Comment by architectonic

I had worked on such a tool by extending pyqtgraph's flowcharts. Mainly executing the nodes when their input changes and showing a glowing box around the one running at the moment. Flowcharts supports multiple terminals already and I had added some custom nodes. Node execution must be delegated to a background thread so the gui is not blocked while the node executes. Doubleclicking a node shows a window for setting up the node. A custom class of nodes shows upon doubleclicking a simple python editor, upon execution the terminals get automatically the values of the variables carrying the same name as the terminals. It has been a lot of fun. I had used petl and pyspark for lazy loading so one could build large etl workflows.