diff --git a/.claude/launch.json b/.claude/launch.json
index 8a2ca19..04ee57b 100644
--- a/.claude/launch.json
+++ b/.claude/launch.json
@@ -3,17 +3,15 @@
   "configurations": [
     {
       "name": "backend",
-      "runtimeExecutable": "npx",
-      "runtimeArgs": ["tsx", "src/index.ts"],
-      "port": 3001,
-      "cwd": "server"
+      "runtimeExecutable": "npm",
+      "runtimeArgs": ["run", "--workspace=server", "dev"],
+      "port": 3002
     },
     {
       "name": "frontend",
-      "runtimeExecutable": "npx",
-      "runtimeArgs": ["vite", "--port", "5173"],
-      "port": 5173,
-      "cwd": "client"
+      "runtimeExecutable": "npm",
+      "runtimeArgs": ["run", "--workspace=client", "dev"],
+      "port": 5173
     }
   ]
 }
diff --git a/client/src/App.tsx b/client/src/App.tsx
index 3ee718e..53afc34 100644
--- a/client/src/App.tsx
+++ b/client/src/App.tsx
@@ -14,7 +14,6 @@ import { ContainersPage } from "@/components/pages/ContainersPage"
 import { MemoryPage } from "@/components/pages/MemoryPage"
 import { StoragePage } from "@/components/pages/StoragePage"
 import { NetworkPage } from "@/components/pages/NetworkPage"
-import { SettingsPage } from "@/components/pages/SettingsPage"
 import { NotificationsPage } from "@/components/pages/NotificationsPage"
 import { LoginPage } from "@/components/ui/animated-characters-login-page"
 import { useServerHealth } from "@/hooks/useServerHealth"
@@ -45,12 +44,11 @@ const queryClient = new QueryClient({
 })
 
 const PAGE_TITLES: Record<string, string> = {
-  dashboard: "Dashboard",
-  containers: "Containers",
-  memory: "Memory",
-  storage: "Storage",
-  network: "Network",
-  settings: "Settings",
+  dashboard:     "Dashboard",
+  containers:    "Containers",
+  memory:        "Memory",
+  storage:       "Storage",
+  network:       "Network",
   notifications: "Notifications",
 }
 
@@ -136,7 +134,7 @@ function DashboardContent({ activePage, onLogout }: { activePage: string; onLogo
   const system = data.system
   const memory = data.memory
   const disk = data.disk
-  const containers = data.docker ?? []
+  const containers = Array.isArray(data.docker) ? data.docker : []
   const nginx = data.nginx
 
   const renderPage = () => {
@@ -149,8 +147,6 @@ function DashboardContent({ activePage, onLogout }: { activePage: string; onLogo
         return <StoragePage disk={disk} />
       case "network":
         return <NetworkPage containers={containers} nginx={nginx} />
-      case "settings":
-        return <SettingsPage />
       case "notifications":
         return <NotificationsPage />
       default:
diff --git a/client/src/components/layout/Header.tsx b/client/src/components/layout/Header.tsx
index f54facc..588ec3f 100644
--- a/client/src/components/layout/Header.tsx
+++ b/client/src/components/layout/Header.tsx
@@ -1,4 +1,4 @@
-import { RefreshCw, Bell } from "lucide-react"
+import { RefreshCw } from "lucide-react"
 import { cn } from "@/lib/utils"
 import {
   Select,
@@ -70,13 +70,6 @@ export function Header({
           <RefreshCw className="size-4 text-muted-foreground" />
         </button>
 
