The first prototype is done!
You can try it out using this link.
Open the links at the top in new windows or tabs to create “simulations” of micro controllers. There’s one for an LED and one for a button. You will then be able to see all connections on the main page. If you click the listed connections here you will see their details. To connect an LED to a button-sim, just click the button next to the one you want to connect to. When you click the button-sim any connected LEDs will turn on.
Caveat: I haven’t done a lot of debugging, and if there is an error it will crash the server. So if it is not responsive this is probably why.
The next step is to make it pretty, quicker and bug free!