09 Apr 2026

feedPlanet Mozilla

Andreas Farre: BuildCache now works with mach

I'm happy to announce that buildcache is now a first-class compiler cache in mach. This has been a long time coming, and I'm excited to finally see it land.

For those unfamiliar, buildcache is a compiler cache that can drastically cut down your rebuild times by caching compilation results. It's similar to ccache, but even more so sccache, in that it supports C/C++ out of the box, as well as Rust. It has some nice unique properties of its own though, which we'll look at more closely in following posts.

Getting started

Setting it up is straightforward. Just add the following to your mozconfig:

ac_add_options --with-ccache=buildcache

Then build as usual:

./mach build

That's it.

Give it a try

If you run into any issues, please file a bug and tag me. I'd love to hear how it works out for people, and any rough edges you might hit.

09 Apr 2026 12:00am GMT

08 Apr 2026

feedPlanet Mozilla

Firefox Tooling Announcements: MozPhab 2.12.0 Released

Bugs resolved in Moz-Phab 2.12.0:

Discuss these changes in #engineering-workflow on Slack or #Conduit Matrix.

1 post - 1 participant

Read full topic

08 Apr 2026 6:04pm GMT

This Week In Rust: This Week in Rust 646

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
Foundation
Newsletters
Project/Tooling Updates
Observations/Thoughts
Rust Walkthroughs
Miscellaneous

Crate of the Week

This week's crate is aimdb-core, a type-safe and platform-agnostic data pipeline where the Rust type system is the schema and trait implementations define its behavior.

Thanks to sounds.like.lx 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.

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.

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

479 pull requests were merged in the last week

Compiler
Library
Cargo
Clippy
Rust-Analyzer
Rust Compiler Performance Triage

A shorter week than normal (probably due to later perf triage last week). Overall fairly small changes scattered across various PRs, though the net effect was slightly positive (-0.5% avg change). All changed ended up either mixed or improvements this week.

Triage done by @simulacrum. Revision range: cf7da0b7..e73c56ab

0 Regressions, 3 Improvements, 8 Mixed; 5 of them in rollups 26 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:

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

Cargo

Compiler Team (MCPs only)

No Items entered Final Comment Period this week for Rust RFCs, Language Reference, Language Team, Leadership Council 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

Upcoming Events

Rusty Events between 2026-04-08 - 2026-05-06 🦀

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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

Rust tried to have polymorphic generics in the early pre-1.0 days, and they quite reasonably gave up because it was too much work. For real Swift, great fucking working for getting all of this to work!

- Aria Desires on her blog

llogiq thanks himself for the suggestion!

Please submit quotes and vote for next week!

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Discuss on r/rust

08 Apr 2026 4:00am GMT