We prefer using asdf to manage versions of Elixir, react and node.js projects.
You can copy and paste this and save it as .tool-versions in the same
directory of your new project.
erlang 22.2
elixir 1.9.4
nodejs 10.15.3
Afterwards, run asdf install to install the versions. Note that the version
numbers found in this markdown file will be constantly updated.