-        <button
-          className="flex size-9 items-center justify-center rounded-lg border transition-colors hover:bg-muted"
-          aria-label="Notifications"
-        >
-          <Bell className="size-4 text-muted-foreground" />
-        </button>
-
         <div className="flex size-9 items-center justify-center rounded-full bg-primary text-xs font-semibold text-primary-foreground">
           BS
         </div>
diff --git a/client/src/components/layout/Sidebar.tsx b/client/src/components/layout/Sidebar.tsx
index 463c532..a77b65f 100644
--- a/client/src/components/layout/Sidebar.tsx
+++ b/client/src/components/layout/Sidebar.tsx
@@ -4,14 +4,15 @@ import {
   MemoryStick,
   HardDrive,
   Wifi,
-  Bell,
   Settings,
   HelpCircle,
   Server,
   LogOut,
+  Bell,
 } from "lucide-react"
 import { cn } from "@/lib/utils"
 import { Separator } from "@/components/ui/separator"
+import { useNotificationSummary } from "@/hooks/useNotifications"
 
 interface NavItem {
   id: string
@@ -20,17 +21,17 @@ interface NavItem {
 }
 
 const mainNav: NavItem[] = [
-  { id: "dashboard", label: "Dashboard", icon: LayoutDashboard },
-  { id: "containers", label: "Containers", icon: Container },
-  { id: "memory", label: "Memory", icon: MemoryStick },
-  { id: "storage", label: "Storage", icon: HardDrive },
-  { id: "network", label: "Network", icon: Wifi },
-  { id: "notifications", label: "Notifications", icon: Bell },
+  { id: "dashboard",     label: "Dashboard",     icon: LayoutDashboard },
+  { id: "containers",    label: "Containers",     icon: Container },
+  { id: "memory",        label: "Memory",         icon: MemoryStick },
+  { id: "storage",       label: "Storage",        icon: HardDrive },
+  { id: "network",       label: "Network",        icon: Wifi },
+  { id: "notifications", label: "Notifications",  icon: Bell },
 ]
 
 const bottomNav: NavItem[] = [
-  { id: "settings", label: "Settings", icon: Settings },
-  { id: "help", label: "Help & Support", icon: HelpCircle },
+  { id: "settings", label: "Settings",      icon: Settings },
+  { id: "help",     label: "Help & Support", icon: HelpCircle },
 ]
 
 interface SidebarProps {
@@ -43,10 +44,12 @@ function NavButton({
   item,
   active,
   onClick,
+  badge,
 }: {
   item: NavItem
   active: boolean
   onClick: () => void
+  badge?: number
 }) {
   const Icon = item.icon
   return (
@@ -60,11 +63,25 @@ function NavButton({
       )}
     >
       <Icon className="size-5 shrink-0" />
-      <span>{item.label}</span>
+      <span className="flex-1 text-left">{item.label}</span>
+      {badge !== undefined && badge > 0 && (
+        <span className={cn(
+          "inline-flex size-5 items-center justify-center rounded-full text-xs font-bold",
+          active ? "bg-primary-foreground text-primary" : "bg-red-500 text-white"
+        )}>
+          {badge > 99 ? "99+" : badge}
+        </span>
+      )}
     </button>
   )
 }
 
+function NotificationBadge({ active, onClick, item }: { active: boolean; onClick: () => void; item: NavItem }) {
+  const { data } = useNotificationSummary()
+  const count = data ? data.activeCriticals + data.activeWarnings : 0
+  return <NavButton item={item} active={active} onClick={onClick} badge={count} />
+}
+
 export function Sidebar({ activePage, onNavigate, onLogout }: SidebarProps) {
   return (
     <aside className="flex h-screen w-60 shrink-0 flex-col border-r bg-sidebar-background">
@@ -80,14 +97,23 @@ export function Sidebar({ activePage, onNavigate, onLogout }: SidebarProps) {
 
       {/* Main nav */}
       <nav className="flex flex-1 flex-col gap-1 px-3">
-        {mainNav.map((item) => (
-          <NavButton
-            key={item.id}
-            item={item}
-            active={activePage === item.id}
-            onClick={() => onNavigate(item.id)}
-          />
-        ))}
+        {mainNav.map((item) =>
+          item.id === "notifications" ? (
+            <NotificationBadge
+              key={item.id}
+              item={item}
+              active={activePage === item.id}
+              onClick={() => onNavigate(item.id)}
+            />
+          ) : (
+            <NavButton
+              key={item.id}
+              item={item}
+              active={activePage === item.id}
+              onClick={() => onNavigate(item.id)}
+            />
+          )
+        )}
 
