Slate
Slate is a dynamically-typed and object-oriented programming language with a simple syntax and powerful reflective capabilities. It is primarily used for developing interactive and graphical applications, as well as prototyping and exploring concepts in programming languages.
Hello, world code example:
inform: 'Hello world!'.
Popularity: Less than 1% of developers are using or have used this language.*
*According to StackOverflow's 2023 survey.