crab@crab:~/dev/todolist$ opam init

<><> Required setup - please read <><><><><><><><><><><><><><><><><><><><><><><>

  In normal operation, opam only alters files within ~/.opam.

  However, to best integrate with your system, some environment variables
  should be set. If you allow it to, this initialisation step will update
  your bash configuration by adding the following line to ~/.profile:

    test -r /home/crab/.opam/opam-init/init.sh && . /home/crab/.opam/opam-init/init.sh > /dev/null 2> /dev/null || true

  Otherwise, every time you want to access your opam installation, you will
  need to run:

    eval $(opam env)

  You can always re-run this setup with 'opam init' later.

Do you want opam to modify ~/.profile? [N/y/f]
(default is 'no', use 'f' to choose a different file) y
A hook can be added to opam's init scripts to ensure that the shell remains in sync with the opam environment when they are loaded. Set that up? [y/N] n

User configuration:
  Updating ~/.profile.
[NOTE] Make sure that ~/.profile is well sourced in your ~/.bashrc.