         <Separator className="my-4" />
 
diff --git a/client/src/components/pages/NotificationsPage.tsx b/client/src/components/pages/NotificationsPage.tsx
index 49ee566..2de159e 100644
--- a/client/src/components/pages/NotificationsPage.tsx
+++ b/client/src/components/pages/NotificationsPage.tsx
@@ -1,169 +1,551 @@
-import { useEffect, useState, useCallback } from "react"
-import { AlertTriangle, AlertCircle, Info, CheckCircle2, Mail, MailX, CheckCheck } from "lucide-react"
+import { useState } from "react"
+import { Bell, CheckCheck, Trash2, Mail, Save, Plus, X, AlertTriangle, AlertCircle, Info, Send } from "lucide-react"
+import { Card, CardContent, CardHeader, CardTitle } from "@/components/ui/card"
+import { Button } from "@/components/ui/button"
+import { Badge } from "@/components/ui/badge"
+import { Input } from "@/components/ui/input"
+import { Label } from "@/components/ui/label"
+import { Checkbox } from "@/components/ui/checkbox"
+import { Select, SelectContent, SelectItem, SelectTrigger, SelectValue } from "@/components/ui/select"
+import { Table, TableBody, TableCell, TableHead, TableHeader, TableRow } from "@/components/ui/table"
+import { Separator } from "@/components/ui/separator"
+import {
+  useNotifications,
+  useAcknowledgeAlert,
+  useDeleteAlert,
+  useClearResolved,
+  useThresholds,
+  useUpdateThresholds,
+  usePreferences,
+  useUpdatePreferences,
+  useSendTestEmail,
+  useSendSampleAlerts,
+} from "@/hooks/useNotifications"
+import type { AlertRecord, AlertSeverity, MetricKey, ThresholdConfig, EmailRecipient } from "@/types/notifications"
+import { METRIC_LABELS } from "@/types/notifications"
+import { cn } from "@/lib/utils"
 
-interface Notification {
-  id: string
-  type: "error" | "warning" | "info" | "recovery"
-  title: string
-  message: string
-  source: string
-  timestamp: string
-  read: boolean
-  emailSent: boolean
+type Tab = "history" | "thresholds" | "email"
+
+// ── Severity badge ──
+function SeverityBadge({ severity }: { severity: AlertSeverity }) {
+  if (severity === "critical") return (
+    <Badge className="bg-red-100 text-red-700 border-red-200 gap-1">
+      <AlertCircle className="size-3" />critical
+    </Badge>
+  )
+  if (severity === "warning") return (
+    <Badge className="bg-amber-100 text-amber-700 border-amber-200 gap-1">
+      <AlertTriangle className="size-3" />warning
+    </Badge>
+  )
+  return (
+    <Badge className="bg-blue-100 text-blue-700 border-blue-200 gap-1">
+      <Info className="size-3" />info
+    </Badge>
+  )
 }
 
-const TOKEN_KEY = "eventify-auth-token"
-
-function getToken() {
-  return localStorage.getItem(TOKEN_KEY) ?? ""
-}
-
-async function apiFetch(path: string, opts: RequestInit = {}) {
-  const res = await fetch(path, {
-    ...opts,
-    headers: {
-      "Content-Type": "application/json",
-      Authorization: `Bearer ${getToken()}`,
-      ...opts.headers,
-    },
-  })
-  if (!res.ok) throw new Error("Request failed")
-  return res.json()
-}
-
-function timeAgo(ts: string): string {
-  const diff = Date.now() - new Date(ts).getTime()
-  const mins = Math.floor(diff / 60000)
-  if (mins < 1) return "Just now"
+function timeAgo(iso: string) {
+  const diff = Date.now() - new Date(iso).getTime()
+  const mins = Math.floor(diff / 60_000)
+  if (mins < 1) return "just now"
   if (mins < 60) return `${mins}m ago`
   const hrs = Math.floor(mins / 60)
   if (hrs < 24) return `${hrs}h ago`
-  const days = Math.floor(hrs / 24)
-  return `${days}d ago`
+  return `${Math.floor(hrs / 24)}d ago`
 }
 
