Have you spoken with the Rust core team about Microsoft's use of actix? They love getting feedback from commercial users, and I believe they are willing to sign NDAs when necessary (there's certainly plenty of commercial users they seem to be unable to tell me about, and I ask often :P ). I'm happy to put you in touch with them if you'd like; see my email in my HN profile (and this invitation goes for anyone else out there using Rust in production capacities, of course!).