Congratulations to the team and hope ML family languages become popular and mainstream.

Rust compiler front-end was initially written in OCaml and later moved to rust and dependent on LLVM written in C++. Still Rust became more popular by following a simple imperative style of programming with some incremental improvements over C/C++.

OCaml is confined mostly within Facebook with some use by Bloomberg and in Xen development. I hope functional programming languages become popular and also used for systems programming. OCaml indeed is used for system programming, like Mirage unikernel OS is written in it.

Although OCaml can offer whatever is offered by Rust I believe Rust being imperative language along the lines of C++ will be more popular.

My absolute favorite OCaml program is Unison [1], which is a cross-platform performant file watcher and sync tool.

It's essential to a good VM or remote development experience, and the the principal technology behind docker-sync. (Mac users will thank me.)

[1] https://github.com/bcpierce00/unison

[2] http://docker-sync.io/