5 files changed, 31 insertions(+), 12 deletions(-)

M .gitignore
M CHANGELOG.md
M VERSION
M bin/gstack-telemetry-log
M test/telemetry.test.ts

@@ 15,3 15,4 @@ bun.lock
 .env.local
 .env.*
 !.env.example
+supabase/.temp/

@@ 1,5 1,12 @@
 # Changelog
 
+## [0.11.16.1] - 2026-03-24 — Installation ID Privacy Fix
+
+### Fixed
+
+- **Installation IDs are now random UUIDs instead of hostname hashes.** The old `SHA-256(hostname+username)` approach meant anyone who knew your machine identity could compute your installation ID. Now uses a random UUID stored in `~/.gstack/installation-id` — not derivable from any public input, rotatable by deleting the file.
+- **RLS verification script handles edge cases.** `verify-rls.sh` now correctly treats INSERT success as expected (kept for old client compat), handles 409 conflicts and 204 no-ops.
+
 ## [0.11.16.0] - 2026-03-24 — Telemetry Security Hardening
 
 ### Fixed

@@ 1,1 1,1 @@
-0.11.16.0
+0.11.16.1

@@ 106,18 106,29 @@ if [ -d "$STATE_DIR/sessions" ]; then
 fi
 
 # Generate installation_id for community tier
+# Uses a random UUID stored locally — not derived from hostname/user so it
+# can't be guessed or correlated by someone who knows your machine identity.
 INSTALL_ID=""
 if [ "$TIER" = "community" ]; then
-  HOST="$(hostname 2>/dev/null || echo "unknown")"
-  USER="$(whoami 2>/dev/null || echo "unknown")"
-  if command -v shasum >/dev/null 2>&1; then
-    INSTALL_ID="$(printf '%s-%s' "$HOST" "$USER" | shasum -a 256 | awk '{print $1}')"
-  elif command -v sha256sum >/dev/null 2>&1; then
-    INSTALL_ID="$(printf '%s-%s' "$HOST" "$USER" | sha256sum | awk '{print $1}')"
-  elif command -v openssl >/dev/null 2>&1; then
-    INSTALL_ID="$(printf '%s-%s' "$HOST" "$USER" | openssl dgst -sha256 | awk '{print $NF}')"
+  ID_FILE="$HOME/.gstack/installation-id"
+  if [ -f "$ID_FILE" ]; then
+    INSTALL_ID="$(cat "$ID_FILE" 2>/dev/null)"
+  fi
+  if [ -z "$INSTALL_ID" ]; then
+    # Generate a random UUID v4
+    if command -v uuidgen >/dev/null 2>&1; then
+      INSTALL_ID="$(uuidgen | tr '[:upper:]' '[:lower:]')"
+    elif [ -r /proc/sys/kernel/random/uuid ]; then
+      INSTALL_ID="$(cat /proc/sys/kernel/random/uuid)"
+    else
+      # Fallback: random hex from /dev/urandom
+      INSTALL_ID="$(od -An -tx1 -N16 /dev/urandom 2>/dev/null | tr -d ' \n')"
+    fi
+    if [ -n "$INSTALL_ID" ]; then
+      mkdir -p "$(dirname "$ID_FILE")" 2>/dev/null
+      printf '%s' "$INSTALL_ID" > "$ID_FILE" 2>/dev/null
+    fi
   fi
-  # If no SHA-256 command available, install_id stays empty
 fi
 
 # Local-only fields (never sent remotely)

@@ 78,8 78,8 @@ describe('gstack-telemetry-log', () => {
 
     const events = parseJsonl();
     expect(events).toHaveLength(1);
-    // installation_id should be a SHA-256 hash (64 hex chars)
-    expect(events[0].installation_id).toMatch(/^[a-f0-9]{64}$/);
+    // installation_id should be a UUID v4 (or hex fallback)
+    expect(events[0].installation_id).toMatch(/^[a-f0-9-]{32,36}$/);
   });
 
   test('installation_id is null for anonymous tier', () => {