This is how it's done

This is all hardcoded, but it's all coded in such a way that it's straightforward to generalize into lists of objects. That same generalization will make it possible to extend lines a little bit so the look nicer at edges (look at the emitters of the transistors here). Some may say that resistors should have more than just the one notch. The whole aesthetic here depends on elements being square on the grid. Don't ask me how I'm going to handle inductors.