NOTE

this documentation is for the current stable version 1.1. If you are already testing the 1.2.0 beta, head straight to the updated documentation

Installing OPAM

This tutorial is a complement to the Quick Install tutorial and provides complements on how to install OPAM directly from sources. This is not the recommended way of installing OPAM.

Installing OPAM from source

Prerequisites:

  • ocaml (at least 3.12.1)
  • curl or wget
  • git (optional, to use the git backend)
  • rsync (optional, to use the rsync backend)

Obtaining OPAM

Download the latest stable version of OPAM here.

If you want to try the development (unstable) version of OPAM, clone the git repository: git clone git://github.com/ocaml/opam.git. Please keep in mind that this version may not work as expected.

Compiling OPAM

To compile opam (binaries will be installed in /usr/local/bin), simply run:

./configure
make

To have OPAM installed in a specific location, please do

./configure --prefix=/the/opam/path
make

This will fetch the necessary archives if they are not already downloaded and then build OPAM. If you just want to get the necessary dependencies without compiling the project, run make clone.

BSD systems

On *BSD systems, you need to use gmake instead of make. Moreover, the default path for installing the manual pages needs to be changed:

./configure --mandir /usr/local/man
gmake

Installing OPAM

To install opam simply run:

sudo make install

OPAM will be installed under $prefix, that is under /usr/local if you did not specify a prefix in the configure phase, or whatever location you specified.

Initializing OPAM

Before using OPAM, you need to initialize its state. Start by doing:

opam init
eval `opam config env`

This will:

  • Create OPAM configuration files in ~/.opam

  • Add the default remote repository at URL http://opam.ocaml.org using opam’s HTTP repository backend.

  • Update your local environment to be able to use OPAM packages and compilers.

It is recommanded that you add eval `opam config env` in the configuration file of your shell (most likely ~/.bashrc or ~/.profile).

To learn more about these two commands, try opam init --help and opam config --help.

Uninstalling OPAM

To uninstall OPAM, simply run:

$ make uninstall

at the root of the sources. Or you can simply remove OPAM binaries, manual pages and state:

$ rm -rf $(opam config var root)
$ rm -f  $(which opam) $(which opam-admin)