Exploring / fooling around with making a REPL for drawware (inspired by @Ivan Reese’s reference to the paper Advanced Game Engine Wizardry for Visual Programming Environments. Surprising revelation: On the same computer, using just a websocket to connect a browser-based GUI to a Python program which interprets the diagram by shelling out results in turn-around that is "fast enough". It looks instantaneous. No further optimization, nor premature optimization, is required. Biggest missing feature at this point: a change to the diagram should cause the Python program to recompile and re-run the diagram and to update the output fields on the GUI. I think that this could be done by having the Python program periodically sample the 'test.drawio' file timestamp. I know that this is possible, but, I haven't worked out the details yet (suggestions welcome). https://open.substack.com/pub/programmingsimplicity/p/beginning-to-work-on-a-repl-for-drawware?r=1egdky&utm_campaign=post&utm_medium=web&showWelcomeOnShare=true