Radar · Rust · Archive · Week 32 · Aug 4 – 10, 2025

mdbook 0.4.52 Update

Worth knowingtooling

What changed: The mdbook dependency was updated to 0.4.52. The update adds the ability to redirect # HTML fragments, adds a rel="edit" attribute to the edit page button, defers loading the search index until the search input is opened, switches mdbook serve’s server library from warp to axum, and includes several dependency updates.
Production impact: The source does not say.
Try it: Run mdbook serve and observe that the search index loads only when you type in the search box.
Source: github.com/rust-lang/rfcs/pull/3843

Understand it, then run it

The update bumps the mdbook library from 0.4.51 to 0.4.52. mdbook is the tool that builds Rust documentation into a static website. With the new version you can now redirect URLs that end with a # fragment, add a rel="edit" attribute to the edit button, and the search page will load its index only when you open the search box. The command that serves the book locally (mdbook serve) now uses a different web framework, but that change is invisible to most users.

Run it now

Todayrust

// This program demonstrates that the `mdbook` crate is not part of the
// standard library and therefore cannot be used directly in a minimal
// Rust 1.98.1 (edition 2024) program. It simply prints a message
// confirming that `mdbook` is an external dependency.

fn main() {
    println!("The `mdbook` crate is an external dependency and not available in the standard library.");
}

What it printed when we ran it on Rust 1.98.1 (edition 2024)

The `mdbook` crate is an external dependency and not available in the standard library.

Run sends this program (for Solidity, the contract and its tests) to our own sandbox, where it is compiled and run once, with no network, and what it printed or the test report comes back here. Nothing is kept. Runs are counted per visitor for the day so everyone gets a turn; the details are on the legal page.

Written by gpt-oss-20b from the linked source · claims checked against the sources · archive, not individually reviewed