The Rust Release Process

Here's how Rust is currently released:

Bump the stable version number (T-6 days, Friday the week before)

Open a PR bumping the version number in src/version. r+ rollup=never this PR.

Mark it as rollup=never, because if it lands in a rollup as not the first PR then other pull requests in that rollup will be incorrectly associated with the prior release.

Promote branches (T-3 days, Monday)

Both promotions should happen on Monday. You can open both PRs at the same time, but make sure the stable promotion lands first.

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 origin
$ git push origin origin/beta:stable -f
# make sure that the release notes file is as fresh as possible
$ git checkout origin/master --

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

  • Update src/ci/channel to stable

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

After the PR is merged you'll need to start a dev release. Obtain AWS CLI credentials and run this command from the simpleinfra repository:

./ dev stable

As soon as this build is done create a blog post on Inside Rust asking for testing. The index is

Test rustup with:

RUSTUP_DIST_SERVER= rustup update stable

Master to beta

Run this command in the simpleinfra repository, while in a rust-lang/rust checkout (branch doesn't matter):


This script sets up the new rust-lang/cargo branch and force pushes the appropriate commit to rust-lang/rust's beta branch.

Once that's done, send a PR to the freshly created beta branch of rust-lang/rust which updates src/ci/channel to beta.

Master bootstrap update (T-2 day, Tuesday)

Send a PR to the master branch to:

  • Run ./ run src/tools/bump-stage0 to update the bootstrap compiler to the beta you created yesterday.

  • Remove references to the bootstrap and not(bootstrap) conditional compilation attributes. You can find all of them by installing ripgrep and running this command:

    rg '#!?\[.*\(bootstrap' -t rust

    The general guidelines (both for #[] and #![]) are:

    • Remove any item annotated with #[cfg(bootstrap)].
    • Remove any #[cfg(not(bootstrap))] attribute while keeping the item.
    • Remove any #[cfg_attr(bootstrap, $attr)] attribute while keeping the item.
    • Replace any #[cfg_attr(not(bootstrap), doc="$doc")] with $doc in the relevant documentation block (or in a new documentation block).
    • Replace any #[cfg_attr(not(bootstrap), $attr)] with #[$attr].

Release day (Thursday)

Decide on a time to do the release, T.

  • T-50m - Run the following command in a shell with AWS credentials in the simpleinfra repository:

    ./ prod stable

    That'll, in the background, schedule the promote-release binary to run on the production secrets (not the dev secrets). That'll sign everything, upload it, update the html index pages, and invalidate the CDN. Note that this takes about 30 minutes right now. Logs are in /opt/rcs/logs.

  • T-10m - Locally, tag the new release and upload it. Use "x.y.z release" as the commit message.

    $ git tag -u FA1BE5FE 1.3.0 $COMMIT_SHA
    $ git push rust-lang 1.3.0

    After this Update by triggering a build on GitHub Actions on the master branch.

  • T-2m - Merge blog post.

  • T - Tweet and post everything!

  • T+5m - Release and tag Cargo. From a rust-lang/rust checkout (script will checkout the stable branch automatically), run the following script from simpleinfra.

  • T+1hr Send a PR to the beta branch running ./ run src/tools/bump-stage0 to bump the boostrap compiler to the stable you just released.

Bask in your success.

Rebuilding stable pre-releases

If something goes wrong and we need to rebuild the stable artifacts, merge the PR on the stable branch of the rust-lang/rust repository. Once the commit is merged, issue the following command in a shell with AWS credentials on the simpleinfra repository:

./ dev stable --bypass-startup-checks

Publishing a nightly based off a try build

Sometimes a PR requires testing how it behaves when downloaded from rustup, for example after a manifest change. In those cases it's possible to publish a new nightly based off that PR on

Once the try build finishes grab the merge commit SHA and run the following command in a shell with AWS credentials on the simpleinfra repository:

./ dev nightly $MERGE_COMMIT_SHA

When the release process end you'll be able to install the new nightly with:

RUSTUP_DIST_SERVER= rustup toolchain install nightly