How much does the syntax differ from ruby ? Do you think I should learn crystal by porting a smallish ruby CLI app to it, or make one from scratch porting a sm

How much does the syntax differ from ruby ? Do you think I should learn crystal by porting a smallish ruby CLI app to it, or make one from scratch porting a small bash app ? I was thinking of doing it in `go` or `rust` but thinking of crystal after seeing this article.