SikuliX automates anything you see on the screen of your desktop computer running Windows, Mac or some Linux/Unix. It uses image recognition powered by OpenCV to identify GUI components and can act on them with mouse and keyboard actions. This is handy in cases when there is no easy access to a GUI's internals or the source code of the application or web page you want to act on.
nut.js gives you full control over your mouse. Move, click or drag your cursor where you need it! Press (and hold) single keys or type pages of text, nut.js handles both! It allows for native UI interactions via keyboard and/or mouse but additionally gives you the possibility to navigate the screen based on image matching. nut.js gives you access to your system clipboard. Copy and paste text as you go!