Look at my companies I work with via Distrust, and my resume. Most use stagex for their security critical operations, though I am unable to say which ones specifically. NDAs and all that. You could figure out a few of them if you looked.
I can tell you many many fortune 500 companies are relying on stagex for security critical use cases, and most are probably not even aware of it as they consume projects that wrap or build on stagex.