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.

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

Newsletters

• The Embedded Rustacean Issue #42
• This Week in Bevy - 2025-03-31

Project/Tooling Updates

• Fjall 2.8
• EtherCrab, the pure Rust EtherCAT MainDevice, version 0.6 released
• A process for handling Rust code in the core kernel
• api-version: axum middleware for header based version selection
• SALT: a VS Code Extension, seeking participants in a study on Rust usabilty

Observations/Thoughts

• Introducing Stringleton
• Rust Any Part 3: Finally we have Upcasts
• Towards fearless SIMD, 7 years later
• LLDB's TypeSystems: An Unfinished Interface
• Mutation Testing in Rust
• Embedding shared objects in Rust

Rust Walkthroughs

• Architecting and building medium-sized web services in Rust with Axum, SQLx and PostgreSQL
• Solving the ABA Problem in Rust with Hazard Pointers
• Building a CoAP application on Ariel OS
• How to Optimize your Rust Program for Slowness: Write a Short Program That Finishes After the Universe Dies
• Inside ScyllaDB Rust Driver 1.0: A Fully Async Shard-Aware CQL Driver Using Tokio
• Building a search engine from scratch, in Rust: part 2
• Introduction to Monoio: A High-Performance Rust Runtime
• Getting started with Rust on Google Cloud

Miscellaneous

• An AlphaStation's SROM
• Real-World Verification of Software for Cryptographic Applications
• Public mdBooks
• [video] Networking in Bevy with ECS replication - Hennadii
• [video] Intermediate Representations for Reactive Structures - Pete

Crate of the Week

This week's crate is candystore, a fast, persistent key-value store that does not require LSM or WALs.

Thanks to Tomer Filiba 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 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.

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.

• Rust Conf 2025 Call for Speakers | Closes 2025-04-29 11:59 PM PDT | Seattle, WA, US | 2025-09-02 - 2025-09-05

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

438 pull requests were merged in the last week

Compiler

• allow defining opaques in statics and consts
• avoid wrapping constant allocations in packed structs when not necessary
• perform less decoding if it has the same syntax context
• stabilize precise_capturing_in_traits
• uplift clippy::invalid_null_ptr_usage lint as invalid_null_arguments

Library

• allow spawning threads after TLS destruction
• override PartialOrd methods for bool
• simplify expansion for format_args!()
• stabilize const_cell

Rustdoc

• greatly simplify doctest parsing and information extraction
• rearrange Item/ItemInner

Clippy

• new lint: char_indices_as_byte_indices
• add manual_dangling_ptr lint
• respect #[expect] and #[allow] within function bodies for missing_panics_doc
• do not make incomplete or invalid suggestions
• do not warn about shadowing in a destructuring assigment
• expand obfuscated_if_else to support {then(), then_some()}.unwrap_or_default()
• fix the primary span of redundant_pub_crate when flagging nameless items
• fix option_if_let_else suggestion when coercion requires explicit cast
• fix unnested_or_patterns suggestion in let
• make collapsible_if recognize the let_chains feature
• make missing_const_for_fn operate on non-optimized MIR
• more natural suggestions for cmp_owned
• collapsible_if: prevent including preceeding whitespaces if line contains non blanks
• properly handle expansion in single_match
• validate paths in disallowed_* configurations

Rust-Analyzer

• allow crate authors to control completion of their things
• avoid relying on block_def_map() needlessly
• fix debug sourceFileMap when using cppvsdbg
• fix format_args lowering using wrong integer suffix
• fix a bug in orphan rules calculation
• fix panic in progress due to splitting unicode incorrectly
• use medium durability for crate-graph changes, high for library source files

Rust Compiler Performance Triage

Positive week, with a lot of primary improvements and just a few secondary regressions. Single big regression got reverted.

Triage done by @panstromek. Revision range: 4510e86a..2ea33b59

Summary:

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

• Tracking Issue for slice::array_chunks
• Stabilize cfg_boolean_literals
• Promise array::from_fn is generated in order of increasing indices
• Stabilize repr128
• Stabilize naked_functions
• Fix missing const for inherent pointer replace methods

Rust RFCs

• core::marker::NoCell in bounds (previously known an [sic] Freeze)

Cargo,

• Stabilize automatic garbage collection.

Other Areas

• No Items entered Final Comment Period this week for 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

• Allow &&, ||, and ! in cfg

Upcoming Events

Rusty Events between 2025-04-02 - 2025-04-30 🦀

Virtual

• 2025-04-02 | Virtual (Indianapolis, IN, US) | Indy Rust
  • Indy.rs - with Social Distancing
• 2025-04-03 | Virtual (Nürnberg, DE) | Rust Nurnberg DE
  • Rust Nürnberg online
• 2025-04-03 | Virtual | Ardan Labs
  • Communicate with Channels in Rust
• 2025-04-05 | Virtual (Kampala, UG) | Rust Circle Meetup
  • Rust Circle Meetup
• 2025-04-08 | Virtual (Dallas, TX, US) | Dallas Rust User Meetup
  • Second Tuesday
• 2025-04-10 | Virtual (Berlin, DE) | Rust Berlin
  • Rust Hack and Learn
• 2025-04-15 | Virtual (Washington, DC, US) | Rust DC
  • Mid-month Rustful
• 2025-04-16 | Virtual (Vancouver, BC, CA) | Vancouver Rust
  • Rust Study/Hack/Hang-out
• 2025-04-17 | Virtual and In-Person (Redmond, WA, US) | Seattle Rust User Group
  • April, 2025 SRUG (Seattle Rust User Group) Meetup
• 2025-04-22 | Virtual (Dallas, TX, US) | Dallas Rust User Meetup
  • Fourth Tuesday
• 2025-04-23 | Virtual (Cardiff, UK) | Rust and C++ Cardiff
  • Beyond embedded - OS development in Rust
• 2025-04-24 | Virtual (Berlin, DE) | Rust Berlin
  • Rust Hack and Learn
• 2025-04-24 | Virtual (Charlottesville, VA, US) | Charlottesville Rust Meetup
  • Part 2: Quantum Computers Can’t Rust-Proof This!"

