Principal Engineer or Lead Engineer. In particular, you want someone with experience in very early-stage startups (where they might have been responsible for some hardware decisions).
The point about the "very early stage" is that it's unlikely for one single person to have all the skills you want unless they had no other choice, i.e. they were the first or second engineer in a startup.
So, to find one person to satisfy your job description, look for someone who was an early engineer at a startup.
Or, hire two people (who will usually cost you less money).
In SV, the recommendation is to hire that one special person, but I'm not so sure. This is particularly true if you live outside a hub (SV, Seattle, etc) and this type of employee becomes even more rare.
"very early-stage": Is it relevant we currently have over 100,000 users and are already profitable?