Tower Rust

Use these conventions for Rust request/response services built with tower-rs/tower.

Source Baseline

Prefer released docs from docs.rs/tower, crates.io, and the matching GitHub release over examples from old blog posts or older crate snippets.
Current docs.rs baseline checked for this skill: tower 0.5.3.
Current GitHub release baseline checked for this skill: tower 0.5.3.
Tower is protocol-agnostic middleware for request/response systems. It fits HTTP, gRPC, RPC, and queue-style request handling.
Tower is usually the wrong core abstraction for protocols that are entirely stream based and do not naturally expose discrete requests and responses.
tower itself is not no_std; tower-layer and tower-service are no_std.
Tower's documented MSRV is 1.64.0, but downstream frameworks may require newer Rust versions.

Start with only the features you need. Use full for prototypes, examples, and throwaway experiments, then narrow before production.