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This post is auto-generated from RSS feed This Week in Rust. Source: This Week in Rust 608

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

• crates.io: development update | Rust Blog
• Call for Testing: Speeding up compilation with hint-mostly-unused

Newsletters

• This Month in Rust OSDev: June 2025

Project/Tooling Updates

• egui 0.32 - Atoms, popups, and better SVG support
• reqwest retries
• Introducing Rudy: A Toolchain for Rust Debuginfo
• RootAsRole 3.1.0 - Outperforms sudo, configurability, -u, -g, -E features
• Helix Release 25.07 Highlights
• UltraGraph 0.8: 1,300x Faster Graph Analytics — No Cluster Needed

Observations/Thoughts

• placing functions
• Rust is a great fit for the agentic era
• Here comes the sun: iteratively building a Rust program that gets the current weather conditions
• Thinking in Rust: Ownership, Access, and Memory Safety
• Adding lookbehinds to rust-lang/regex
• Publish all your crates everywhere all at once
• Variadic Generics ideas that won’t work for Rust
• [audio] Traceability
• KSAT with Vegard Sandengen

Rust Walkthroughs

• Programming Extensible Data Types in Rust with CGP - Part 3: Implementing Extensible Records
• Axum: Optimizing web API design with the Builder Pattern
• Rust unit testing test types

Research

• Tree Borrows
• Securing Mixed Rust with Hardware Capabilities

Miscellaneous

• June 2025 Rust Jobs Report

Crate of the Week

This week's crate is oxvg, a SVG optimizer.

Thanks to Noah Baldwin 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.

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

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

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.

• Diesel: Designing #[derive(QueryModel)] Poll I - Default for #[diesel(check_for_backend()]
• Diesel: Designing #[derive(QueryModel)] Poll II - Joining behaviour for #[diesel(embed)]
• Diesel: Designing #[derive(QueryModel)] Poll III - All in one derive?

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.

No Calls for papers or presentations were submitted this week.

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

421 pull requests were merged in the last week

Compiler

• use lld by default on x86_64-unknown-linux-gnu stable
• apply effects to otherwise edge in dataflow analysis
• compute all rpitit of a trait
• consider nested cases for duplicate RPITIT
• propagate from borrowed locals in CopyProp
• resolver: refactor macro map into external and local maps

Library

• constify Fn* traits
• constify From and Into
• make Default const and add some const Default impls
• slice: mark rotate_left, rotate_right unstably const
• core: add BorrowedCursor::with_unfilled_buf
• implement int_format_into feature

Cargo

• add [hints] table in Cargo.toml, and a hints.mostly-unused hint
• implementation and tests for multiple-build-scripts
• perf: speed up TOML parsing by upgrading toml

Rustdoc

• don't mark #[target_feature] safe fns as unsafe in rustdoc JSON

Clippy

• arithmetic_side_effects: don't warn on NonZeroU*.get() - 1
• or_fun_call: lint method calls inside map_or first arg
• {flat_,}map_identity: recognize |[x, y]| [x, y] as an identity function as well
• add uninlined_format_args example for {:?}
• do not remove method call if type is adjusted
• fix approx_const for some new cases
• fix expect_fun_call producing invalid suggestions
• fix legacy_numeric_constants suggestion when call is wrapped in parens
• fix manual_abs_diff suggests wrongly behind refs
• fix manual_assert suggests wrongly for macros
• fix manual_is_variant_and condition generation
• fix false negative of expect_used
• fix manual is multiple of
• fix multiple problems in #15063
• fix suggestion causes error of needless_for_each
• skip exit late lint pass on tests

Rust-Analyzer

• rust-analyzer: generate new for tuple struct
• rust-analyzer: support folding multiline arg list & fn body in one folding range
• rust-analyzer: assoc type where clause position
• rust-analyzer: fix display of use<> syntax
• rust-analyzer: fixes for dyn inlay hint
• rust-analyzer: inline asm fixes
• rust-analyzer: normalize projection types before calculating memory maps
• rust-analyzer: perf: put the expression stuff in the expression store behind an Option<Box>

Rust Compiler Performance Triage

A busy week with a lot of rollups containing perf. regressions and mixed results. Overall, regressions won slightly, but there were also a few impressive wins on a few primary and secondary benchmarks. A lot of perf. effects are caused by the current rework of attribute parsing, which will hopefully result in slightly improved performance once it's finished.

Triage done by @kobzol. Revision range: 0d11be5a..a9fb6103

Summary:

(instructions:u)	mean	range	count
Regressions ❌ (primary)	0.5%	[0.1%, 1.5%]	62
Regressions ❌ (secondary)	0.5%	[0.1%, 1.8%]	78
Improvements ✅ (primary)	-0.4%	[-3.9%, -0.1%]	40
Improvements ✅ (secondary)	-1.4%	[-11.6%, -0.0%]	74
All ❌✅ (primary)	0.1%	[-3.9%, 1.5%]	102

5 Regressions, 4 Improvements, 8 Mixed; 5 of them in rollups 47 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

• Guarantee 8 bytes of alignment in Thread::into_raw
• rustdoc: add ways of collapsing all impl blocks
• Stabilize const_float_round_methods
• Tracking Issue for #![feature(const_float_round_methods)]
• Add target_env = "macabi" and target_env = "sim"

