[mweinbach]

Problem

On Windows, installing the managed Codex runtime can fail in three ways:

• CodexInstallation runs bare tar. That can resolve to Git's MSYS2 usr/bin/tar.exe, which reads C:\... archive paths as a remote hostname:file spec.
• tar -tzf / tar -tvzf output is split only on \n, so CRLF output leaves \r on every entry.
• fs.rename(staging, destination) runs right after the codex.exe --version check exits. Defender or process rundown can still hold the exe for a moment, so the rename fails with EPERM/EACCES.

When an install is interrupted, its .install-* / .active-* staging directories stay behind. They also make an otherwise empty managed runtime look removable.

Change

• Run all tar calls through cliArchiveTarCommand(platform, environment), which resolves to %SystemRoot%\System32\tar.exe on Windows and tar elsewhere.
• Split tar output on /\r?\n/u.
• On win32, retry the staging → destination rename up to 10 times, 100 ms apart.
• At startup, remove .install-* / .active-* staging directories only when they are at least 24 hours old. Keep the managed root and derive canRemove from its remaining contents; an unreadable root remains removable.

Scope and approval

Split from #18508 to follow the one-problem rule in CONTRIBUTING.md. This PR touches CodexInstallation.ts and its focused test file. The updater, ACP registry, and other performance fixes are separate replacement PRs.

Verification

• The tar command comes from the existing shared cliArchiveTarCommand helper, which the CLI release path already uses for the same MSYS tar problem.
• The rename retry is limited to win32, so other platforms behave exactly as before.
• The startup sweep only removes entries with the installer's own temp-dir prefixes (.install-, .active-). It runs before canRemove is computed.
• Maintenance verification on macOS ARM64 / Node 24.21.0: vp test run src/provider/CodexInstallation.test.ts from apps/server — 27 passed. The simulated Windows test checks System32 tar selection with CRLF listings and three PermissionDenied renames followed by successful installation, advancing TestClock between retries. A non-Windows rename failure remains a failed install. The startup tests cover stale cleanup and retention of recent staging directories.
• Targeted lint and server typecheck pass. A fresh real Windows install was not rerun during this maintenance pass.

Model: Claude 5.5 Opus

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[chatgpt-codex-connector]

Codex Review Summary

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Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-10-13T00:22:17.683099Z	0dac4dd	New commits

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📝 Walkthrough

Walkthrough

Codex installation now selects a platform- and environment-specific tar command, retries runtime-directory renames on Windows, and removes stale staging directories at startup.

Changes

Codex Installation

Layer / File(s)	Summary
Select tar command for archive operations apps/server/src/provider/CodexInstallation.ts, apps/server/src/provider/CodexInstallation.test.ts	Archive listing, type inspection, and extraction use the platform- and environment-selected tar command. Tests provide Windows archive output and a simulated package layout.
Retry Windows runtime-directory rename apps/server/src/provider/CodexInstallation.ts, apps/server/src/provider/CodexInstallation.test.ts	Windows retries runtime-directory renames up to 10 times, with 100 ms spacing. Other platforms attempt the rename once. Tests cover retries on Windows and failure after one attempt on a non-Windows platform.
Remove stale staging directories apps/server/src/provider/CodexInstallation.ts, apps/server/src/provider/CodexInstallation.test.ts	Startup removes staging directories that are at least 24 hours old. It sets canRemove based on whether the managed directory is unreadable or contains entries. Tests cover stale and live staging directories.

Priority: ➖ Normal

Estimated code review effort: 3 (Moderate) | ~20 minutes

Change: Bug fix

Suggested reviewers: juliusmarminge

Merge Risk: ⚪ Minimal · up to c673a

The changes target Windows extraction and rename failures and clean up stale staging directories. The supplied evidence covers these paths and identifies no unresolved concrete failure that blocks merging.

Security Architecture Review

Security architecture risk: 🔵 Low · up to c673a

Windows extraction and activation retain their validation controls. The main residual risk is that age-based cleanup can interrupt another server's unusually long-running or suspended installation when both share the same runtime directory.

Retained concerns

• Low · reliability · inferred: Startup treats matching staging entries at least 24 hours old as abandoned without checking whether another server still owns them. Because nested writes do not refresh the staging directory's mtime and tar operations have no local deadline, a stalled or suspended installation can lose its working state when another server starts against the same base directory. This newly introduced cross-instance interference can fail installation or pointer publication; the sweep does not select completed releases or the existing active pointer.

Security review details

Security Blast Radius

• inferred — The identified cleanup interference is scoped to server instances sharing the configured tools/codex directory. The inspected production construction path does not add request-controlled filesystem roots or release assets. No new cross-service authority or privilege grant is established by these changes.

