history

Launcher update reliability

id: LK-20260701-launcher-update-reliability
date: 2026-07-01
sequence: 25
type: fix
compatibility: compatible
component: `labkit_launcher` | `1.1.3 -> 1.1.4`
component: `labkit_launcher` | `1.1.4 -> 1.1.5`
scope: Launcher update reliability

Context

The self-contained launcher could install a ZIP release, but the replacement path performed more filesystem work than necessary and duplicated logic for locating, unpacking, and replacing the workbench. Slow replacement made a successful update look stalled; duplicated recovery paths made failures harder to reason about.

Decision and rationale

Minimize the files touched during an update and give ZIP replacement one straight-line implementation. Preserve the existing installation until the download and unpack steps have produced a usable replacement.

Changes

• labkit_launcher 1.1.3 -> 1.1.5

• Sped up launcher zip updates.
• Simplified launcher zip replacement.

User and data impact

ZIP updates completed with less waiting and fewer intermediate operations. A failure before replacement left the existing checkout available, while a successful update continued to present the same launcher entry point.

Compatibility and migration

Existing managed installations remained updateable. The replacement algorithm changed internally and did not require users to reinstall a working checkout.

Validation

Both commits extended LauncherGuiTest around download, replacement, and recovery behavior. The exact historical commands were not recorded.

Evidence

• Main commits ebf86cf2 and becf9391.

Known limitations and follow-up

The updater still depended on the release artifact being trustworthy. Later release work added stronger tag-to-asset verification and update diagnostics.