Rust RFCs,

• Closing issues relevant to T-lang on this repo

No Items entered Final Comment Period this week for Cargo, 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

• [new] repr(scalable)

Upcoming Events

Rusty Events between 2025-07-16 - 2025-08-13 🦀

Virtual

• 2025-07-16 | Hybrid (Vancouver, BC, CA) | Vancouver Rust
  • Rust Study/Hack/Hang-out
• 2025-07-17 | Hybrid (Redmond, WA, US) | Seattle Rust User Group
  • July, 2025 Computer Programming Language Panel (Special Event)
• 2025-07-17 | Virtual (Berlin, DE) | Rust Berlin
  • Rust Hack and Learn
• 2025-07-20 | Virtual (Dallas, TX, US) | Dallas Rust User Meetup
  • Rust Readers Discord Discussion: Rust Atomics and Locks
• 2025-07-22 | Virtual (Dallas, TX, US) | Dallas Rust User Meetup
  • Fourth Tuesday
• 2025-07-22 | Virtual (London, UK) | Women in Rust
  • Lunch & Learn: Crates, Tips & Tricks Lightning Talks - Bring your ideas!
• 2025-07-24 | Virtual (Nürnberg, DE) | Rust Nuremberg
  • Rust Nürnberg online
• 2025-07-27 | Virtual (Dallas, TX, US) | Dallas Rust User Meetup
  • Rust Readers Discord Discussion: Rust Atomics and Locks
• 2025-07-31 | Virtual (Berlin, DE) | Rust Berlin
  • Rust Hack and Learn
• 2025-08-02 | Virtual (Kampala, UG) | Rust Circle Meetup
  • Rust Circle Meetup
• 2025-08-03 | Virtual (Dallas, TX, US) | Dallas Rust User Meetup
  • Rust Readers Discord Discussion: Rust Atomics and Locks
• 2025-08-06 | Virtual (Indianapolis, IN, US) | Indy Rust
  • Indy.rs - with Social Distancing
• 2025-08-10 | Virtual (Dallas, TX, US) | Dallas Rust User Meetup
  • Rust Readers Discord Discussion: Rust Atomics and Locks
• 2025-08-12 | Virtual (Dallas, TX, US) | Dallas Rust User Meetup
  • Second Tuesday

Asia

• 2025-07-19 | Delhi, IN | Rust Delhi
  • Rust Delhi Meetup #11
• 2025-07-26 | Bangalore, IN | Rust Bangalore
  • July 2025 Rustacean meetup

Europe

• 2025-07-23 | Dortmund, DE | Rust Dortmund
  • Rust Dortmund Meetup - Teach and Hack
• 2025-07-24 | Edinburgh, UK | Rust and Friends
  • July talks: A Crab, a Pufferfish and a State-of-the-art Chess AI
• 2025-07-24 | Nuremberg/Nürnberg, DE | Rust Nuremberg
  • Rust Nürnberg online
• 2025-07-26 | Stockholm, SE | Stockholm Rust
  • Ferris' Fika Forum #15
• 2025-07-29 | Manchester, UK | Rust Manchester
  • Lightning Talks July 2025
• 2025-07-29 | Prague, CZ | Rust Czech Republic
  • Nix Meetup at Braiins :)
• 2025-07-30 | Amsterdam, NL | Rust Developers Amsterdam Group
  • Rust Meetup @ BlockTech
• 2025-07-31 | Augsburg, DE | Rust Meetup Augsburg
  • Rust Meetup #14: Prof. Dr. Claudia Meitinger - Embassy - Möglichkeiten und Herausforderungen im Modul "Interdisciplinary Project"
• 2025-08-06 | Girona, ES | Rust Girona
  • Rust Girona Hack & Learn 08 2025
• 2025-08-13 | Reading, UK | Reading Rust Workshop
  • Reading Rust Meetup

North America

• 2025-07-16 | Hybrid (Vancouver, BC, CA) | Vancouver Rust
  • Rust Study/Hack/Hang-out
• 2025-07-17 | Chicago, IL, US | Chicago Rust Meetup
  • Rust Happy Hour
• 2025-07-17 | Hybrid (Redmond, WA, US) | Seattle Rust User Group
  • July, 2025 Computer Programming Language Panel (Special Event)
• 2025-07-17 | Nashville, TN, US | Music City Rust Developers
  • Rust on Bare Metal Series 1 : Introduction to Embedded Development
• 2025-07-23 | Austin, TX, US | Rust ATX
  • Rust Lunch - Fareground
• 2025-07-24 | Mountain View, CA, US | Hacker Dojo
  • RUST MEETUP at HACKER DOJO
• 2025-07-24 | México City, MX | Rust MX
  • Construyendo un Runtime Asíncrono desde Cero en Rust
• 2025-07-31 | Atlanta, GA, US | Rust Atlanta
  • Rust-Atl
• 2025-08-07 | Saint Louis, MO, US | STL Rust
  • macros!
• 2025-08-12 | San Francisco, CA, US | San Francisco Rust Study Group
  • Rust Hacking in Person

South America

• 2025-07-17 | Florianópolis, BR | Rust Brazil + Rust Floripa
  • Rust Floripa

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

Unfortunately -∞ doesn't fit in usize.

– Tomek Czajka on rust-users

Thanks to Kyllingene for the suggestion!

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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