update error handling

[aaronleopold]

I think using anyhow and/or thiserror might be beneficial, something like this:

#[derive(Debug, Error)]
pub enum Error {
    #[error("Some defined error: {0}")]
    DefinedErrorName(Box<dyn std::error::Error>),
    #[error("There was an unexpected error: {0}")]
    Other(Box<dyn std::error::Error>),
}

I should also remove some of the unsafe/unchecked unwraps in the code