@User: The resistor/capacitor corners are "ll", "lh", "hl", and "hh" and are independent of the process corners "ss", "sf", "fs", and "ff". If you use the "sky130.lib.spice" file I made for ngspice, then you can specify, e.g., ".lib sky130.lib.spice hh" for the high-resistance, high-capacitance BEOL corner.