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? Tweet us at @ThisWeekInRust or send us a pull request. Want to get involved? We love contributions.

This Week in Rust is openly developed on GitHub. If you find any errors in this week's issue, please submit a PR.

Updates from Rust Community




Project/Tooling Updates


Rust Walkthroughs


Crate of the Week

This week's crate is efg, a proc macro to allow boolean expression like syntax for #[cfg]s.

Thanks to farnbams for the suggestion!

Please submit your suggestions and votes for next week!

Call for Participation

Always wanted to contribute to open-source projects but didn't 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.

Updates from the Rust Project

315 pull requests were merged in the last week

Rust Compiler Performance Triage

This week's report started with 6 regressions; after eliminating truly obvious noise, we are left with just 2 minor regressions. Of the cases that regressed, I think the only interesting one is keccak (regressed by 1.73% in PR #91549). But don't be too depressed: keccak was also improved up to 23% by PR #85013 (!); thanks to @simulacrum for that PR.

Triage done by @pnkfelix. Revision range: e2116a..404c847

2 Regressions, 5 Improvements, 3 Mixed; 1 of them in rollups 48 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

New RFCs

  • No new RFCs were published this week.

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Quote of the Week

This is safer than you may think, because those who need async tend to know it themselves and don't ask "should I use async" question. In other words, asking itself is a signal that answer is no. MITM proxy case was a rare exception.

Seo Sanghyeon on rust-users

Thanks to Zeroexcuses for the suggestion!

Please submit quotes and vote for next week!

This Week in Rust is edited by: nellshamrell, llogiq, cdmistman, ericseppanen, extrawurst, andrewpollack, U007D, kolharsam, joelmarcey, mariannegoldin.

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