fix(shim): update mise-shim.exe during self-update on Windows by jdx · Pull Request #8075 · jdx/mise

jdx · 2026-02-09T21:33:12Z

Summary

After mise self-update updates mise.exe on Windows, also extract and update mise-shim.exe from the same release archive
Non-fatal: if the shim update fails, a warning is emitted but the overall self-update still succeeds
Uses existing zip, tempfile, and HTTP client — no new dependencies

Fixes the issue where mise self-update only updated mise.exe but left mise-shim.exe at the old version, requiring users to manually download it from GitHub releases. Reported after #8045 added native .exe shim mode.

Test plan

Verify cargo clippy --workspace passes (confirmed locally)
Test on Windows: mise self-update --force updates both mise.exe and mise-shim.exe
Test on Windows: if mise-shim.exe is missing from the archive, a warning is printed but the update succeeds
Verify non-Windows builds are unaffected (all new code is #[cfg(windows)])

🤖 Generated with Claude Code

Note

Medium Risk
Touches the Windows self-update path and adds new download/extract/replace logic for an executable; failures are non-fatal but a bug could leave the shim outdated or not replaced as expected.

Overview
On Windows, mise self-update now also updates mise-shim.exe after updating mise.exe by downloading the matching release .zip, verifying its zipsign signature, extracting mise/bin/mise-shim.exe, and atomically replacing the local shim (non-fatal on failure).

This adds a Windows-only dependency on zipsign-api and updates Cargo.lock accordingly, plus a small tweak to version styling output to reuse the string value.

^{Written by Cursor Bugbot for commit 7267f26. This will update automatically on new commits. Configure here.}

After the main binary update succeeds on Windows, download the same release zip and extract mise-shim.exe alongside the updated mise.exe. This is non-fatal — if the shim update fails, a warning is emitted but the overall self-update still succeeds. Fixes the issue where `mise self-update` only updated mise.exe but left mise-shim.exe at the old version, requiring manual download. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

gemini-code-assist · 2026-02-09T21:33:29Z

Summary of Changes

Hello @jdx, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request enhances the "mise" self-update mechanism specifically for Windows users. It resolves a previous inconsistency by ensuring that when "mise" updates itself, its associated "mise-shim.exe" is also automatically updated from the release archive. This provides a more seamless and complete update experience, preventing users from needing to manually manage shim versions.

Highlights

Windows Shim Update: Implemented automatic updating of "mise-shim.exe" on Windows during "mise self-update" to ensure both "mise.exe" and its shim are kept current.
Robustness: The "mise-shim.exe" update process is non-fatal; if it fails, a warning is logged, but the main "mise" update still completes successfully.
Resource Utilization: Leverages existing "zip", "tempfile", and HTTP client functionalities, avoiding the introduction of new dependencies.
Bug Fix: Addresses a known issue where "mise self-update" on Windows would only update "mise.exe", leaving "mise-shim.exe" outdated, requiring manual intervention.

Changelog

src/cli/self_update.rs
- Introduced a call to "Self::update_mise_shim" within the "self_update" method, specifically for Windows builds, to handle the shim executable update after "mise.exe" is updated.
- Added a new "#[cfg(windows)]" function "update_mise_shim" responsible for downloading the release archive, extracting "mise-shim.exe", and replacing the existing shim.
- Implemented error handling in "update_mise_shim" to log a warning and proceed if "mise-shim.exe" is not found in the downloaded archive.

Activity

The pull request was generated using Claude Code, an AI tool.
The author has provided a detailed test plan covering Windows-specific update scenarios and verification for non-Windows builds.

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Copilot

Pull request overview

Updates Windows self-update behavior so that mise self-update refreshes both mise.exe and the native mise-shim.exe from the same release archive, while keeping shim failures non-fatal.

Changes:

Print updated version using a stored String for reuse.
Add Windows-only logic to download the release ZIP and extract mise-shim.exe.
Emit warnings (without failing the overall update) when shim update fails or shim is missing from the archive.

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Copilot · 2026-02-09T21:34:16Z

src/cli/self_update.rs

+        tokio::task::block_in_place(|| {
+            tokio::runtime::Handle::current().block_on(HTTP.download_file(&url, &zip_path, None))
+        })?;


tokio::task::block_in_place and tokio::runtime::Handle::current() will panic if this code is executed outside a Tokio runtime (or inside a current-thread runtime where block_in_place is unsupported). Consider making update_mise_shim async and await the download from the existing async context, or use a runtime-agnostic approach (e.g., if a Tokio handle isn't available, create a dedicated runtime to block_on, or provide a synchronous download path).

