For me I think “written in Rust”actually does add a lot.
It is a signal that this will be easy to build, easy to deploy (because it is compiled into a single binary in general), memory safe, and likely to be written by a someone that cares about performance and efficiency.
Only "easier to deploy" and "faster in general" are valid points. Most languages used to write servers are practically memory safe, and there are lot of hipsters in rust crowd too.
That's an incorrect assumption if you haven't audited the code.
> likely to be written by a someone that cares about performance and efficiency
Ah, the stamp of approval that comes from signalling to the "right people". Reminds me of the preamble to almost every C++ Boost library -- "written with performance in mind".
I guess Rust isn't guaranteed to be memory safe considering unsafe blocks but it does make it much more memory safe than languages which only offer manual memory management.
I didn't know about that preamble, but I definitely got the vibe of "written on a write-only mindset"... just from reading their docs :) not to say trying to delve in the source code!
Rust hasn't magically solved concurrency safety either, as linearity is not enough.
GC'd languages (Java, Go, Haskell etc) are safer than Rust by default, you just have the tradeoff of GC. Note that this isn't always a tradeoff as GCs can outperform static allocation in scenarios like large dynamic heaps.
Haskell is the safest for concurrency because of the strictly typed functional semantics.
It is a signal that this will be easy to build, easy to deploy (because it is compiled into a single binary in general), memory safe, and likely to be written by a someone that cares about performance and efficiency.
I think those are all valuable hints.