[StivenKN]

State of a Linux host after updating its background service from the app, from A to B:

	Before	After
readlink ~/.local/bin/t3	runtime/versions/<A>/t3	runtime/versions/<B>/t3
t3 doctor (added after A)	Unknown command "doctor"	runs
Runtime A on disk	kept forever (launcher pins it)	pruned once unused

Updating a server from the app moved the background service to the new version but left the t3 command on PATH behind. Only t3 update repoints the launcher, and the runtime prune keeps any version a launcher points at, so the CLI stayed old indefinitely and newer commands like t3 doctor failed. Fixes #25724.

When a boot-service server starts, it now moves t3 launchers that link straight into an older runtime of its own T3 home to the version it runs, then prunes as before. It waits until the service launcher commits the update, so an update that rolls back leaves the launcher alone. It only moves launchers forward, only to an installed runtime, and never touches launchers for another install or plain copies of the executable. t3 update now uses the same launcher writer.

Proved with focused tests in selfUpdate.test.ts that fail without the fix: a launcher on an older runtime moves to the service's version and the old runtime is pruned, a launcher waits for a trial update to commit, and a launcher on a newer runtime is left alone. vp test run src/cloud/ src/cli/update.test.ts src/serverRuntimeStartup.test.ts passes 180/180, and typecheck and lint are clean.

Reviewed with opus-loop: 2 rounds with Claude Opus 5.5. Opus 5.5 verdict: approved

Created with Claude Opus 5.5 in Claude Code, running in T3 Code.

🤖 Generated with Claude Code

[macroscopeapp]

Approvability

Verdict: Needs Human Approval

Macroscope's review found this PR requires human approval — This change makes managed-service updates automatically repoint the host's t3 launcher, adding cross-platform filesystem mutation and commit-synchronized startup behavior. The behavior spans the service lifecycle and CLI runtime management rather than remaining a small isolated fix.

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[coderabbitai]

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• File: .coderabbit.config.ts
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Reviewing files that changed from the base of the PR and between 76c1dd7 and 3a6205e.

Files selected for processing: 1

• docs/user/updating.md

Files skipped from review as they are similar to previous changes: 1

• docs/user/updating.md

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Walkthrough

Startup pruning waits for service commitment before advancing eligible shell launchers to the running version. The update flow then prunes runtimes. CLI launcher rewriting uses the shared launcher-writing helper.

Changes: Runtime launcher update

Layer / File(s)	Summary
Discover and advance shell launchers apps/server/src/cloud/pinnedRuntime.ts, apps/server/src/cli/update.ts	Launcher discovery retains launcher paths with their targets. Shared helpers write launchers and advance eligible launchers to an installed, newer runtime. The CLI update path uses the shared writer.
Gate startup pruning on commitment apps/server/src/cloud/serviceLauncherClient.ts, apps/server/src/cloud/selfUpdate.ts, apps/server/src/cloud/selfUpdate.test.ts, apps/server/src/cloud/serviceLauncherClient.test.ts, docs/user/updating.md	The launcher client exposes a completion effect for service commitment. Startup pruning waits for that effect before advancing launchers and pruning runtimes. Tests cover older, trial, and newer launcher targets. The update documentation describes supported remote service updates.

Priority: Normal

Estimated code review effort: 3 (Moderate) | ~25 minutes

Change: Bug fix · Severity of issue fixed: Medium

Sequence Diagram(s)

sequenceDiagram
  participant ServiceLauncher
  participant ServiceLauncherClient
  participant pruneRuntimesOnStart
  participant advanceShellLaunchers
  participant ShellLauncher
  ServiceLauncher->>ServiceLauncherClient: matching committed reply
  pruneRuntimesOnStart->>ServiceLauncherClient: await committed
  pruneRuntimesOnStart->>advanceShellLaunchers: advance to running version
  advanceShellLaunchers->>ShellLauncher: replace eligible launcher target

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Possibly related issues

• pingdotgg/t3code#25398: The issue concerns old runtimes retained because launcher paths reference them. This change advances eligible symlink launchers, but does not change a runtime entry binary found on the service PATH.
• pingdotgg/t3code#17532: The issue concerns stale runtime selection from a service PATH after self-update. The supplied summary says this scenario remains unaddressed.

Merge Risk: Minimal · up to 3a620

No actionable issue remains in the supplied review scope; this change is mergeable after normal checks.

