You can install different versions of the Elixir with help of Kiex, like in Ruby with a RVM and Rbenv.

Download and install Kiex

\curl -sSL https://raw.githubusercontent.com/taylor/kiex/master/install | bash -s

bash

In .bashrc (or .zshrc if you use z shell), add the following

[[ -s "$HOME/.kiex/scripts/kiex" ]] && source "$HOME/.kiex/scripts/kiex"

bash

Install required Elixir

kiex install 1.7 # or another version

bash

And then you can use any version

kiex use 1.7

bash