The Rust Release Process

Here’s how Rust is currently released:

Promote beta to stable (T-3 days, Monday)

Promote beta to stable. Temporarily turn off GitHub branch protection for the stable branch in rust-lang/rust repo. In your local Rust repo:

$ git fetch rust-lang
$ git push rust-lang rust-lang/beta:stable -f

Re-enable branch protection for the stable branch. Send a PR to rust-lang/rust on the stable branch making the following changes:

Once the PR is sent, r+ it and give it a high p=1000.

The stable build will not deploy automatically to prod. The rust-central-station repository is configured to upload to dev every hour if it detects a change. You should be able to browse changes in dev.

As soon as this build is done post a message to irlo asking for testing. The index is and our URL is then

Test rustup with

RUSTUP_DIST_SERVER= rustup update stable

If something goes wrong, and we rebuild stable artifacts, you’ll need to invalidate the dev-static bucket for RCS to re-release it.

  1. Download https://dev-static.rust-lang/dist/channel-rust-1.35.0.toml The version number must be less than the current release, but otherwise doesn’t matter.
  2. Rename the file locally to channel-rust-stable.toml
  3. Upload the file to the dev-static bucket into the dist folder, replacing channel-rust-stable.toml.
  4. Go to CloudFront in AWS, to the dev-static bucket, and issue an invalidation for “/dist/channel-rust-stable.toml”. This is necessary until is fixed.
  5. (optional) login to central station, and run the following. This starts the dev-static promotion immediately, vs. waiting till the next hour.
docker exec -d -it rcs bash -c 'promote-release /tmp/stable stable /data/secrets-dev.toml 2>&1 | logger --tag release-stable'

Promote master to beta (T-2 days, Tuesday)

Create a new branch on rust-lang/cargo for the new beta. Here, rust-lang is the remote for Replace YY with the minor version of master. First determine the branch point for cargo in rust-lang/rust, and then create a new branch:

$ cd rust
$ git fetch rust-lang
$ CARGO_SHA=`git rev-parse rust-lang/master:src/tools/cargo`
$ cd src/tools/cargo
$ git branch rust-1.YY.0 $CARGO_SHA
$ git push origin rust-1.YY.0

You’ll need to temporarily disable branch protection on GitHub to push the new branch.

In theory one day we’ll do the same for rust-lang/rls, but for now we haven’t done this yet.

Temporarily disable banch protection on GitHub for the beta branch of the Rust repo. Promote rust-lang/rust’s master branch to beta as with yesterday:

$ git fetch rust-lang
$ git push rust-lang rust-lang/master:beta -f

Re-enable branch protection on GitHub. Send a PR to the freshly created beta branch of rust-lang/rust which:

Note that you probably don’t want to update the RLS if it’s working, but if it’s not working beta won’t land and it’ll need to get updated. After this PR merges (through @bors) the beta should be automatically released.

Master bootstrap update (T-1 day, Wednesday)

Write a new blog post, update rust-www, and update rust-forge. Submit PRs for tomorrow.

Send a PR to the master branch to:

Release day (Thursday)

Decide on a time to do the release, T.

Bask in your success.

Update dependencies (T+1 day, Friday)

In the repo:

$ cd src
$ cargo update

The very ambitious can use and update through breaking changes.