diff --git a/CHANGELOG.md b/CHANGELOG.md
index 30f0a4d..ae6ce99 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,8 @@ Versioning.
 - Align the desktop-server device class with macos-ubuntu-bootstrap: Docker
   may be none, rootful, or rootless. The bootstrap orchestrator forwards the
   declared docker_mode and server-baseline hardening flags.
+- Keep `append_hardening_flags` `set -e` safe when ssh/ufw/fail2ban are unset,
+  so desktop-server apply does not exit before phase 0.
 
 ## [0.9.2] - 2026-09-12
 
diff --git a/scripts/bootstrap-device.sh b/scripts/bootstrap-device.sh
index 18764ca..376c0a1 100755
--- a/scripts/bootstrap-device.sh
+++ b/scripts/bootstrap-device.sh
@@ -283,9 +283,9 @@ append_hardening_flags() {
   HARDEN_SSH=$(yaml_get "$DEVICE_PATH" "device.class.hardening.ssh" || true)
   HARDEN_UFW=$(yaml_get "$DEVICE_PATH" "device.class.hardening.ufw" || true)
   HARDEN_F2B=$(yaml_get "$DEVICE_PATH" "device.class.hardening.fail2ban" || true)
-  [ "${HARDEN_SSH:-}" = "true" ] && OS_ARGS+=("--harden-ssh")
-  [ "${HARDEN_UFW:-}" = "true" ] && OS_ARGS+=("--enable-ufw")
-  [ "${HARDEN_F2B:-}" = "true" ] && OS_ARGS+=("--with-fail2ban")
+  if [ "${HARDEN_SSH:-}" = "true" ]; then OS_ARGS+=("--harden-ssh"); fi
+  if [ "${HARDEN_UFW:-}" = "true" ]; then OS_ARGS+=("--enable-ufw"); fi
+  if [ "${HARDEN_F2B:-}" = "true" ]; then OS_ARGS+=("--with-fail2ban"); fi
 }
 case "$PROFILE" in
   desktop)
diff --git a/tests/test_bootstrap_device.py b/tests/test_bootstrap_device.py
index e2b424a..4adc171 100644
--- a/tests/test_bootstrap_device.py
+++ b/tests/test_bootstrap_device.py
@@ -53,6 +53,9 @@ def test_orchestrator_forwards_class_docker_mode() -> None:
     assert 'OS_ARGS+=("--docker-mode" "${CLASS_DOCKER:-none}")' in script
     assert 'OS_ARGS+=("--docker-mode" "${CLASS_DOCKER:-rootful}")' in script
     assert "append_hardening_flags" in script
+    # `cmd && append` is not `set -e` safe as the last statement of a case arm.
+    assert 'if [ "${HARDEN_SSH:-}" = "true" ]; then OS_ARGS+=("--harden-ssh"); fi' in script
+    assert '] && OS_ARGS+=("--harden-ssh")' not in script
 
 
 def test_seed_go_verifies_the_physical_toolchain_without_auto_selection() -> None:
@@ -256,6 +259,28 @@ def git(path: Path, *args: str) -> str:
     assert "OS installer present" in result.stdout
     assert git(estate, "status", "--porcelain") == before == ""
 
+    # desktop-server with no hardening must not trip `set -e` on the flag
+    # appender. Phase 2 --plan prints the derived installer argv.
+    device.write_text(
+        "device:\n  id: example-device\n  name: example\n  os: linux\n"
+        "  architecture: x86_64\n  class:\n    profile: desktop-server\n"
+        "    gui: enabled\n    docker_mode: rootful\n"
+        "    execution_policy: interactive-desktop-server\n"
+    )
+    desktop_server = subprocess.run(
+        [str(embedded), "--estate-root", str(estate), "--device",
+         "estate/devices/example.yaml", "--phase", "2", "--plan"],
+        env=env, capture_output=True, text=True,
+    )
+    assert desktop_server.returncode == 0, desktop_server.stdout + desktop_server.stderr
+    assert "--profile desktop-server" in desktop_server.stdout
+    assert "--docker-mode rootful" in desktop_server.stdout
+    device.write_text(
+        "device:\n  id: example-device\n  name: example\n  os: linux\n"
+        "  architecture: x86_64\n  class:\n    profile: desktop-builds\n"
+        "    gui: enabled\n    docker_mode: rootful\n"
+    )
+
     # Source identity comes from the engine, not the consuming estate commit.
     version = subprocess.check_output(
         [str(embedded), "--estate-root", str(estate), "--source-build-version"],