repl.it : Powerful and simple online compiler, IDE, interpreter, and REPL. Code, compile, and run code in 30+ programming languages. including JavaScript, Pytho...
ideone.com : Ideone is an online compiler and debugging tool which allows youto compile source code and execute it online in more than 60 programming languages.
Black : By using Black, you agree to cede control over minutiae of hand-formatting. In return, Black gives you speed, determinism, and freedom from pycodestyl...
Maqetta : Maqetta is an open source project that provides WYSIWYG visual authoring of HTML5 user interfaces. The Maqetta application itself is authored in HTML,...
Elixir : Elixir is a dynamic, functional language designed for building scalable and maintainable applications.
Elixir leverages the Erlang VM, known for runni...