Do we know of start-up ventures where the Rust programming language was used to gain a competitive advantage? I was not good at googling and duck-duck-going, therefore I am asking.
Looking at “who’s hiring” threads for Rust can give you some companies. https://www.rust-lang.org/en-US/friends.html is a list of companies, you’d have to figure out if they’re start-ups yourself though.
I don't know myself, but you can check out stackshare.io and similar sites. It looks like some larger startups are using it at least in some limited areas, e.g. dropbox, cloudflare.