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.
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Updates from Rust Community
Official
Project/Tooling Updates
- pquantum.dev: Post-Quantum Cryptography in Rust
- haproxy-spoe-rs: A Rust SPOA Agent Library for HAProxy
- Fresh 0.2.23: Terminal IDE adds Windows-1251 encoding, customizable status bar, and faster file finder
- KAIO v0.2.0: Writing GPU Kernels in Rust at 92.5% of cuBLAS
- RustNet: A Real-Time Network Traffic Analysis TUI
- AimDB: The Next Era of Software Architecture Is Data-First
- tailscale-rs v0.2.0: our new Rust library preview
- Sinbo: a CLI snippet manager, store code snippets locally with fuzzy search, encryption, and shell completions
- flodl v0.4.0: heterogeneous multi-GPU DDP with faster training and better convergence than solo GPU
Observations/Thoughts
- The acyclic e-graph: Cranelift's mid-end optimizer
- Rust should have stable tail calls
- Flat Error Codes Are Not Enough
- No one owes you supply-chain security
- Everything Should Be Typed: Scalar Types Are Not Enough
- Borrow-checking surprises
- A Roadmap for Building an Extended Standard Library for Rust
- Okay, what ACTUALLY uses Rust?
- [audio] Netstack.FM episode 34 — Tokio with Carl Lerche (Ep 5 Remastered)
Rust Walkthroughs
- Untangling Tokio and Rayon in production: From 2s latency spikes to 94ms flat
- Understanding Traceroute
- Bringing Rust to the Pixel Baseband
- Fixing DNS tail latency with a 5-line config and a 50-line function
- Debloat your async Rust
- Learn Rust Ownership and Borrowing By Building Mini Grep
- Profiling Rust: A Flamegraph vs PGO, BOLT, and Native CPU Targeting
- Bulletproof Rust Web: An opinionated guide to production-grade Axum applications
- A minimal VMM in Rust with KVM
- claudectl: Building a TUI Dashboard for AI Coding Agents in Rust
- [video] Build with Naz : Eliminate busy waiting with Rust Condvar
Crate of the Week
This week's crate is Myth Engine, a high-performance, cross-platform rendering engine.
Thanks to Pan Xinmiao 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, Cargo, Rustup or Rust language RFCs.
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.
No Calls for participation were submitted this week.
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 Bluesky 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.
- EuroRust | CFP open until 2026-04-27 | Barcelona, Spain | 2026-10-14 - 2026-10-17
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 Bluesky or Mastodon!
Updates from the Rust Project
519 pull requests were merged in the last week
Compiler
- add
#![unstable_removed(..)]attribute to track removed features - add suggestion to
.to_owned()used onCowwhen borrowing - avoid stack overflow in FindExprBySpan
- enable
#[diagnostic::on_const]for local impls - introduce a
#[diagnostic::on_unknown]attribute - reduce size of
ImportData ty::Aliasrefactor- semantic checks of
implrestrictions - stabilize s390x vector registers
- store
chunk_domain_sizeexplicitly inChunk
Library
- add
const Defaultimpls forLazyCellandLazyLock - constify some
Iteratormethods - constify DoubleEndedIterator
- constify
Step for NonZero<u*> - don't leak internal temporaries from
dbg! - explicitly forget the zero remaining elements in
vec::IntoIter::fold() - impl const Residual for ControlFlow
- initial functions to start on transmute v2
- introduce
#[diagnostic::on_move]onRc - make
Box/Rc/Arc::into_arrayallocator-aware (and add doctest) - stabilize feature
int_lowest_highest_one - stabilize feature
isolate_most_least_significant_one - stabilize feature
uint_bit_width
Cargo
- clean: add target directory validation
