A rebar plugin
$ rebar3 compile
Add the plugin to your global rebar config ~/.config/rebar3/rebar.conf:
{plugins, [rebar3_live]}.
Then just call your plugin directly in an existing application:
$ rebar3 live
===> Fetching rebar3_live
===> Compiling rebar3_live
<Plugin Output>
Better to install globally. Plugin crashes when installed locally and project fails to compile.