t-rex

https://github.com/isene/t-rex

This is a terminal curses RPN calculator similar to the traditional calculators from Hewlett Packard. See https://www.hpmuseum.org/rpn.htm for info on RPN (Reverse Polish Notation). Version 4.0.0: Breaking change - requires rcurses 6.0.0+ with explicit initialization for Ruby 3.4+ compatibility.