diff --git a/.github/workflows/release-smoke.yml b/.github/workflows/release-smoke.yml
index 5ec66da8a6..1656d4f16f 100644
--- a/.github/workflows/release-smoke.yml
+++ b/.github/workflows/release-smoke.yml
@@ -38,6 +38,65 @@ on:
         type: string
 
 jobs:
+  # The Docker smoke below can never exercise the background-service leg of
+  # onboarding: containers have no service manager, so v2026.824.0 shipped a
+  # service install that crash-looped on a missing shim while every
+  # golden-path check stayed green. Run the same published artifact directly
+  # on the runner VM's systemd and require the installed service to end up
+  # serving.
+  smoke_service:
+    runs-on: ubuntu-latest
+    timeout-minutes: 30
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v7
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v7
+        with:
+          node-version: 24
+
+      - name: Start a user systemd session
+        # The hosted runner has no login session for the runner user, so
+        # `systemctl --user` cannot reach a user manager until lingering
+        # starts one. Export the session address for the steps below.
+        run: |
+          sudo loginctl enable-linger "$(id -un)"
+          uid="$(id -u)"
+          for _ in $(seq 1 30); do
+            [[ -S "/run/user/$uid/bus" ]] && break
+            sleep 1
+          done
+          [[ -S "/run/user/$uid/bus" ]]
+          {
+            echo "XDG_RUNTIME_DIR=/run/user/$uid"
+            echo "DBUS_SESSION_BUS_ADDRESS=unix:path=/run/user/$uid/bus"
+          } >> "$GITHUB_ENV"
+
+      - name: Onboard with the background service
+        env:
+          PAPERCLIPAI_VERSION: ${{ inputs.paperclip_version }}
+          DATA_DIR: ${{ runner.temp }}/service-smoke-data
+          SMOKE_CLEANUP: "false"
+        run: ./scripts/service-onboard-smoke.sh
+
+      - name: Capture service diagnostics
+        if: always()
+        run: |
+          {
+            systemctl --user --no-pager status paperclipai.service || true
+            journalctl --user -u paperclipai.service --no-pager || true
+          } > "$RUNNER_TEMP/paperclipai-service.log" 2>&1
+
+      - name: Upload service diagnostics
+        if: always()
+        uses: actions/upload-artifact@v7
+        with:
+          name: ${{ inputs.artifact_name }}-service
+          path: ${{ runner.temp }}/paperclipai-service.log
+          retention-days: 14
+
   smoke:
     runs-on: ubuntu-latest
     timeout-minutes: 45
diff --git a/package.json b/package.json
index 16132aeaae..2966139626 100644
--- a/package.json
+++ b/package.json
@@ -54,7 +54,7 @@
     "smoke:mcp-fixtures": "node scripts/smoke/mcp-fixture-harness.mjs",
     "smoke:pipelines-tutorial": "./scripts/smoke/pipelines-tutorial-smoke.sh",
     "smoke:terminal-bench-loop-skill": "node scripts/smoke/terminal-bench-loop-skill-smoke.mjs",
-    "test:release-registry": "node --test scripts/verify-release-registry-state.test.mjs scripts/release-package-map.test.mjs scripts/check-release-package-bootstrap.test.mjs scripts/check-no-git-push.test.mjs scripts/release-lib.test.mjs scripts/release-registry-versions.test.mjs scripts/link-plugin-dev-sdk.test.js scripts/acpx-patch-packaging.test.mjs",
+    "test:release-registry": "node --test scripts/verify-release-registry-state.test.mjs scripts/release-package-map.test.mjs scripts/check-release-package-bootstrap.test.mjs scripts/check-no-git-push.test.mjs scripts/release-lib.test.mjs scripts/release-registry-versions.test.mjs scripts/link-plugin-dev-sdk.test.js scripts/acpx-patch-packaging.test.mjs scripts/service-onboard-smoke.test.mjs",
     "storybook-visual:baseline": "node scripts/storybook-visual-baseline.mjs",
     "test:storybook-visual": "node scripts/storybook-visual-baseline.mjs download && node scripts/storybook-visual-baseline.mjs verify && pnpm build-storybook && npx playwright test --config tests/storybook-visual/playwright.config.ts",
     "test:storybook-visual:update": "node scripts/storybook-visual-baseline.mjs download && pnpm build-storybook && npx playwright test --config tests/storybook-visual/playwright.config.ts --update-snapshots && node scripts/storybook-visual-baseline.mjs pack",
diff --git a/scripts/service-onboard-smoke.sh b/scripts/service-onboard-smoke.sh
new file mode 100755
index 0000000000..4b2d5ec9e4
--- /dev/null
+++ b/scripts/service-onboard-smoke.sh
@@ -0,0 +1,100 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+# Prove that `onboard --install-service` on a released artifact leaves a
+# working background service. The Docker onboard smoke can never cover this
+# leg: containers have no service manager, so a release whose service install
+# crash-loops on a missing shim (v2026.824.0) still passes every golden-path
+# check. This script runs the published npm artifact on a real systemd user
+# session and fails unless the installed service itself ends up serving
+# /api/health.
