The material below is a bundle of source-file excerpts, with each original file and line range labeled.
SKILL.md is the entry point; the labeled ranges identify which excerpts are supplied.

--- BEGIN FILE "gstack-upgrade/SKILL.md" (lines 31-366; entrypoint) ---
## Inline upgrade flow

This section is referenced by all skill preambles when they detect `UPGRADE_AVAILABLE`.

### Step 1: Ask the user (or auto-upgrade)

First, check if auto-upgrade is enabled:
```bash
_AUTO=""
[ "${GSTACK_AUTO_UPGRADE:-}" = "1" ] && _AUTO="true"
[ -z "$_AUTO" ] && _AUTO=$(~/.claude/skills/gstack/bin/gstack-config get auto_upgrade 2>/dev/null || true)
echo "AUTO_UPGRADE=$_AUTO"
```

**If `AUTO_UPGRADE=true` or `AUTO_UPGRADE=1`:** Skip AskUserQuestion. Log "Auto-upgrading gstack v{old} → v{new}..." and proceed directly to Step 2. On setup failure, follow Step 4's install-specific recovery: vendored installs restore their backup; git installs stop with the pre-upgrade commit recorded, without a destructive reset. Never claim restoration unless it actually succeeded.

**Otherwise**, use AskUserQuestion:
- Question: "gstack **v{new}** is available (you're on v{old}). Upgrade now?"
- Options: ["Yes, upgrade now", "Always keep me up to date", "Not now", "Never ask again"]

**If "Yes, upgrade now":** Proceed to Step 2.

**If "Always keep me up to date":**
```bash
~/.claude/skills/gstack/bin/gstack-config set auto_upgrade true
```
Tell user: "Auto-upgrade enabled. Future updates will install automatically." Then proceed to Step 2.

**If "Not now":** Write snooze state with escalating backoff (first snooze = 24h, second = 48h, third+ = 1 week), then continue with the current skill. Do not mention the upgrade again.
```bash
GSTACK_STATE_ROOT=$(~/.claude/skills/gstack/bin/gstack-paths --get GSTACK_STATE_ROOT); : "${GSTACK_STATE_ROOT:?gstack-paths failed; reinstall with ./setup or /gstack-upgrade}"
_SNOOZE_FILE="$GSTACK_STATE_ROOT/update-snoozed"
_REMOTE_VER="{new}"
_CUR_LEVEL=0
if [ -f "$_SNOOZE_FILE" ]; then
  _SNOOZED_VER=$(awk '{print $(1)}' "$_SNOOZE_FILE")
  if [ "$_SNOOZED_VER" = "$_REMOTE_VER" ]; then
    _CUR_LEVEL=$(awk '{print $(2)}' "$_SNOOZE_FILE")
    case "$_CUR_LEVEL" in *[!0-9]*) _CUR_LEVEL=0 ;; esac
  fi
fi
_NEW_LEVEL=$((_CUR_LEVEL + 1))
[ "$_NEW_LEVEL" -gt 3 ] && _NEW_LEVEL=3
echo "$_REMOTE_VER $_NEW_LEVEL $(date +%s)" > "$_SNOOZE_FILE"
```
Note: `{new}` is the remote version from the `UPGRADE_AVAILABLE` output — substitute it from the update check result.

Tell user the snooze duration: "Next reminder in 24h" (or 48h or 1 week, depending on level). Tip: "Set `auto_upgrade: true` in `~/.gstack/config.yaml` for automatic upgrades."

**If "Never ask again":**
```bash
~/.claude/skills/gstack/bin/gstack-config set update_check false
```
Tell user: "Update checks disabled. Run `~/.claude/skills/gstack/bin/gstack-config set update_check true` to re-enable."
Continue with the current skill.

### Step 2: Detect install type

Figure out how gstack was installed and where.

### Step 3: Save old version

Run this after Step 4 has finished so the recorded version matches what is installed:

```bash
OLD_VERSION=$(cat "$INSTALL_DIR/VERSION" 2>/dev/null || echo "unknown")
echo "OLD_VERSION=$OLD_VERSION"
```

### Step 4: Upgrade

Upgrade gstack with whatever method fits the install. If something goes wrong, put it back the way it was.

### Step 4.75: Run version migrations

After `./setup` completes, run any migration scripts for versions between the old
and new version. Migrations handle state fixes that `./setup` alone can't cover
(stale config, orphaned files, directory structure changes).

```bash
MIGRATIONS_DIR="$INSTALL_DIR/gstack-upgrade/migrations"
if [ -d "$MIGRATIONS_DIR" ]; then
  for migration in $(find "$MIGRATIONS_DIR" -maxdepth 1 -name 'v*.sh' -type f 2>/dev/null | sort -V); do
    # Extract version from filename: v0.15.2.0.sh → 0.15.2.0
    m_ver="$(basename "$migration" .sh | sed 's/^v//')"
    # Run if this migration version is newer than old version
    # (simple string compare works for dotted versions with same segment count)
    if [ "$OLD_VERSION" != "unknown" ] && [ "$(printf '%s\n%s' "$OLD_VERSION" "$m_ver" | sort -V | head -1)" = "$OLD_VERSION" ] && [ "$OLD_VERSION" != "$m_ver" ]; then
      echo "Running migration $m_ver..."
      # GSTACK_INSTALL_DIR: migrations that clean the INSTALL (not just
      # ~/.gstack state) default to ~/.claude/skills/gstack when unset —
      # a repo-local install would silently no-op without this.
      GSTACK_INSTALL_DIR="$INSTALL_DIR" bash "$migration" || echo "  Warning: migration $m_ver had errors (non-fatal)"
    fi
  done
fi
```

Migrations are idempotent bash scripts in `gstack-upgrade/migrations/`. Each is named
`v{VERSION}.sh` and runs only when upgrading from an older version. See CONTRIBUTING.md
for how to add new migrations.

### Step 5: Write marker + clear cache

```bash
GSTACK_STATE_ROOT=$(~/.claude/skills/gstack/bin/gstack-paths --get GSTACK_STATE_ROOT); : "${GSTACK_STATE_ROOT:?gstack-paths failed; reinstall with ./setup or /gstack-upgrade}"
mkdir -p "$GSTACK_STATE_ROOT"
echo "$OLD_VERSION" > "$GSTACK_STATE_ROOT"/just-upgraded-from
rm -f "$GSTACK_STATE_ROOT"/last-update-check
rm -f "$GSTACK_STATE_ROOT"/update-snoozed
```

### Step 6: Show What's New

Read `$INSTALL_DIR/CHANGELOG.md`. Find all version entries between the old version and the new version. Summarize as 5-7 bullets grouped by theme. Don't overwhelm — focus on user-facing changes. Skip internal refactors unless they're significant.

Format:
```
gstack v{new} — upgraded from v{old}!

What's new:
- [bullet 1]
- [bullet 2]
- ...

Happy shipping!
```

### Step 7: Continue

After showing What's New, continue with whatever skill the user originally invoked. The upgrade is done — no further action needed.

---


--- END FILE "gstack-upgrade/SKILL.md" ---