Highway is a service that manages a Manufacturer Installed Certificate (MICs) subsystem.
Highway is a MASA == Manufacturer Assigned Signing Authority. Please see: https://datatracker.ietf.org/doc/draft-ietf-anima-bootstrapping-keyinfra/ and also: https://datatracker.ietf.org/doc/draft-richardson-anima-masa-considerations/
Highway can also sign https://www.rfc-editor.org/info/rfc8520 Manufacturer Usage Description files.
MICs are created by a vendor to be installed in a device during manufacturer.
Details on setting this up with Docker, LXC and VMs starts at README-DOCKER