This is a cute looking and nice sounding programming game, similar to Zachtronics games like TIS-100 or SHENZHEN I/O. It avoids text-based programming entirely and sticks to numbers flowing through a graph.
I made a sign function (outputs -1 or +1, based on sign of input), but this is way more tricky than you would expect, since you can't generate numbers, and you can only add or subtract 1. I solved it using loops.
Screenshots marked with 🍒 are created by syltefar and are considered public domain, free to use for anything. If you want to, you can note where you found it and link to this page.