Since you asked, here’s `rebar3_flamingo`. A rebar plugin that prints flamingos. 🦩
One thing I did figure out that might be useful in lieu of the guide I planned to write: to test a rebar3 plugin, add it to its own `project_plugins`, then symlink `_checkouts/rebar3_flamingo` back to `..`.
Now you can call `rebar3 flamingo` from its own project root.