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 on X (formerly Twitter) 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

Project/Tooling Updates

Observations/Thoughts

Rust Walkthroughs

Miscellaneous

Crate of the Week

This week's crate is httpmock, which is quite unsurprisingly a HTTP mocking library for Rust.

Thanks to Jacob Pratt 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. The following RFCs would benefit from user testing before moving forward:

RFCs

  • No calls for testing were issued this week.

Rust

  • No calls for testing were issued this week.

Rustup

  • No calls for testing were issued this week.

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 X (formerly Twitter) 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 X (formerly Twitter) or Mastodon!

Updates from the Rust Project

498 pull requests were merged in the last week

Rust Compiler Performance Triage

This week's results were dominated by the update to LLVM 20 (#135763), which brought a large number of performance improvements, as usually. There were also two other significant improvements, caused by improving the representation of const values (#136593) and doing less work when formatting in rustdoc (#136828).

Triage done by @kobzol.

Revision range: c03c38d5..ce36a966

Summary:

(instructions:u) mean range count
Regressions ❌
(primary)		 4.4% [0.2%, 35.8%] 10
Regressions ❌
(secondary)		 1.2% [0.2%, 5.0%] 13
Improvements ✅
(primary)		 -1.6% [-10.5%, -0.2%] 256
Improvements ✅
(secondary)		 -1.0% [-4.7%, -0.2%] 163
All ❌✅ (primary) -1.3% [-10.5%, 35.8%] 266

3 Regressions, 2 Improvements, 4 Mixed; 4 of them in rollups 50 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.

RFCs

  • No RFCs entered Final Comment Period this week.

Tracking Issues & PRs

Rust
Cargo
  • No Cargo Tracking Issues or PRs entered Final Comment Period this week.
Language Team
  • No Language Team Proposals entered Final Comment Period this week.
Language Reference
  • No Language Reference RFCs entered Final Comment Period this week.
Unsafe Code Guidelines
  • No Unsafe Code Guideline Tracking Issues or PRs entered Final Comment Period this week.

New and Updated RFCs

Upcoming Events

Rusty Events between 2025-02-19 - 2025-03-19 🦀

Virtual

Asia

Europe

North America

Oceania

South America:

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

I have found that many automated code review tools, including LLMs, catch 10 out of 3 bugs.

– Josh Triplett on r/rust

Despite a lamentable lack of suggestions, llogiq is properly pleased with his choice.

Please submit quotes and vote for next week!

This Week in Rust is edited by: nellshamrell, llogiq, cdmistman, ericseppanen, extrawurst, U007D, joelmarcey, mariannegoldin, bennyvasquez, bdillo

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