manifest: allow git dependency alongside alternate registryauth: add auth scheme hint to token rejected error for alt registriescore: useclosest_msgto suggest similar member name for mistyped-plints: ignoreunused_crate_dependenciesstatustoml: force script edition warnings on quiet- copy cargo clean target-dir validation tests to
clean_new_layout.rs - never include use extra-filename in build scripts
- support target.'cfg(..)'.rustdocflags analogously to rustflags
Rustdoc
- fix pattern types rendering
- dep-info for standalone markdown inputs
- inherit inline attributes for declarative macros
Clippy
fn_to_numeric_cast_any: do not warn cast to raw pointer- even more fixes for handling of macros
- extend
manual_filterto coverand_then - fix
unused_asyncfalse positive for stubs with args - fix wrong suggestion for
println_empty_stringwith non-parenthesis delimiters - truncate constants to target type in comparison
Rust-Analyzer
- changes to build scripts and config.toml should always refresh
- demoting completion relevance when an inherent impl already exists
- enhance runnable command placeholders
- support
implandmutrestrictions - fix
[env]in.cargo/config.tomloverriding process environment variables - fix rustfmt relative custom command
- MIR evaluation of sized &T with recursive const fn
- check coercion, not unification, in "Fill
structfields", as the criteria to use an existing local as the field's value - complete variants of hidden enums through public aliases
- consider the context of the path for
ImportAssets - diagnose cfged-out crate
- disable the fix for missing-fields when the fields are private
- enable vscode suggest in strings
- fix
ref_matchposition when keyword prefix - improve add some on block like expression
- improve label on
add_missing_match_armsassist - no complete term expressions on qualified path
- no deref index-expr for
extract_function - no imports on type anchor qualified path
- parse
cfg_attrandcfgspecially - handle token mutability in edit flow as well
- migrate extract
structfromenumvariant to new SyntaxEditor and Port whitespace heuristics to SyntaxEditor - replace make from generate single field
structfrom with SyntaxFactory - unwrap unnecessary result return type in
view_crate_graph
Rust Compiler Performance Triage
This week was negative, mainly caused by a type system fix and because we had to temporarily revert some attribute cleanups that previously improved performance.
Triage done by @panstromek. Revision range: e73c56ab..dab8d9d1
Summary:
| (instructions:u) | mean | range | count |
|---|---|---|---|
| Regressions ❌ (primary) |
0.4% | [0.2%, 0.7%] | 46 |
| Regressions ❌ (secondary) |
0.5% | [0.1%, 2.3%] | 102 |
| Improvements ✅ (primary) |
-0.5% | [-0.6%, -0.4%] | 4 |
| Improvements ✅ (secondary) |
-0.4% | [-0.6%, -0.2%] | 5 |
| All ❌✅ (primary) | 0.4% | [-0.6%, 0.7%] | 50 |
4 Regressions, 1 Improvement, 5 Mixed; 6 of them in rollups 41 artifact comparisons made in total
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
- Verify that penultimate segment of enum variant path refers to enum if it has args
- deprecate
std::charconstants and functions impl DefaultforRepeatN- Make std::fs::File Send on UEFI
Cargo
Compiler Team (MCPs only)
- Optimize
repr(Rust)enums by omitting tags in more cases involving uninhabited variants. - Proposal for a dedicated test suite for the parallel frontend
- Promote tier 3 riscv32 ESP-IDF targets to tier 2
- Proposal for Adapt Stack Protector for Rust
Rust RFCs
Leadership Council
No Items entered Final Comment Period this week for Language Reference, Language Team 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
- No New or Updated RFCs were created this week.
