How to install opam

This page describes how to install and configure opam. For further help on how to use opam, either read opam --help or move on to the Usage guide.

Upgrading from a previous version

Generally, you should just reproduce the same installation steps as for the original installation: upgrade from your system's package manager, or re-run the binary installer. Opam will automatically update its internal repository at ~/.opam on first run if needed (if using our installer script, a backup can be made automatically).

To upgrade shell scripts, and enable sandboxing, don't forget to run opam init --reinit -ni.

Then see the Upgrade guide to check the changes.

Binary distribution

The quickest way to get the latest opam up and working is to run this script:

bash -c "sh <(curl -fsSL https://opam.ocaml.org/install.sh)"

or this script on Windows using PowerShell:

Invoke-Expression "& { $(Invoke-RestMethod https://opam.ocaml.org/install.ps1) }"

This will simply check your architecture, download and install the proper pre-compiled binary, backup your opam data if from an older version, and run opam init.

(If you have trouble with curl, just download the script and run sh install.sh)

We provide pre-compiled binaries for:

  • Linux (amd64, arm64, ppc64le, s390x, riscv64, armhf, i686)
  • macOS (amd64, arm64)
  • FreeBSD (amd64)
  • OpenBSD (amd64)
  • NetBSD (amd64)
  • Windows (amd64) (other platforms are available using the other methods below)

If you don't like scripts, you can just pick your download here, put it in your PATH as opam, and set it as executable, e.g.

sudo install <downloaded file> /usr/local/bin/opam

Note that this script is intended for end-users, not CI. For that purpose, you can use pre-built Docker images for various configurations.

Using your system's package manager

This is generally the recommended way, when available and up-to-date. You can check the following table, and the way to install opam thereafter:

repology package status

Arch Linux

pacman -S opam

Debian and Ubuntu

apt install opam

Fedora

dnf install opam

Mageia

urpmi opam

Alpine Linux

apk add opam

OpenBSD

pkg_add opam

FreeBSD

pkg install ocaml-opam

macOS

Opam packages for Homebrew and MacPorts are available.

# Homebrew
brew install opam

# MacPort
port install opam

Guix & Guix System

guix install opam

Windows

winget install Git.Git OCaml.opam

WinGet the Windows Package Manager is available on Windows 11, modern versions of Windows 10, and Windows Server 2025. See the official documentation for additional info.

From Sources

Getting the Sources

Sources of the latest stable version of opam are available on Github:

You can also download the full archives, including opam dependencies (these don't require any extra downloads):

  • 2.3.0
    • MD5: 81d029c2b79c53f4d99005df47696bef
    • SHA384: 7c62af375f7fc293236f5ce49c51957f39356a937a578683a79fbe1a3ed9e96b64d97c369206923248cbec62c4c251dc

Follow the instructions in the included README.md to get opam built and installed from there.