diff --git a/app/sovran_systemsos_web/static/js/rebuild.js b/app/sovran_systemsos_web/static/js/rebuild.js
index a377d3c..41b7a03 100644
--- a/app/sovran_systemsos_web/static/js/rebuild.js
+++ b/app/sovran_systemsos_web/static/js/rebuild.js
@@ -51,19 +51,26 @@ async function pollRebuildStatus() {
     if (data.running) return;
     _rebuildFinished = true;
     stopRebuildPoll();
-    onRebuildDone(data.result === "success");
+    if (data.result === "reboot_required") {
+      onRebuildDone("reboot_required");
+    } else {
+      onRebuildDone(data.result === "success");
+    }
   } catch (err) {
     if (!_rebuildServerDown) { _rebuildServerDown = true; if ($rebuildStatus) $rebuildStatus.textContent = "Applying changes…"; }
   }
 }
 
-function onRebuildDone(success) {
+function onRebuildDone(result) {
   if ($rebuildSpinner) $rebuildSpinner.classList.remove("spinning");
   if ($rebuildClose) $rebuildClose.disabled = false;
-  if (success) {
+  if (result === true) {
     if ($rebuildStatus) $rebuildStatus.textContent = "✓ Done";
     // Auto-reload the page after a short delay so tiles and toggles reflect the new state
     setTimeout(function() { window.location.reload(); }, 1200);
+  } else if (result === "reboot_required") {
+    if ($rebuildStatus) $rebuildStatus.textContent = "✓ Done — reboot required";
+    if ($rebuildReboot) $rebuildReboot.style.display = "inline-flex";
   } else {
     if ($rebuildStatus) $rebuildStatus.textContent = "✗ Something went wrong";
     if ($rebuildSave) $rebuildSave.style.display = "inline-flex";
diff --git a/app/sovran_systemsos_web/static/js/update.js b/app/sovran_systemsos_web/static/js/update.js
index 2a7ce7f..791e8d2 100644
--- a/app/sovran_systemsos_web/static/js/update.js
+++ b/app/sovran_systemsos_web/static/js/update.js
@@ -111,14 +111,20 @@ async function pollUpdateStatus() {
           if (data.log) appendLog(data.log);
           _updateLogOffset = data.offset;
         }
-        if (data.result === "success") {
+        if (data.result === "reboot_required") {
+          appendLog("[Server restarted — update completed, reboot required.]\n");
+        } else if (data.result === "success") {
           appendLog("[Server restarted — update completed successfully.]\n");
         } else {
           appendLog("[Server restarted — update encountered an error.]\n");
         }
         _updateFinished = true;
         stopUpdatePoll();
-        onUpdateDone(data.result === "success");
+        if (data.result === "reboot_required") {
+          onUpdateDone("reboot_required");
+        } else {
+          onUpdateDone(data.result === "success");
+        }
         return;
       }
       appendLog("[Server reconnected]\n");
@@ -129,19 +135,27 @@ async function pollUpdateStatus() {
     if (data.running) return;
     _updateFinished = true;
     stopUpdatePoll();
-    if (data.result === "success") onUpdateDone(true);
-    else onUpdateDone(false);
+    if (data.result === "reboot_required") {
+      onUpdateDone("reboot_required");
+    } else if (data.result === "success") {
+      onUpdateDone(true);
+    } else {
+      onUpdateDone(false);
+    }
   } catch (err) {
     if (!_serverWasDown) { _serverWasDown = true; appendLog("\n[Server restarting — waiting for it to come back…]\n"); if ($modalStatus) $modalStatus.textContent = "Server restarting…"; }
   }
 }
 
-function onUpdateDone(success) {
+function onUpdateDone(result) {
   if ($modalSpinner) $modalSpinner.classList.remove("spinning");
   if ($btnCloseModal) $btnCloseModal.disabled = false;
-  if (success) {
+  if (result === true) {
     if ($modalStatus) $modalStatus.textContent = "✓ Update complete";
     if ($btnReboot) $btnReboot.style.display = "inline-flex";
+  } else if (result === "reboot_required") {
+    if ($modalStatus) $modalStatus.textContent = "✓ Update complete — reboot required";
+    if ($btnReboot) $btnReboot.style.display = "inline-flex";
   } else {
     if ($modalStatus) $modalStatus.textContent = "✗ Update failed";
     if ($btnSave) $btnSave.style.display = "inline-flex";
diff --git a/modules/core/sovran-hub.nix b/modules/core/sovran-hub.nix
index e8400b4..ccf3929 100644
--- a/modules/core/sovran-hub.nix
+++ b/modules/core/sovran-hub.nix
@@ -143,8 +143,21 @@ let
     echo ""
 
     if [ "$RC" -eq 0 ]; then
-      echo "── Step 2/3: nixos-rebuild switch ──────────────────"
-      if ! nixos-rebuild switch --flake /etc/nixos --print-build-logs 2>&1; then
+      echo "── Step 2/3: nixos-rebuild ──────────────────────────"
+      if nixos-rebuild switch --flake /etc/nixos --print-build-logs 2>&1; then
+        echo "[OK] switch succeeded"
+      elif grep -q "switchInhibitors\|Pre-switch checks failed" "$LOG" 2>/dev/null; then
+        echo ""
+        echo "  ✓ Build succeeded — a reboot is required to apply this update"
+        echo "  (Critical system components changed; running nixos-rebuild boot instead)"
+        if nixos-rebuild boot --flake /etc/nixos --print-build-logs 2>&1; then
+          echo "REBOOT_REQUIRED" > "$STATUS"
+          exit 0
+        else
+          echo "[ERROR] nixos-rebuild boot also failed"
+          RC=1
+        fi
+      else
         echo "[ERROR] nixos-rebuild switch failed"
         RC=1
       fi
@@ -197,6 +210,17 @@ let
       echo "  ✓ Rebuild completed successfully"
       echo "══════════════════════════════════════════════════"
       echo "SUCCESS" > "$STATUS"
+    elif grep -q "switchInhibitors\|Pre-switch checks failed" "$LOG" 2>/dev/null; then
+      echo ""
+      echo "  ✓ Build succeeded — a reboot is required to apply this rebuild"
+      echo "  (Critical system components changed; running nixos-rebuild boot instead)"
+      if nixos-rebuild boot --flake /etc/nixos --print-build-logs 2>&1; then
+        echo "REBOOT_REQUIRED" > "$STATUS"
+      else
+        echo "[ERROR] nixos-rebuild boot also failed"
+        echo "FAILED" > "$STATUS"
+        exit 1
+      fi
     else
       echo ""
       echo "══════════════════════════════════════════════════"