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 kajiya, an experimental real-time global illumination renderer made with Rust and Vulkan.

llogiq is pretty pleased with himself for this 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

340 pull requests were merged in the last week

Rust Compiler Performance Triage

Unfortunately a change introduced in rust-lang/rust#89836 has made performance across different compiler artifacts much more variable by embedding compiler version information (including a git commit hash) in demangled symbol names. This means that even if two compiler artifacts are built from the same exact source code (with only the git commit changed), the compiler will have slightly different performance characteristics. This makes comparisons across pull requests virtually impossible.

The compiler team is still deciding what to do to handle this, but in the mean time, performance testing is largely broken. This issue is currently being tracked inrust-lang/rustc-perf#1126.

Triage done by @rylev. Revision range: 404c847..3d57c61

2 Regressions, 2 Improvements, 23 Mixed; 9 of them in rollups 38 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.


  • No new RFCs entered Final Comment Period this week.

Tracking Issues & PRs

New RFCs

  • No new RFCs were published this week.

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Rust Jobs





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Quote of the Week

Important crab-related diagnostics improvement shipping in nightly @rustlang

error: Ferris cannot be used as an identifier --> src/main.rs:2:9 | 2 | let 🦀 = 123; | ^^ help: try using their name instead: `ferris` 3 | 4 | for i in 0..🦀 { |

Mara Bos on twitter

Thanks to Julian Wollersberger 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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