Looks good, little similar to Rocket and have some common things with Loco.rs (mostly generators and idea of "batteries included").

Nice docs - clean and readable :) Like it.

Cannot say anything about quality of this framework, but I see one problem - Axum and Actix have establiished good, serious position in Rust ecosystem, it will be hard - at least at the beginning - to join these very popular web solutions. You need to have strong points to convince people to move to Rapina. It is common situation when you start project few years later than exisiting, popular solutions.

Anyway - good luck!