Main differences to Voila: - Mercury has no callbacks - we automatically re-execute cells below updated widget, - Mercury has no layout widgets, all input wid

Main differences to Voila: - Mercury has no callbacks - we automatically re-execute cells below updated widget, - Mercury has no layout widgets, all input widgets are always in the left sidebar and output content appear in the same order as in notebook. Thanks to above decisions you don't need to rewrite your notebook to fit UI framework paradigms.