@User I'm using Xyce 7.4 with the sky130 libraries. They seem to be syntactically correct and work fine with ngspice. When I run a simple inverter with Xyce, it doesn't function though. The only warnings are:

Netlist warning in file
/software/PDKs/sky130A/libs.tech/ngspice/corners/../../../libs.ref/sky130_fd_pr/spice/sky130_fd_pr__nfet_01v8__tt.pm3.spice
 at or near line 31
 Device instance XBUF_INV2:XPINV_NMOS:MSKY130_FD_PR__NFET_01V8: Source
 conductance reset to 1.0e3 mho

which previously didn't seem to impact my results. I've included a stand-alone example including the libraries.