ntex was formed after a schism in actix-web (https://actix.rs) and Rust safety/unsafety, with ntex allowing more unsafe code for better performance.
ntex is at the top of the TechEmpower benchmarks and beats most other Rust frameworks, although those benchmarks are not apples-to-apples since each uses its own tricks to eek out more performance: https://www.techempower.com/benchmarks/#hw=ph&test=fortune&s...