Rust] How bad is to use unsafe code internally in a library?

https://www.reddit.com/r/rust/comments/kn4pf5/how_bad_is_to_use_unsafe_code_internally_in_a/?utm_source=share&utm_medium=ios_app&utm_name=iossmf

How bad is to use unsafe code internally in a library?

How bad is to use unsafe code internally in a library?

I'm trying to write a Rust library to interop with an old C library. The final user will have a 100% safe Rust API. However to make this work, I find myself using *a lot* of unsafe blocks internally, "for a greater good".

Also, sometimes storing a raw pointer seems to be the most sane choice, because it alleviates the burden to the final user, and *I know* the pointer will be valid because of the internal implementation.

So, at this point, this is my dilemma:

* keep using unsafe code internally, providing a more ergonomic API to the final user; or
* use less unsafe code internally, and let the user deal with extra syntax.

I know there's **no** definitive answer to this, but I'd really like to read your own guidelines when facing such implementations.