Here's full-mixed-language programmable, locally- and fully-remote-debuggable, mixed-user and inner-mode processing unikernel, and with various other features...
This from 1986...
http://bitsavers.trailing-edge.com/pdf/dec/vax/vaxeln/2.0/VA...
FWIW, here's a unikernel thin client EWS application that can be downloaded into what was then an older system, to make it more useful for then-current X11 applications...
From 1992...
http://h18000.www1.hp.com/info/SP3368/SP3368PF.PDF
Anybody that wants to play and still has a compatible VAX or that wants to try the VCB01/QVSS graphics support in some versions of the (free) SIMH VAX emulator, the VAX EWS code is now available here:
http://www.digiater.nl/openvms/freeware/v50/ews/
To get an OpenVMS system going to host all this, HPE has free OpenVMS hobbyist licenses and download images (VAX, Alpha, Itanium) available via registration at:
https://h41268.www4.hp.com/live/index_e.aspx?qid=24548&desig...
Yes, this stuff was used in production, too.