+#
+# Requirements: a Linux host with a user systemd session. In CI that means
+# `loginctl enable-linger` plus XDG_RUNTIME_DIR / DBUS_SESSION_BUS_ADDRESS
+# pointing at /run/user/<uid>; see the smoke_service job in
+# .github/workflows/release-smoke.yml.
+
+PAPERCLIPAI_VERSION="${PAPERCLIPAI_VERSION:-latest}"
+DATA_DIR="${DATA_DIR:-$(mktemp -d "${TMPDIR:-/tmp}/paperclip-service-smoke.XXXXXX")}"
+ONBOARD_TIMEOUT_SECONDS="${ONBOARD_TIMEOUT_SECONDS:-600}"
+SMOKE_READY_TIMEOUT_SECONDS="${SMOKE_READY_TIMEOUT_SECONDS:-420}"
+HEALTH_URL="${HEALTH_URL:-http://127.0.0.1:3100/api/health}"
+SERVICE_NAME="paperclipai.service"
+SHIM_PATH="${PAPERCLIP_SHIM_PATH:-$HOME/.local/bin/paperclipai}"
+# Cleanup defaults to on so a local run does not leave a service behind; CI
+# disables it so the diagnostics step can still inspect the unit.
+SMOKE_CLEANUP="${SMOKE_CLEANUP:-true}"
+SMOKE_FORCE="${SMOKE_FORCE:-false}"
+
+fail() {
+  echo "Service smoke failed: $*" >&2
+  exit 1
+}
+
+diagnostics() {
+  echo "--- systemctl --user status $SERVICE_NAME ---" >&2
+  systemctl --user --no-pager status "$SERVICE_NAME" >&2 || true
+  echo "--- journalctl --user -u $SERVICE_NAME (last 100 lines) ---" >&2
+  journalctl --user -u "$SERVICE_NAME" --no-pager -n 100 >&2 || true
+}
+
+cleanup() {
+  if [[ "$SMOKE_CLEANUP" == "true" ]]; then
+    if [[ -x "$SHIM_PATH" ]]; then
+      "$SHIM_PATH" service uninstall >/dev/null 2>&1 || true
+    fi
+    systemctl --user stop "$SERVICE_NAME" >/dev/null 2>&1 || true
+  fi
+}
+trap cleanup EXIT INT TERM
+
+command -v systemctl >/dev/null 2>&1 || fail "systemctl is not available on this host"
+systemctl --user show-environment >/dev/null 2>&1 \
+  || fail "no user systemd session; enable lingering and export XDG_RUNTIME_DIR first"
+
+# Refuse to smoke over a host that already has a managed install: the
+# assertions below would prove nothing, and cleanup would tear down a real
+# service.
