Rust: What is the difference between thiserror and anyhow?

thiserror — derive macro for Error. anyhow — dynamic error type.

thiserror:

• Derive Error trait.
• Clean error definitions.
• For libraries.

anyhow:

• Dynamic errors.
• Quick prototyping.
• For applications.

1use thiserror::Error;
2
3#[derive(Error, Debug)]
4enum MyError {
5    #[error("not found")]
6    NotFound,
7    #[error("io error: {0}")]
8    Io(#[from] std::io::Error),
9}

Key: thiserror for library errors, anyhow for application errors.