> It's not true that pcb has a "fundamental" limit of 8 layers.
It uses bitmasks in a 32-bit word for flags, with two bits per layer plus 15 other flags, leaving only one free bit - not enough for another layer. It's a minor technical thing, but it's kinda ingrained in everything else. And IMHO, to generalize the other types of layers, we'd need flags for them too - not the same types of flags, but in general, we need to design for an arbitrary number of flags for each layer, and stop treating copper layers differently than non-copper layers (aside from the "is_copper" flag ;). At the moment we have special cases all over the place to handle the extra two layers.