+if [[ "$SMOKE_FORCE" != "true" ]]; then
+  if [[ -e "$SHIM_PATH" ]]; then
+    fail "$SHIM_PATH already exists; set SMOKE_FORCE=true to smoke over it"
+  fi
+  if systemctl --user cat "$SERVICE_NAME" >/dev/null 2>&1; then
+    fail "$SERVICE_NAME is already installed; set SMOKE_FORCE=true to smoke over it"
+  fi
+fi
+
+echo "==> Onboarding paperclipai@$PAPERCLIPAI_VERSION with --install-service"
+echo "    Data dir: $DATA_DIR"
+if ! timeout "$ONBOARD_TIMEOUT_SECONDS" \
+  npx --yes "paperclipai@${PAPERCLIPAI_VERSION}" onboard --yes --install-service --data-dir "$DATA_DIR"; then
+  diagnostics
+  fail "onboard exited non-zero"
+fi
+
+echo "==> Verifying the managed shim"
+if [[ ! -x "$SHIM_PATH" ]]; then
+  diagnostics
+  fail "no executable shim at $SHIM_PATH after onboarding"
+fi
+
+echo "==> Waiting for $SERVICE_NAME to serve $HEALTH_URL"
+for ((i = 1; i <= SMOKE_READY_TIMEOUT_SECONDS; i += 1)); do
+  state="$(systemctl --user is-active "$SERVICE_NAME" 2>/dev/null || true)"
+  if [[ "$state" == "failed" ]]; then
+    diagnostics
+    fail "$SERVICE_NAME entered the failed state"
+  fi
+  if curl -fsS "$HEALTH_URL" >/dev/null 2>&1; then
+    if [[ "$state" != "active" ]]; then
+      diagnostics
+      fail "$HEALTH_URL answers but $SERVICE_NAME is '$state' - something other than the service is serving"
+    fi
+    echo "==> Service smoke passed: $SERVICE_NAME is active and serving $HEALTH_URL"
+    exit 0
+  fi
+  sleep 1
+done
+
+diagnostics
+fail "$HEALTH_URL not ready after ${SMOKE_READY_TIMEOUT_SECONDS}s (unit state: $(systemctl --user is-active "$SERVICE_NAME" 2>/dev/null || echo unknown))"
diff --git a/scripts/service-onboard-smoke.test.mjs b/scripts/service-onboard-smoke.test.mjs
new file mode 100644
index 0000000000..b859cd3f1b
--- /dev/null
+++ b/scripts/service-onboard-smoke.test.mjs
@@ -0,0 +1,52 @@
+import assert from "node:assert/strict";
+import { execFileSync } from "node:child_process";
+import { accessSync, constants, readFileSync } from "node:fs";
+import { join } from "node:path";
+import test from "node:test";
+
+// Pins the wiring that makes the background-service smoke an effective gate.
+// The service leg exists because v2026.824.0 shipped a service install that
+// crash-looped on a missing shim while the Docker smoke stayed green; these
+// assertions keep the job from being silently disconnected or weakened.
+
+const repoRoot = new URL("..", import.meta.url).pathname.replace(/\/$/, "");
+const scriptPath = join(repoRoot, "scripts", "service-onboard-smoke.sh");
+const script = readFileSync(scriptPath, "utf8");
+const smokeWorkflow = readFileSync(join(repoRoot, ".github", "workflows", "release-smoke.yml"), "utf8");
+const releaseWorkflow = readFileSync(join(repoRoot, ".github", "workflows", "release.yml"), "utf8");
+
+test("smoke script is executable and parses", () => {
+  accessSync(scriptPath, constants.X_OK);
+  execFileSync("bash", ["-n", scriptPath]);
+});
+
+test("smoke script keeps its load-bearing assertions", () => {
+  assert.match(script, /^set -euo pipefail$/m);
+  // Onboards the published artifact with the service leg forced on.
+  assert.match(script, /onboard --yes --install-service/);
+  // Fails when the shim never materialized.
+  assert.match(script, /no executable shim at .*after onboarding/);
+  // Fails when the unit dies instead of serving.
+  assert.match(script, /entered the failed state/);
+  // Fails when health answers but the service is not what is serving --
+  // the exact signature of the v2026.824.0 defect.
+  assert.match(script, /something other than the service is serving/);
+  // Refuses to smoke over a real install unless forced.
+  assert.match(script, /SMOKE_FORCE/);
+});
+
+test("release-smoke workflow runs the service leg against the input version", () => {
+  assert.match(smokeWorkflow, /^  smoke_service:$/m);
+  assert.match(smokeWorkflow, /scripts\/service-onboard-smoke\.sh/);
+  const serviceJob = smokeWorkflow.split(/^  smoke:$/m)[0];
+  assert.match(serviceJob, /PAPERCLIPAI_VERSION: \$\{\{ inputs\.paperclip_version \}\}/);
+  // Diagnostics must survive the run: cleanup stays off in CI and the
+  // artifact name cannot collide with the Docker job's upload.
+  assert.match(serviceJob, /SMOKE_CLEANUP: "false"/);
+  assert.match(serviceJob, /\$\{\{ inputs\.artifact_name \}\}-service/);
+});
+
+test("nightly and beta smokes still route through the reusable workflow", () => {
+  const calls = releaseWorkflow.match(/uses: \.\/\.github\/workflows\/release-smoke\.yml/g) ?? [];
+  assert.ok(calls.length >= 2, "smoke_nightly and smoke_beta must call release-smoke.yml so smoke_service gates them");
+});