Choosing performance as your #1 priority is often a bad idea as it gets you into a straight-jacket from the start, making everything else much more difficult and slows down development to a crawl. Unless you're developing an OS kernel perhaps. Computers are fast enough these days, let them do part of the work for you! And you can always write a faster version of your software when there is a demand for it.
You can write inefficient code and optimize it later.
> it gets you into a straight-jacket from the start, making everything else much more difficult and slows down development time to a crawl. Unless you're developing an OS kernel perhaps
The argument seems to break down: Surely you don't want to be in a strait-jacket if you're developing an OS kernel. Somehow Rust is equated with always being in a strait jacket.
The cost of writing highly concurrent programs is pretty much the same in every language except ones that have concurrency at the core (Erlang). I don't see much difference between starting with Java or Rust in terms of avoiding complexity caused by having to build things that a concurrent runtime could give to you for free.
If you're developing an OS, there is no escaping from the straight-jacket. Your design freedom is severely limited by the fact that your constraints include all applications that will run on your OS.