I do not have aphantasia. Too much phantasia if anything. But I don’t visualize shapes and colors when programming. In fact I find block and arrow diagrams confusing. I visualize the code itself, but zoomed out. It takes on the feel of a house I’ve spent a lot of time in. I know my way around, I know where I left my hat (a function) when I walked in (when I wrote it), which drains clog easily (hairy IO code), which furniture needs dusting (code I haven’t looked at in a while). But to be clear, this is a non-visual metaphor. The visual is the code.