[dralley]

By "rust docs" you seem to mean "docs.rs, the website that hosts documentation for all crates in the Rust ecosystem", which is a little bit different than the impression you give.

It's a whole web services with crates.io webhooks to build and update new documentation every time a crates gets updated, tracks state in a database and stores data on S3, etc. Obviously if you just want to build some docs for one crate yourself you don't need any of that. The "rustdoc" command has a much smaller list of dependencies.