posts: announce rustup 1.28.0

posts/2025-03-02-Rustup-1.28.0.md

@@ -0,0 +1,112 @@
+---
+layout: post
+title: "Announcing Rustup 1.28.0"
+author: The Rustup Team
+---
+
+The rustup team is happy to announce the release of rustup version 1.28.0.
+[Rustup][install] is the recommended tool to install [Rust][rust], a programming language that is empowering everyone to build reliable and efficient software.
+
+## What's new in rustup 1.28.0
+
+This new release of rustup has been a long time in the making and comes with substantial changes.
+
+Before digging into the details, it is worth mentioning that [Chris Denton](https://github.com/chrisdenton) has joined the team.
+Chris has a lot of experience contributing to Windows-related parts of the Rust Project -- expertise we were previously lacking -- so we're happy to have him on board to help address Windows-specific issues.
+
+The following improvements might require changes to how you use rustup:
+
+- rustup will no longer automatically install the active toolchain if it is not installed.
+
+  - To ensure its installation, run `rustup toolchain install` with no arguments.
+  - The following command installs the active toolchain both before and after this change:
+    ```sh
+    rustup show active-toolchain || rustup toolchain install
+    # Or, on older versions of PowerShell:
+    rustup show active-toolchain; if ($LASTEXITCODE -ne 0) { rustup toolchain install }
+    ```
+
+- Installing a host-incompatible toolchain via `rustup toolchain install` or `rustup default` will
+  now be rejected unless you explicitly add the `--force-non-host` flag.
+
+Rustup now officially supports the following host platforms:
+
+- `aarch64-pc-windows-msvc`
+- `loongarch64-unknown-linux-musl`
+
+This release also comes with various quality-of-life improvements, to name a few:
+
+- `rustup show`'s output format has been cleaned up, making it easier to find out about your toolchains' status.
+- `rustup doc` now accepts a flag and a topic at the same time, enabling quick navigation to specific parts of more books.
+- rustup's `remove` subcommands now support more aliases such as `rm` and `del`.
+- Basic support for nushell has been added.
+
+We have additionally made the following internal changes:
+
+- The default download backend has been changed from reqwest with native-tls to reqwest with rustls.
+  - `RUSTUP_USE_CURL` and `RUSTUP_USE_RUSTLS` can still be used to change the download backend
+    if the new backend causes issues. If issues do happen, please [let us know](https://github.com/rust-lang/rustup/issues/3806).
+  - The default backend now uses rustls-platform-verifier to verify server certificates, taking
+    advantage of the platform's certificate store on platforms that support it.
+- When creating proxy links, rustup will now try symlinks first and fall back to hardlinks,
+  as opposed to trying hardlinks first.
+- A new `RUSTUP_LOG` environment variable can be used to control tracing-based logging in
+  rustup binaries. See the [dev guide](https://rust-lang.github.io/rustup/dev-guide/tracing.html) for more details.
+
+Finally, there are some notable changes to our [official website][install] as well:
+
+- The overall design of the website has been updated to better align with the Rust Project's branding.
+- It is now possible to download the prebuilt `rustup-init.sh` installer for the `aarch64-pc-windows-msvc` host platform via https://win.rustup.rs/aarch64.
+
+Further details are available in the [changelog]!
+
+## How to update
+
+If you have a previous version of rustup installed, getting rustup 1.28.0 is as easy as stopping any programs which may be using Rustup (e.g. closing your IDE) and running:
+
+```console
+$ rustup self update
+```
+
+Rustup will also automatically update itself at the end of a normal toolchain update:
+
+```console
+$ rustup update
+```
+
+If you don't have it already, you can [get rustup][install] from the appropriate page on our website.
+
+Rustup's documentation is also available in [the rustup book][book].
+
+## Caveats
+
+Rustup releases can come with problems not caused by rustup itself but just due to having a new release.
+As such, we recommend paying attention to the following potential issues in particular:
+
+- Anti-malware scanners might be blocking rustup or stopping it from creating or copying files
+  (especially when installing `rust-docs`, since it contains many small files).
+
+- In your CI environment, rustup might fail when trying to perform a self-update.
+
+  This is a [known issue](https://github.com/rust-lang/rustup/issues/3709),
+  and in the case where this issue does occur, we recommend applying the following workaround at the beginning of your workflow:
+
+  ```console
+  $ rustup set auto-self-update disable
+  ```
+
+  Also, starting from 1.28.0, rustup will no longer attempt to self-update in CI environments,
+  so this workaround should not be necessary in the future.
+
+These issues should be automatically resolved in a few weeks when the anti-malware scanners are updated to be aware of the new rustup release,
+and the hosted version is updated across all CI runners.
+
+## Thanks
+
+Thanks again to all the [contributors] who made rustup 1.28.0 possible!
+
+[book]: https://rust-lang.github.io/rustup/
+[changelog]: https://github.com/rust-lang/rustup/blob/stable/CHANGELOG.md
+[contributors]: https://github.com/rust-lang/rustup/blob/stable/CHANGELOG.md#detailed-changes
+[install]: https://rustup.rs
+[rust]: https://www.rust-lang.org