-const typeConfig = {
-  error: { icon: AlertCircle, color: "text-red-500", bg: "bg-red-50 border-red-200", badge: "bg-red-100 text-red-700" },
-  warning: { icon: AlertTriangle, color: "text-amber-500", bg: "bg-amber-50 border-amber-200", badge: "bg-amber-100 text-amber-700" },
-  info: { icon: Info, color: "text-blue-500", bg: "bg-blue-50 border-blue-200", badge: "bg-blue-100 text-blue-700" },
-  recovery: { icon: CheckCircle2, color: "text-green-500", bg: "bg-green-50 border-green-200", badge: "bg-green-100 text-green-700" },
-}
+// ── Tab 1: Alert History ──
+function AlertHistoryTab() {
+  const [page, setPage] = useState(1)
+  const [statusFilter, setStatusFilter] = useState("all")
+  const limit = 20
 
-export function NotificationsPage() {
-  const [notifications, setNotifications] = useState<Notification[]>([])
-  const [loading, setLoading] = useState(true)
+  const { data, isLoading } = useNotifications(page, limit, statusFilter)
+  const acknowledge = useAcknowledgeAlert()
+  const deleteAlert = useDeleteAlert()
+  const clearResolved = useClearResolved()
 
-  const load = useCallback(async () => {
-    try {
-      setLoading(true)
-      const data = await apiFetch("/api/notifications?limit=100")
-      setNotifications(data)
-    } catch {
-    } finally {
-      setLoading(false)
-    }
-  }, [])
-
-  useEffect(() => { load() }, [load])
-
-  const markRead = async (id: string) => {
-    setNotifications(prev => prev.map(n => n.id === id ? { ...n, read: true } : n))
-    try { await apiFetch(`/api/notifications/${id}/read`, { method: "POST" }) } catch {}
-  }
-
-  const markAllRead = async () => {
-    setNotifications(prev => prev.map(n => ({ ...n, read: true })))
-    try { await apiFetch("/api/notifications/read-all", { method: "POST" }) } catch {}
-  }
-
-  const unreadCount = notifications.filter(n => !n.read).length
-
-  if (loading) {
-    return (
-      <div className="flex justify-center py-12">
-        <div className="h-8 w-8 animate-spin rounded-full border-4 border-primary border-t-transparent" />
-      </div>
-    )
-  }
+  const alerts: AlertRecord[] = data?.alerts ?? []
+  const total = data?.total ?? 0
+  const totalPages = Math.max(1, Math.ceil(total / limit))
 
