Getting started on Uiua, I tripped over a typo in hello-world/HELP.md. It says you run tests with uiua tests tests.ua, but the command is uiua test.
One stray s added to test leads to a very cryptic error message.
(I originally posted this in the Roc category: yet another example of the dangers of doing anything early in the morning, before my first cup of coffee)