Asia

• 2025-04-05 | Bangalore/Bengaluru, IN | Rust Bangalore
  • April 2025 Rustacean meetup
• 2025-04-22 | Tel Aviv-Yafo, IL | Rust 🦀 TLV
  • In person Rust April 2025 at Braavos in Tel Aviv in collaboration with StarkWare

Europe

• 2025-04-02 | Cambridge, UK | Cambridge Rust Meetup
  • Monthly Rust Meetup
• 2025-04-02 | Köln, DE | Rust Cologne
  • Rust in April: Rust Embedded, Show and Tell
• 2025-04-02 | München, DE | Rust Munich
  • Rust Munich 2025 / 1 - hybrid
• 2025-04-02 | Oxford, UK | Oxford Rust Meetup Group
  • Oxford Rust and C++ social
• 2025-04-02 | Stockholm, SE | Stockholm Rust
  • Rust Meetup @Funnel
• 2025-04-03 | Oslo, NO | Rust Oslo
  • Rust Hack'n'Learn at Kampen Bistro
• 2025-04-08 | Olomouc, CZ | Rust Moravia
  • 3. Rust Moravia Meetup (Real Embedded Rust)
• 2025-04-09 | Girona, ES | Rust Girona
  • Rust Girona Hack & Learn 04 2025
• 2025-04-09 | Reading, UK | Reading Rust Workshop
  • Reading Rust Meetup
• 2025-04-10 | Karlsruhe, DE | Rust Hack & Learn Karlsruhe
  • Karlsruhe Rust Hack and Learn Meetup bei BlueYonder
• 2025-04-15 | Leipzig, DE | Rust - Modern Systems Programming in Leipzig
  • Topic TBD
• 2025-04-15 | London, UK | Women in Rust
  • WIR x WCC: Finding your voice in Tech
• 2025-04-19 | Istanbul, TR | Türkiye Rust Community
  • Rust Konf Türkiye
• 2025-04-23 | London, UK | London Rust Project Group
  • Fusing Python with Rust using raw C bindings
• 2025-04-24 | Aarhus, DK | Rust Aarhus
  • Talk Night at MFT Energy
• 2025-04-24 | Edinburgh, UK | Rust and Friends
  • Rust and Friends (evening pub)
• 2025-04-24 | Manchester, UK | Rust Manchester
  • Rust Manchester April Code Night
• 2025-04-25 | Edinburgh, UK | Rust and Friends
  • Rust and Friends (daytime coffee)
• 2025-04-29 | Paris, FR | Rust Paris
  • Rust meetup #76

North America

• 2025-04-03 | Chicago, IL, US | Chicago Rust Meetup
  • Rust Happy Hour
• 2025-04-03 | Montréal, QC, CA | Rust Montréal
  • April Monthly Social
• 2025-04-03 | Saint Louis, MO, US | STL Rust
  • icu4x - resource-constrained internationalization (i18n)
• 2025-04-06 | Boston, MA, US | Boston Rust Meetup
  • Kendall Rust Lunch, Apr 6
• 2025-04-08 | New York, NY, US | Rust NYC
  • Rust NYC: Building a full-text search Postgres extension in Rust
• 2025-04-10 | Portland, OR, US | PDXRust
  • TetaNES: A Vaccination for Rust—No Needle, Just the Borrow Checker
• 2025-04-14 | Boston, MA, US | Boston Rust Meetup
  • Coolidge Corner Brookline Rust Lunch, Apr 14
• 2025-04-17 | Nashville, TN, US | Music City Rust Developers
  • Using Rust For Web Series 1 : Why HTMX Is Bad
• 2025-04-17 | Redmond, WA, US | Seattle Rust User Group
  • April, 2025 SRUG (Seattle Rust User Group) Meetup
• 2025-04-23 | Austin, TX, US | Rust ATX
  • Rust Lunch - Fareground
• 2025-04-25 | Boston, MA, US | Boston Rust Meetup
  • Ball Square Rust Lunch, Apr 25

Oceania

• 2025-04-09 | Sydney, NS, AU | Rust Sydney
  • Crab 🦀 X 🕳️🐇
• 2025-04-14 | Christchurch, NZ | Christchurch Rust Meetup Group
  • Christchurch Rust Meetup
• 2025-04-22 | Barton, AC, AU | Canberra Rust User Group
  • April Meetup

South America

• 2025-04-03 | Buenos Aires, AR | Rust en Español
  • Abril - Lambdas y más!

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

If you write a bug in your Rust program, Rust doesn’t blame you. Rust asks “how could the compiler have spotted that bug”.

– Ian Jackson blogging about Rust

Despite a lack of suggestions, llogiq is quite 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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Discuss on r/rust