opam command not found

In this troubleshooting guide we learn how to fix opam command not found error message

Introduction

When you run more command in linux terminal / console, you get the following error message

opam: command not found

or when using sudo you get the following error message

sudo: opam: command not found

In Ubuntu opam is provided by opam package.

opam is:

OPAM stands for OCaml PAckage Manager. It aims to suit to a vast number of users and use cases, and has unique features:

Powerful handling of dependencies: versions constraints, optional dependencies, conflicts, etc.
Multiple repositories backends: HTTP, rsync, git
Ease to create packages and repositories
Ability to switch between different compiler versions

Typically, OPAM will probably make your life easier if you recognize yourself in at least one of these profiles:

You use multiple versions of the OCaml compiler, or you hack the compiler yourself and needs to frequently switch between compiler versions.
You use or develop software that needs a specific and/or modified version of the OCaml compiler to be installed.
You use or develop software that depends on a specific version of an OCaml library, or you just want to install a specific version of a package, not just the latest one.
You want to create your own packages yourself, put them on your own repository, with minimal effort.

To fix this problem, we can install more using the command below.

sudo apt-get -y install opam

This command might take some time to finish depending on your machine internet connection.

You can also use apt command to install opam.

sudo apt -y install opam

Or if you have aptitude installed you can use the following command.

sudo aptitude install opam

In this tutorial we learn how to fix opam command not found error in Ubuntu / Debian / Kali Linux or Raspbian distribution.