Hello and welcome to another issue of This Week in Rust! Rust is a programming language empowering everyone to build reliable and efficient software. This is a weekly summary of its progress and community. Want something mentioned? Tag us at @thisweekinrust.bsky.social on Bluesky or @ThisWeekinRust on mastodon.social, or send us a pull request. Want to get involved? We love contributions.

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Updates from Rust Community

Official

Newsletters

Observations/Thoughts

Rust Walkthroughs

Crate of the Week

This week's crate is iddqd, a library of maps where keys are borrowed from values.

Thanks to Miro for the suggestion!

Please submit your suggestions and votes for next week!

Calls for Testing

An important step for RFC implementation is for people to experiment with the implementation and give feedback, especially before stabilization.

If you are a feature implementer and would like your RFC to appear in this list, add a call-for-testing label to your RFC along with a comment providing testing instructions and/or guidance on which aspect(s) of the feature need testing.

No calls for testing were issued this week by Rust, Cargo, Rustup or Rust language RFCs.

Let us know if you would like your feature to be tracked as a part of this list.

RFCs

Rust

Rustup

If you are a feature implementer and would like your RFC to appear on the above list, add the new call-for-testing label to your RFC along with a comment providing testing instructions and/or guidance on which aspect(s) of the feature need testing.

Call for Participation; projects and speakers

CFP - Projects

Always wanted to contribute to open-source projects but did not know where to start? Every week we highlight some tasks from the Rust community for you to pick and get started!

Some of these tasks may also have mentors available, visit the task page for more information.

If you are a Rust project owner and are looking for contributors, please submit tasks here or through a PR to TWiR or by reaching out on Bluesky or Mastodon!

CFP - Events

Are you a new or experienced speaker looking for a place to share something cool? This section highlights events that are being planned and are accepting submissions to join their event as a speaker.

If you are an event organizer hoping to expand the reach of your event, please submit a link to the website through a PR to TWiR or by reaching out on Bluesky or Mastodon!

Updates from the Rust Project

659 pull requests were merged in the last week

Compiler

Library

Cargo

Rustdoc

Rustfmt

Clippy

Rust-Analyzer

Rust Compiler Performance Triage

A quiet week performance-wise. The only notable change was a major regression in #165335, which might get reverted.

Triage done by @Kobzol. Revision range: 4c46afa6..54d0b7ed

Summary:

(instructions:u) mean range count
Regressions ❌
(primary)		 1.0% [0.2%, 3.7%] 163
Regressions ❌
(secondary)		 1.2% [0.0%, 4.6%] 159
Improvements ✅
(primary)		 -2.2% [-3.9%, -0.3%] 8
Improvements ✅
(secondary)		 -0.7% [-1.6%, -0.2%] 10
All ❌✅ (primary) 0.8% [-3.9%, 3.7%] 171

6 Regressions, 5 Improvements, 3 Mixed; 6 of them in rollups 189 artifact comparisons made in total

Full report here.

Approved RFCs

Changes to Rust follow the Rust RFC (request for comments) process. These are the RFCs that were approved for implementation this week:

Final Comment Period

Every week, the team announces the 'final comment period' for RFCs and key PRs which are reaching a decision. Express your opinions now.

Tracking Issues & PRs

Rust
Rust RFCs
Cargo
Leadership Council

No Items entered Final Comment Period this week for Compiler Team, Language Team, Language Reference or Unsafe Code Guidelines. Let us know if you would like your PRs, Tracking Issues or RFCs to be tracked as a part of this list.

New and Updated RFCs

  • No New or Updated RFCs were created this week.

Upcoming Events

Rusty Events between 2026-11-11 - 2026-12-09 🦀

Virtual

Asia

Europe

North America

Oceania

If you are running a Rust event please add it to the calendar to get it mentioned here. Please remember to add a link to the event too. Email the Rust Community Team for access.

Jobs

Please see the latest Who's Hiring thread on r/rust

Quote of the Week

No, actually it is harder. Much harder. Your brain normally runs an error-correction pass on every word you read before that word reaches your conscious attention. This is why it's so easy to miss typos, but the correction doesn't just hide typos from you, it can replace entire phrases with what "ought" to be there. It takes continuous concentration to suppress this effect.

[…]

(Curly brace placement is of course also subject to the error filter, but curly braces go with large changes in indentation, and that's usually a big enough visual flag to get past the filter. In fact that's why Rust requires all blocks to be braced -- the experience with C was that people would think indented statements were braced when they weren't.)

– Zack Weinberg on rust-internals

Thanks to Michael Howell for the suggestion!

Please submit quotes and vote for next week!

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