Whenever I see "... in Rust" because it is such a popular for hobby projects that are prone to being abandoned. Of course, that might happen to any project in any language, but something tells me that if you manage to get a C codebase to a functional and maintainable point, there is already some energy behind the initiative. There are counter-examples (first and foremost Ripgrep), but I have become so prejudiced in this matter that I'm always skeptical until proven otherwise.