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.

This Week in Rust is openly developed on GitHub and archives can be viewed at this-week-in-rust.org. If you find any errors in this week's issue, please submit a PR.

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Updates from Rust Community

Official

Newsletters

Project/Tooling Updates

Observations/Thoughts

Rust Walkthroughs

Miscellaneous

Crate of the Week

This week's crate is cargo cat, a cargo-subcommand to put a random ascii cat face on your terminal.

Thanks to Alejandra Gonzáles for the self-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.

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. * Rustikon 2026 | CFP closes: 2025-11-24 23:59 | Warsaw, Poland | Event: 2025-03-19–2025-03-20 Event website

  • TokioConf 2026| CFP closes 2025-12-08 | Portland, Oregon, USA | 2026-04-20
  • RustWeek 2026| CFP closes 2025-12-31 | Utrecht, The Netherlands | 2026-05-19 - 2026-05-20

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

427 pull requests were merged in the last week

Compiler

Library

Cargo

Rustdoc

Clippy

Rust-Analyzer

Rust Compiler Performance Triage

Positive week, most notably because of the new format_args!() and fmt::Arguments implementation from #148789. Another notable improvement came from moving some computations from one compiler stage to another to save memory and unnecessary tree traversals in #148706

Triage done by @panstromek. Revision range: 055d0d6a..6159a440

Summary:

(instructions:u) mean range count
Regressions ❌
(primary)		 1.6% [0.2%, 5.6%] 11
Regressions ❌
(secondary)		 0.3% [0.1%, 1.1%] 26
Improvements ✅
(primary)		 -0.8% [-4.5%, -0.1%] 161
Improvements ✅
(secondary)		 -1.4% [-38.1%, -0.1%] 168
All ❌✅ (primary) -0.6% [-4.5%, 5.6%] 172

2 Regressions, 4 Improvements, 10 Mixed; 4 of them in rollups 48 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:

  • No RFCs were approved 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
Compiler Team (MCPs only)

No Items entered Final Comment Period this week for Cargo, Rust RFCs, Language Team, Language Reference, Leadership Council 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 2025-11-19 - 2025-12-17 🦀

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

We adopted Rust for its security and are seeing a 1000x reduction in memory safety vulnerability density compared to Android’s C and C++ code. But the biggest surprise was Rust's impact on software delivery. With Rust changes having a 4x lower rollback rate and spending 25% less time in code review, the safer path is now also the faster one.

– Jeff Vander Stoep on the Google Android blog

Thanks to binarycat for the suggestion!

Please submit quotes and vote for next week!

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