Clone ign-embed to the directory in which an FCOS ISO file resides. make embed adds installation.service an automated installation unit to the FCOS ISO file.
(Also enables login as core/fcos)
# Transpile installer.yaml to installer.json
make
# Embed installer.json to the ISO file in parent directory
make embed
To monitor the installations which occur on first boot:
watch -n 2 sudo systemctl list-jobs