Suggested change

tokio::task::block_in_place(|| {

tokio::runtime::Handle::current().block_on(HTTP.download_file(&url, &zip_path, None))

})?;

if let Ok(handle) = tokio::runtime::Handle::try_current() {

handle.block_on(HTTP.download_file(&url, &zip_path, None))?;

} else {

let rt = tokio::runtime::Runtime::new()?;

rt.block_on(HTTP.download_file(&url, &zip_path, None))?;

}

Copilot · 2026-02-09T21:34:17Z

src/cli/self_update.rs

+        let mut buf = Vec::new();
+        shim_entry.read_to_end(&mut buf)?;
+        xx::file::write(&dest, &buf)?;


Writing the shim by buffering the entire file and then writing directly to the final destination increases the chance of leaving a partially-written mise-shim.exe if the process is interrupted mid-write. Prefer an atomic update pattern (write to a temporary file in the same directory, then rename/replace), and ideally stream from the ZIP entry into the temp file to avoid the extra buffering.

gemini-code-assist

Code Review

This pull request adds a helpful feature to update mise-shim.exe on Windows during a self-update. The overall approach of downloading the release archive and extracting the shim is correct. However, I've identified a critical bug in the URL construction that would cause the download to fail. Additionally, I've suggested an improvement to make the new function asynchronous for better performance and idiomatic code, which requires changes in two places. My review includes code suggestions to address these points.

gemini-code-assist · 2026-02-09T21:36:39Z

src/cli/self_update.rs

+    #[cfg(windows)]
+    fn update_mise_shim(version: &str) -> Result<()> {
+        use crate::http::HTTP;
+        use std::io::Read;
+
+        let url = format!(
+            "https://github.com/jdx/mise/releases/download/{version}/mise-{version}-{}-{}.zip",
+            *OS, *ARCH,
+        );
+        debug!("Downloading mise-shim.exe from {url}");
+
+        let temp_dir = tempfile::tempdir()?;
+        let zip_path = temp_dir.path().join("mise.zip");
+        tokio::task::block_in_place(|| {
+            tokio::runtime::Handle::current().block_on(HTTP.download_file(&url, &zip_path, None))
+        })?;
+
+        let file = fs::File::open(&zip_path)?;
+        let mut archive = zip::ZipArchive::new(file)?;
+
+        let mut shim_entry = match archive.by_name("mise/bin/mise-shim.exe") {
+            Ok(entry) => entry,
+            Err(_) => {
+                warn!("mise-shim.exe not found in release archive, skipping");
+                return Ok(());
+            }
+        };
+
+        let dest = env::MISE_BIN
+            .parent()
+            .expect("MISE_BIN should have a parent directory")
+            .join("mise-shim.exe");
+        let mut buf = Vec::new();
+        shim_entry.read_to_end(&mut buf)?;
+        xx::file::write(&dest, &buf)?;
+
+        debug!("Updated mise-shim.exe at {}", dest.display());
+        Ok(())
+    }


This new function has a critical bug and a potential improvement:

Incorrect URL (Critical): The URL for downloading the release archive is constructed incorrectly. Release tags and asset names on GitHub for mise are prefixed with a v (e.g., v2024.5.1), but the version variable here does not include it. This will cause downloads to fail with a 404 error.

Blocking in async context (Improvement): The function is synchronous and uses tokio::task::block_in_place. Since it's called from an async context, it's better to make it async and await the download directly.

The suggestion below addresses both points. Note that you will also need to await the call to this function in run(), for which I've left a separate comment.

