Demystifying the i-Device NVMe NAND
    > In order to read the NVMe, I therefor developped a PCIe card with a Zero
    > Insertion Force reader. I brought the JTAG part to 20pin header. The hard
    > pard in here is the signal integrity of the differential pairs. In order
    > to do so, I had to use multi layer PCB, and have the impedence match by
    > knowing the stackup, materials used for prepeg and so on..

Posts like this are very humbling.  They serve as a good reminder that no matter how far I've come and how much I've learned, there will always be someone out there who knows vastly more than me like the back of their hand.