Hello and welcome to another issue of This Week in Rust! Rust is a systems language pursuing the trifecta: safety, concurrency, and speed. 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

News & Blog Posts

@RustStatus - Official Twitter account to track outages of Crates.io, rustup, bors, and nightly breakage.
Announcing Tectonic: A complete, modernized, self-contained TeX/LaTeX engine.
Sccache for caching Rust compilation.
Rust: A Scala engineer's perspective.
Overhead analysis of the RTFM framework. RTFM is a framework for building concurrent applications, for ARM Cortex-M MCUs.
Debug Rust on Windows with Visual Studio Code and the MSVC debugger.
Query structure in chalk. Chalk is a PROLOG-ish interpreter written in Rust, intended eventually for use in the compiler.
Notes on building Noise: a JSON search engine written in Rust.
Continuous integration and code coverage report for a Rust project.
Rust in TiKV. TiKV is a distributed Key-Value database written in Rust.
[video] Helix: Build and deploy a Ruby native extension with Rust in 10 minutes.
Rust support for KDevelop being worked on as a GSoC project.
This week in Rust docs 58.

Crate of the Week

Sadly, we had no nominations this week, so stay tuned for next week!

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.

Rust libz blitz status update 2017-05-27. Contribution opportunities are available.
The log crate just completed its evaluation, generating a ton of easy-tagged issues.
Rust cookbook needs a lot of help!
Help wanted: Rust for embedded development: Where we are and what’s missing.
[easy] i3status-rust is looking for contributors to make i3 window manager more awesome!
rust: Get test suite working with wasm.
gutenberg: Make a SyntaxSet pool. Gutenberg is an opinionated static site generator written in Rust.

If you are a Rust project owner and are looking for contributors, please submit tasks here.

Updates from Rust Core

94 pull requests were merged in the last week.

New Contributors

Charlie Somerville
Dmitry Vyukov
Ian Douglas Scott
Matthew
matthewjasper

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. This week's FCPs are:

[disposition: merge] Specify #[repr(transparent)].
[disposition: close] Implement adaptive hashing for HashMap.

New RFCs

Future-proofing enums/structs with #[non_exhaustive] attribute.
Const/static type annotation elision. Allow elision of type annotations in many cases for const and static items, as part of the ergonomics initiative.
Make the assert! macro generic to all expressions, and extend the readability of debug dumps.

Style RFCs

Style RFCs are part of the process for deciding on style guidelines for the Rust community and defaults for Rustfmt. The process is similar to the RFC process, but we try to reach rough consensus on issues (including a final comment period) before progressing to PRs. Just like the RFC process, all users are welcome to comment and submit RFCs. If you want to help decide what Rust code should look like, come get involved!

We're making good progress and the style is coming together. If you want to see the style in practice, check out our example or use the Integer32 Playground and select 'Proposed RFC' from the 'Format' menu. Be aware that implementation is work in progress.

Issues in final comment period: