If you’ve been wondering about those new S- tags, this post has an answer for you 
If you read nothing else in this post: if you are having issues with any part of the Rust project infrastructure (bots, PR queue, the play server, etc), reach out on the #rust-infra channel.
The core team is in the process of expanding the subteam structure to scale up management and empower more of the community. Part of the plan involves breaking up the existing Tools team into several more focused teams: Infrastructure, Cargo/crates.io, DevTools, and “Platform”. We’re doing this gradually, and by spinning up “unofficial” subteams to start, formalizing them once they’re up and running.
The first such team is for infrastructure. Its most fundamental goal is to ensure that PRs are landing and releases (including nightlies) are being produced. But ultimately its purview is intended to cover all aspects of Rust infrastructure:
- Pull request queue: facilitating reviews, Travis, Appveyor, Homu
- Highfive, rfcbot, nagbot, and other bots
- perf.rust-lang.org (currently down, work to bring it up is in progress)
- crates.io
- play.rust-lang.org
- rusty-dash (eventually)
To get started, we’re focusing primarily on the PR queue. That’s where the new S- statuses come in; we’re using them to track PR statuses and know when folks should be pinged. For now, these labels are experimental while we iterate; we’ll post more details about them once things have settled.
If you have questions, concerns, want to help out, or find that any piece of infrastructure is broken, please let us know! You can join the #rust-infra channel on irc.mozilla.org to inform us or join in the fun.