Trust Boundaries and Controls

• observed — Tar selection uses the host environment rather than new request input. With the normal Windows root values, it names an explicit System32 executable, whose .exe spawn path uses shell=false. Non-Windows PATH-based tar selection and caller-supplied factory overrides predate this PR.

Resilience and Maintainability Implications

• observed — Startup cleanup selects only immediate installer-prefixed entries, skips missing metadata, preserves entries younger than 24 hours, ignores removal failures and retains the managed root. Completed version directories and active.json are not selected. These limits contain the ownership concern but do not prove that aged staging is abandoned.

Hardening Proposals

• proposed — For shared-directory operation, make staging reclamation ownership-aware, for example through a cross-instance lease with explicit abandoned-owner recovery, instead of using directory age as the sole abandonment signal.

Pre-merge checks | 4

✅ Passed checks (4 passed)

Check name	Status	Explanation
Linked Issues check		Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check		Check skipped because no linked issues were found for this pull request.
Title check		The title clearly and concisely describes the main Windows Codex installation fixes: using system tar and retrying the rename.
Description check		The description includes Problem, Change, Scope and approval, and Verification sections. It explains the Windows failures, implementation, scope, focused tests, observed results, limitations, and the …

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Inline comments:
Review comments at @apps/server/src/provider/CodexInstallation.ts:
- Line 718: Update the cleanup flow around the second readDirectory call so a
read failure skips removal of managedDirectory; remove it only when a successful
read confirms the directory is empty.

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[chatgpt-codex-connector]

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[juliusmarminge]

Note

This comment is posted by Julius' dot

The new cleanup test covers stale staging directories, but the Windows extraction and rename-retry changes still have no reported behavioral results. Please add focused tests with simulated Windows command output and rename failures, or document the Windows checks you performed and their results, under the verification rule. This can return to ready once that evidence is attached.

[chatgpt-codex-connector]

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[mweinbach]

Added focused tests in d31448f (CodexInstallation.test.ts):

• Windows install: win32 platform with a fake ChildProcessSpawner that stands in for bsdtar. The -tzf / -tvzf listings are CRLF-terminated and extraction writes the Windows layout (codex.exe etc.). The first three runtime renames fail with PermissionDenied. The test asserts that every tar call goes to C:\Windows\System32\tar.exe, that the install succeeds after the retries, and that it resolves to bin/codex.exe.
• Other platforms: a single failed runtime rename on darwin fails the install, so the retry stays Windows-only.
• Startup sweep: stale .install-* / .active-* directories are removed and a recent one is kept. This test now reads the clock through Clock, which fixes the Typecheck failure.

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[AdEx-Partners-DE]

One finding from running this on a real Windows host (Windows 11 Pro, Node 24.13); we adopted the change into a fork today.

The new test "installs on Windows via System32 tar with CRLF output and a locked runtime" fails here, but only at its last assertion, and only because of the path separator:

Expected: "C:\Users\...\Temp\t3-codex-install-test-iE9288/tools/codex/0.156.1/bin/codex.exe"
Received: "C:\Users\...\Temp\t3-codex-install-test-iE9288\tools\codex\0.156.1\bin\codex.exe"
 ❯ src/provider/CodexInstallation.test.ts:485

Everything before it passes, including the check that C:\Windows\System32\tar.exe is what gets called. The expected value is built as `${h.baseDir}/tools/codex/0.156.1/bin/codex.exe`, and on Windows the resolved path comes back with backslashes. Comparing both sides with the separators normalized makes it pass here:

expect((yield* h.installation.resolve()).executablePath.replaceAll("\\", "/")).toBe(
  `${h.baseDir.replaceAll("\\", "/")}/tools/codex/0.156.1/bin/codex.exe`,
);

For context: on this machine 21 other tests in CodexInstallation.test.ts already fail before your change, and the same 21 after it; I did not look into those here. tsc --noEmit in apps/server is clean.

Not checked: a real Codex install through the app with a locked runtime; I only ran the test file.

Posted by Claude (Opus 5.5, Claude Code via T3 Code) on behalf of @AdEx-Partners-DE.

[mweinbach]

@AdEx-Partners-DE thanks for running it on a real Windows host. Fixed in f05a2a2: the expected path is now built with path.join(h.baseDir, "tools", "codex", "0.156.1", "bin", "codex.exe"), so the separators match on every OS. The other 21 failures you saw are already there on main and are outside this PR.

[chatgpt-codex-connector]

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[AdEx-Partners-DE]

Confirmed on the same Windows host: with 567b3c2ff the test "installs on Windows via System32 tar with CRLF output and a locked runtime" passes here (1 passed when run alone), and the rest of the file still shows 21 failing tests here, the same count as before your change. We dropped our local workaround and took your version. Thanks for the quick fix.

Posted by Claude (Opus 5.5, Claude Code via T3 Code) on behalf of @AdEx-Partners-DE.