Upcoming Events
Rusty Events between 2026-04-15 - 2026-05-13 🦀
Virtual
- 2026-04-15 | Hybrid (Vancouver, BC, CA) | Vancouver Rust
- 2026-04-15 | Virtual (Girona, ES) | Rust Girona
- 2026-04-16 | Hybrid (Seattle, WA, US) | Seattle Rust User Group
- 2026-04-19 | Virtual (Dallas, TX, US) | Dallas Rust User Meetup
- 2026-04-21 | Virtual (Washington, DC, US) | Rust DC
- 2026-04-22 | Virtual (Girona, ES) | Rust Girona
- 2026-04-23 | Virtual (Amsterdam, NL) | Bevy Game Development
- 2026-04-23 | Virtual (Berlin, DE) | Rust Berlin
- 2026-04-24 | Virtual (Nairobi, KE) | RustaceansKenya
- 2026-04-28 | Virtual (Dallas, TX, US) | Dallas Rust User Meetup
- 2026-04-28 | Virtual (London, UK) | Women in Rust
- 2026-04-29 | Virtual (Girona, ES) | Rust Girona
- 2026-05-01 | Virtual (Nürnberg, DE) | Rust Nuremberg
- 2026-05-02 | Virtual (Kampala, UG) | Rust Circle Meetup
- 2026-05-03 | Virtual (Dallas, TX, US) | Dallas Rust User Meetup
- 2026-05-06 | Virtual (Girona, ES) | Rust Girona
- 2026-05-06 | Virtual (Indianapolis, IN, US) | Indy Rust
- 2026-05-07 | Virtual (Berlin, DE) | Rust Berlin
- 2026-05-07 | Virtual (Nürnberg, DE) | Rust Nuremberg
- 2026-05-12 | Virtual (Dallas, TX, US) | Dallas Rust User Meetup
- 2026-05-12 | Virtual (London, GB) | Women in Rust
- 2026-05-13 | Virtual (Girona, ES) | Rust Girona
Asia
- 2026-04-17 | Bangalore, IN | Rust India
- 2026-04-18 | Bangalore, IN | Rust India
- 2026-05-13 | Malaysia, MY | Rust Meetup Malaysia
Europe
- 2026-04-16 | Berlin, DE | Rust Berlin
- 2026-04-21 | Leipzig, DE | Rust - Modern Systems Programming in Leipzig
- 2026-04-23 | Aarhus, DK | Rust Aarhus
- 2026-04-24 - 2026-04-26 | Augsburg, DE | Rust Meetup Augsburg
- 2026-04-25 | Stockholm, SE | Stockholm Rust
- 2026-04-29 | Paris, FR | Paris Rustaceans
- 2026-04-30 | Manchester, GB | Rust Manchester
- 2026-05-02 | Augsburg, DE | Rust Munich and Rust Augsburg
- 2026-05-04 | Amsterdam, NH, NL | Rust Developers Amsterdam Group
- 2026-05-04 | Frankfurt, DE | Rust Rhein-Main
- 2026-05-05 | Olomouc, CZ | Rust Moravia
North America
- 2026-04-15 | Hybrid (Vancouver, BC, CA) | Vancouver Rust
- 2026-04-16 | Hybrid (Seattle, WA, US) | Seattle Rust User Group
- 2026-04-16 | Mountain View, CA, US | Hacker Dojo
- 2026-04-16 | Nashville, TN, US | Music City Rust Developers
- 2026-04-18 | Boston, MA, US | Boston Rust Meetup
- 2026-04-20 - 2026-04-22 | Portland, OR | Tokio
- 2026-04-21 | San Francisco, CA, US | San Francisco Rust Study Group
- 2026-04-22 | Austin, TX, US | Rust ATX
- 2026-04-22 | New York, NY, US | Rust NYC
- 2026-04-22 | Portland, OR | Apache DataFusion Meetup
- 2026-04-23 | Los Angeles, CA, US | Rust Los Angeles
- 2026-04-25 | Boston, MA, US | Boston Rust Meetup
- 2026-04-28 | New York, NY, US | Rust NYC
- 2026-04-30 | Atlanta, GA, US | Rust Atlanta
- 2026-05-07 | Saint Louis, MO, US | STL Rust
South America
- 2026-04-17 | Rio de Janeiro, BR | Meetups Rust RJ
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
the amount of times that I spend 15 min in the docs + coding which end up in a monstrous
or().flatten().map().is_ok_and()only to get slapped by clippy sayingreplace your monster with this single function pleaseis way too high 😀
– Teufelchen on RIOT off-topic matrix chat
Thanks to chrysn for the suggestion!
Please submit quotes and vote for next week!
This Week in Rust is edited by:
- nellshamrell
- llogiq
- ericseppanen
- extrawurst
- U007D
- mariannegoldin
- bdillo
- opeolluwa
- bnchi
- KannanPalani57
- tzilist
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