I came across this a few months ago and ignored it for similar reasons: the homepage doesn't talk about the fact that nil is a type not a value (which is AWESOME, btw). It wasn't until a coworker encouraged me to dig into the docs that I realised Crystal is actually pretty sweet.

I recommend stating something like "No unexpected nils at runtime" and for those curious, a link for where to read more. Not having nil is basically the most important feature in most new languages I take the time to play with. Now that I know Crystal treats nil responsibly, I'm really keen to start playing with it.