#[cfg(windows)] async fn update_mise_shim(version: &str) -> Result<()> { use crate::http::HTTP; use std::io::Read; let url = format!( "https://github.com/jdx/mise/releases/download/v{version}/mise-v{version}-{}-{}.zip", *OS, *ARCH, ); debug!("Downloading mise-shim.exe from {url}"); let temp_dir = tempfile::tempdir()?; let zip_path = temp_dir.path().join("mise.zip"); HTTP.download_file(&url, &zip_path, None).await?; let file = fs::File::open(&zip_path)?; let mut archive = zip::ZipArchive::new(file)?; let mut shim_entry = match archive.by_name("mise/bin/mise-shim.exe") { Ok(entry) => entry, Err(_) => { warn!("mise-shim.exe not found in release archive, skipping"); return Ok(()); } }; let dest = env::MISE_BIN .parent() .expect("MISE_BIN should have a parent directory") .join("mise-shim.exe"); let mut buf = Vec::new(); shim_entry.read_to_end(&mut buf)?; xx::file::write(&dest, &buf)?; debug!("Updated mise-shim.exe at {}", dest.display()); Ok(()) }

gemini-code-assist · 2026-02-09T21:36:40Z

src/cli/self_update.rs

+            if let Err(e) = Self::update_mise_shim(&version) {
+                warn!("Failed to update mise-shim.exe: {e}");
+            }


To accommodate the suggested change of making update_mise_shim an async function, this call needs to be awaited.

Suggested change

if let Err(e) = Self::update_mise_shim(&version) {

warn!("Failed to update mise-shim.exe: {e}");

}

if let Err(e) = Self::update_mise_shim(&version).await {

warn!warn("Failed to update mise-shim.exe: {e}");

}

src/cli/self_update.rs

github-actions · 2026-02-09T21:50:12Z

Hyperfine Performance

`mise x -- echo`

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
`mise-2026.2.8 x -- echo`	23.6 ± 0.9	22.9	36.2	1.00
`mise x -- echo`	23.9 ± 0.4	23.0	26.3	1.01 ± 0.04

`mise env`

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
`mise-2026.2.8 env`	23.1 ± 0.5	22.4	27.3	1.00
`mise env`	23.3 ± 0.9	22.6	37.0	1.01 ± 0.04

`mise hook-env`

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
`mise-2026.2.8 hook-env`	23.7 ± 0.4	23.0	25.8	1.00
`mise hook-env`	23.9 ± 0.3	23.2	24.9	1.01 ± 0.02

`mise ls`

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
`mise-2026.2.8 ls`	22.0 ± 0.7	21.2	31.1	1.00
`mise ls`	22.1 ± 0.4	21.5	23.5	1.00 ± 0.04

`xtasks/test/perf`

Command	mise-2026.2.8	mise	Variance
install (cached)	124ms	125ms	+0%
ls (cached)	77ms	77ms	+0%
bin-paths (cached)	81ms	81ms	+0%
task-ls (cached)	555ms	555ms	+0%

- Strip 'v' prefix from version before reconstructing URL with explicit 'v' prefix, ensuring correct download URL regardless of whether status.version() includes the prefix - Make update_mise_shim async and await the download instead of using block_in_place, since run() is already async Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

cursor

Cursor Bugbot has reviewed your changes and found 2 potential issues.

^{Bugbot Autofix is ON, but a Cloud Agent failed to start.}

src/cli/self_update.rs

cursor · 2026-02-09T22:57:39Z

src/cli/self_update.rs

+
+        let temp_dir = tempfile::tempdir()?;
+        let zip_path = temp_dir.path().join("mise.zip");
+        HTTP.download_file(&url, &zip_path, None).await?;


Release archive downloaded twice during Windows self-update

Low Severity

update_mise_shim re-downloads the entire release zip archive that was already downloaded and processed by the self_update library in do_update_blocking. On Windows, every mise self-update invocation downloads the same (potentially large) archive twice — once for mise.exe and once for mise-shim.exe.

Addresses PR review feedback: - Verify the downloaded zip archive signature using zipsign before extracting mise-shim.exe, matching the verification done for mise.exe - Use atomic write (temp file + rename) to avoid leaving a partially written mise-shim.exe if the process is interrupted - Name the temp zip with the real archive name so zipsign signing context matches Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

@jdx

### 🚀 Features - auto-select no-YJIT Ruby on older glibc systems by @jdx in [#8069](#8069) ### 🐛 Bug Fixes - **(shim)** update mise-shim.exe during self-update on Windows by @jdx in [#8075](#8075) - Bump xx to 2.5 by @erickt in [#8077](#8077) ### 📚 Documentation - **(ruby)** remove experimental language for precompiled binaries by @jdx in [#8073](#8073) ### New Contributors - @erickt made their first contribution in [#8077](#8077) ## 📦 Aqua Registry Updates #### Updated Packages (1) - [`carthage-software/mago`](https://github.com/carthage-software/mago)

