Most likely I/O will take more time than whatever code is running, so in that aspect it would make no difference. Memory overhead is main concern here. Rust doe

Most likely I/O will take more time than whatever code is running, so in that aspect it would make no difference. Memory overhead is main concern here. Rust doesn't use GC, so you'll have full control and there should be not much difference in that aspect. Other languages do, which means more sophisticated runtime, less control and more overhead (or writing ugly code to avoid it). Libcurl written in Go/Ocaml/Haskell would require anyone using it to also include runtime of the language, which is usually rather large.