FYI, Travis and friends have done a LOT of open-source posting on their usage of Embedded Haskell and Haskell for electronic warfare. They have some kind of embedded Haskell setup that’s military grade and suitable for hard real time (and they brag about it). See: Anduril Industries is hiring Haskell Developers
As for Linear Haskell, the idea is that you use linear types to remove the need for a garbage collector as it’s explicit when memory needs to be cleaned up, in the same way Rust has GC-like characteristics via affine types but doesn’t actually use a GC.
In theory, it’s supposed to make Haskell suitable for hard real time use, but at least the clearspace version is extremely experimental. I’ve overheard that Linear Haskell doesn’t even outperform the ST type in many cases because of missing compiler optimizations.
As far as Rust goes:
DARPA Turns to AI to Help Turn C and C++ Code Into Rust - DevOps.com(DOD,adopt%20memory-safe%20programming%20languages.
A while back, someone commented to me that the military is very big on experimental languages and computer technology, at least for experiments, i.e, someone claimed that the logistics management of Desert Storm was handled by Prolog, of all things. In fact, remember that we’re all using the semi-civilianized descendant of ARPANET.
To me at least, it sounds like one of those things where we all pretend everything is normal until someone defects to the Russians after the Hong Kong government refuses to extradite them, blaming paperwork errors, and we get a tell-all. Except that there’s already a lot of stuff publicly disclosed by Anduril themselves.