Crystal (programming language)
Crystal is a high-level general-purpose, object-oriented programming language, designed and developed by Ary Borenszweig, Juan Wajnerman, Brian Cardiff and more than 530 contributors. With syntax inspired by the language Ruby, it is a compiled language with static type-checking, but specifying the types of variables or method arguments is generally unneeded.
Source: Wikipedia — Crystal (programming language) (CC BY-SA 4.0)