REFAL Studio is an IDE and interpreter for the REFAL programming language. It is written in C++ using Qt QML for the user interface.
REFAL Studio uses a Jupyter-style notebook interface to allow easy interactive programming:
It’s currently still under development, but binary downloads will be available when it’s stable. The source code is available on Github. I also wrote a blog post about the interpreter and the language’s history while I was writing it, which you can find here. I have some bare-bones documentation in progress on the wiki.