## Summary - After `mise self-update` updates `mise.exe` on Windows, also extract and update `mise-shim.exe` from the same release archive - Non-fatal: if the shim update fails, a warning is emitted but the overall self-update still succeeds - Uses existing `zip`, `tempfile`, and `HTTP` client — no new dependencies Fixes the issue where `mise self-update` only updated `mise.exe` but left `mise-shim.exe` at the old version, requiring users to manually download it from GitHub releases. Reported after jdx#8045 added native `.exe` shim mode. ## Test plan - [ ] Verify `cargo clippy --workspace` passes (confirmed locally) - [ ] Test on Windows: `mise self-update --force` updates both `mise.exe` and `mise-shim.exe` - [ ] Test on Windows: if `mise-shim.exe` is missing from the archive, a warning is printed but the update succeeds - [ ] Verify non-Windows builds are unaffected (all new code is `#[cfg(windows)]`) 🤖 Generated with [Claude Code](https://claude.com/claude-code)  --- > [!NOTE] > **Medium Risk** > Touches the Windows self-update path and adds new download/extract/replace logic for an executable; failures are non-fatal but a bug could leave the shim outdated or not replaced as expected. > > **Overview** > On Windows, `mise self-update` now also updates `mise-shim.exe` after updating `mise.exe` by downloading the matching release `.zip`, verifying its `zipsign` signature, extracting `mise/bin/mise-shim.exe`, and atomically replacing the local shim (non-fatal on failure). > > This adds a Windows-only dependency on `zipsign-api` and updates `Cargo.lock` accordingly, plus a small tweak to version styling output to reuse the string value. > > <sup>Written by [Cursor Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit 7267f26. This will update automatically on new commits. Configure [here](https://cursor.com/dashboard?tab=bugbot).</sup>  --------- Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

@jdx

### 🚀 Features - auto-select no-YJIT Ruby on older glibc systems by @jdx in [jdx#8069](jdx#8069) ### 🐛 Bug Fixes - **(shim)** update mise-shim.exe during self-update on Windows by @jdx in [jdx#8075](jdx#8075) - Bump xx to 2.5 by @erickt in [jdx#8077](jdx#8077) ### 📚 Documentation - **(ruby)** remove experimental language for precompiled binaries by @jdx in [jdx#8073](jdx#8073) ### New Contributors - @erickt made their first contribution in [jdx#8077](jdx#8077) ## 📦 Aqua Registry Updates #### Updated Packages (1) - [`carthage-software/mago`](https://github.com/carthage-software/mago)

It's now using mise-shim.exe jdx/mise#8075

Copilot AI review requested due to automatic review settings February 9, 2026 21:33

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jdx merged commit a6fbdc8 into main Feb 10, 2026
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jdx deleted the fix/self-update-mise-shim branch February 10, 2026 02:14

mise-en-dev mentioned this pull request Feb 10, 2026

chore: release 2026.2.9 #8074

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BrewTestBot mentioned this pull request Feb 10, 2026

mise 2026.2.9 Homebrew/homebrew-core#266756

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jc00ke added a commit to jc00ke/dotfiles that referenced this pull request Feb 19, 2026

mise: use default shim mode on Windows

3db0e8e

It's now using mise-shim.exe jdx/mise#8075

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fix(shim): update mise-shim.exe during self-update on Windows#8075

fix(shim): update mise-shim.exe during self-update on Windows#8075
jdx merged 3 commits intomainfrom
fix/self-update-mise-shim

jdx commented Feb 9, 2026 •

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-        tokio::task::block_in_place(|| {
-            tokio::runtime::Handle::current().block_on(HTTP.download_file(&url, &zip_path, None))
-        })?;
+        if let Ok(handle) = tokio::runtime::Handle::try_current() {
+            handle.block_on(HTTP.download_file(&url, &zip_path, None))?;
+        } else {
+            let rt = tokio::runtime::Runtime::new()?;
+            rt.block_on(HTTP.download_file(&url, &zip_path, None))?;
+        }

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Release archive downloaded twice during Windows self-update

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jdx commented Feb 9, 2026 •

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`mise x -- echo`

`mise env`

`mise hook-env`

`mise ls`

`xtasks/test/perf`