Pre-merge checks: 4

Check name	Status	Explanation
Title check		The title clearly and concisely describes the main change: moving the t3 command to the new server version during app updates.
Description check		The description covers the problem, expected behavior, implementation, scope, linked issue, focused verification results, and agent details. It explains the launcher and pruning behavior clearly.
Linked Issues check		Directly linked issue #25724 asks that an in-app server update not leave the t3 PATH launcher on an older runtime. The requested outcome is either a launcher fix or a user instruction to run `t3 upd…
Out of Scope Changes check		All changed areas connect to #25724: - pinnedRuntime.ts: writeShellLauncher and advanceShellLaunchers, with ownership and version guards. These implement the launcher advance. - selfUpdate.ts: `pr…

Full details: Linked Issues check

Explanation

Directly linked issue #25724 asks that an in-app server update not leave the t3 PATH launcher on an older runtime. The requested outcome is either a launcher fix or a user instruction to run t3 update <version>. The PR takes the launcher-fix path.

Implementation per the whole-PR summary:

• pruneRuntimesOnStart (apps/server/src/cloud/selfUpdate.ts) runs at boot-service start. When the launcher is managed, it waits for ServiceLauncherClient.committed (serviceLauncherClient.ts). A rolled-back trial therefore leaves launchers alone.
• advanceShellLaunchers (apps/server/src/cloud/pinnedRuntime.ts) checks that the running runtime is installed. It then moves only t3 launchers that resolve into the same T3 home and point at an exact, older version. Newer, invalid-version, unrelated, and unresolved targets are skipped.
• Runtime pruning runs after the launcher update, so the old runtime is no longer pinned and can be removed. This matches the issue's expected outcome.
• writeShellLauncher is shared by t3 update (apps/server/src/cli/update.ts), which keeps one launcher-writing path.

Tests: selfUpdate.test.ts adds tests for moving an older launcher and pruning its runtime, waiting for a trial commit, and leaving a newer launcher unchanged. The reported focused run passes 180/180.

Uncertainty: the incremental diff from the previous reviewed head (76c1dd7) to head (3a6205e) could not be read because changed blobs are missing from the checkout. The full pinnedRuntime.ts read was truncated before advanceShellLaunchers. This verdict relies on the whole-PR summary for that function and on the prior assessment. The summary describes the current state, so it is accepted as evidence.

The issue scope is Linux systemd boot-service hosts. The non-managed path is not changed, which is consistent with that scope.

Full details: Out of Scope Changes check

Explanation

All changed areas connect to #25724:

• pinnedRuntime.ts: writeShellLauncher and advanceShellLaunchers, with ownership and version guards. These implement the launcher advance.
• selfUpdate.ts: pruneRuntimesOnStart now takes launcher management and commit state. It advances launchers before pruning. This is the startup integration.
• serviceLauncherClient.ts and its test: the committed effect. It gates the launcher update on a committed service update.
• cli/update.ts: repointLauncher uses the shared writeShellLauncher. The PR description states this shared path is intended. Existing t3 update error messages and target checks are retained according to the summary.
• selfUpdate.test.ts: focused tests for the new behavior.
• docs/user/updating.md: wording now states that supported background services and the install-script t3 command update remotely. This describes the new behavior and sits inside the issue's documentation scope.

No unrelated behavior change is shown. The incremental diff from 76c1dd7 could not be read, so this verdict relies on the whole-PR summary.

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[coderabbitai]

Actionable comments posted: 1

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• 🪄 Fix comments: Fix CodeRabbit comments on this PR

Prompt to fix review comments

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Inline comments:
Review comments at @docs/user/updating.md:
- Line 80: Update the “Update server” table entry to clarify that the
background-service update also moves the T3 Code-managed `t3` launcher for the
same runtime home to the new version; do not imply that other `t3` copies on the
host are updated.

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• Source mode: Auto
• Repository: pingdotgg/t3code
• Branch: main
• File: .coderabbit.config.ts
• Commit: 71ba6b3
• Layers: Repository TS config
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Commits

Reviewing files that changed from the base of the PR and between 71ba6b3 and 76c1dd7.

Files selected for processing: 7

• apps/server/src/cli/update.ts
• apps/server/src/cloud/pinnedRuntime.ts
• apps/server/src/cloud/selfUpdate.test.ts
• apps/server/src/cloud/selfUpdate.ts
• apps/server/src/cloud/serviceLauncherClient.test.ts
• apps/server/src/cloud/serviceLauncherClient.ts
• docs/user/updating.md

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