-pinned toolchains and direct version control should choose elan: it automates the routine version switch without removing manual management. Look elsewhere if you need a multi-language manager; on NixOS, use the Nixpkgs version instead of elan-downloaded toolchains.