   return (
-    <div className="mx-auto max-w-3xl space-y-6">
-      {/* Header */}
-      <div className="flex items-center justify-between">
-        <div>
-          <h2 className="text-lg font-semibold text-foreground">
-            Notifications
-            {unreadCount > 0 && (
-              <span className="ml-2 inline-flex items-center rounded-full bg-red-100 px-2 py-0.5 text-xs font-medium text-red-700">
-                {unreadCount} unread
-              </span>
-            )}
-          </h2>
-          <p className="text-sm text-muted-foreground">Server alerts and error notifications</p>
+    <div className="space-y-4">
+      <div className="flex items-center justify-between gap-3 flex-wrap">
+        <div className="flex gap-2">
+          {(["all", "active", "resolved"] as const).map(s => (
+            <button
+              key={s}
+              onClick={() => { setStatusFilter(s); setPage(1) }}
+              className={cn(
+                "px-3 py-1.5 rounded-md text-sm font-medium transition-colors capitalize",
+                statusFilter === s
+                  ? "bg-primary text-primary-foreground"
+                  : "bg-muted text-muted-foreground hover:bg-muted/80"
+              )}
+            >
+              {s}
+            </button>
+          ))}
         </div>
-        {unreadCount > 0 && (
-          <button
-            onClick={markAllRead}
-            className="inline-flex items-center gap-2 rounded-lg border px-3 py-2 text-sm font-medium text-muted-foreground hover:bg-muted"
-          >
-            <CheckCheck className="size-4" />
-            Mark all read
-          </button>
-        )}
+        <Button
+          variant="outline"
+          size="sm"
+          onClick={() => clearResolved.mutate()}
+          disabled={clearResolved.isPending}
+          className="text-red-600 border-red-200 hover:bg-red-50"
+        >
+          <Trash2 className="size-4 mr-1.5" />
+          Clear Resolved
+        </Button>
       </div>
 
-      {/* Notification List */}
-      {notifications.length === 0 ? (
-        <div className="rounded-xl border bg-card px-5 py-16 text-center">
-          <CheckCircle2 className="mx-auto size-12 text-green-400" />
-          <h3 className="mt-4 font-medium text-foreground">All clear</h3>
-          <p className="mt-1 text-sm text-muted-foreground">No notifications yet. You'll see alerts here when issues are detected.</p>
-        </div>
-      ) : (
-        <div className="space-y-3">
-          {notifications.map(n => {
-            const cfg = typeConfig[n.type]
-            const Icon = cfg.icon
-            return (
-              <div
-                key={n.id}
-                onClick={() => !n.read && markRead(n.id)}
-                className={`cursor-pointer rounded-xl border p-4 transition-colors ${
-                  n.read ? "bg-card border-border" : `${cfg.bg}`
-                }`}
-              >
-                <div className="flex items-start gap-3">
-                  <div className={`mt-0.5 ${cfg.color}`}>
-                    <Icon className="size-5" />
-                  </div>
-                  <div className="flex-1 min-w-0">
-                    <div className="flex items-center gap-2">
-                      <span className="font-medium text-foreground">{n.title}</span>
-                      <span className={`rounded-full px-2 py-0.5 text-[10px] font-semibold uppercase ${cfg.badge}`}>
-                        {n.type}
-                      </span>
-                      {n.emailSent ? (
-                        <span title="Email sent"><Mail className="size-3.5 text-green-500" /></span>
+      <Card>
+        <CardContent className="p-0">
+          {isLoading ? (
+            <div className="p-8 text-center text-muted-foreground text-sm">Loading…</div>
+          ) : alerts.length === 0 ? (
+            <div className="p-12 text-center">
+              <Bell className="size-10 mx-auto text-muted-foreground/40 mb-3" />
+              <p className="text-sm text-muted-foreground">No alerts found</p>
+            </div>
+          ) : (
+            <Table>
+              <TableHeader>
+                <TableRow>
+                  <TableHead>Severity</TableHead>
+                  <TableHead>Metric</TableHead>
+                  <TableHead>Message</TableHead>
+                  <TableHead>Value</TableHead>
+                  <TableHead>Time</TableHead>
+                  <TableHead>Status</TableHead>
+                  <TableHead className="text-right">Actions</TableHead>
+                </TableRow>
+              </TableHeader>
+              <TableBody>
+                {alerts.map(alert => (
+                  <TableRow key={alert.id} className={alert.acknowledged ? "opacity-60" : ""}>
+                    <TableCell><SeverityBadge severity={alert.severity} /></TableCell>
+                    <TableCell className="font-medium text-sm">{METRIC_LABELS[alert.metric]}</TableCell>
+                    <TableCell className="text-sm text-muted-foreground max-w-xs truncate">{alert.message}</TableCell>
+                    <TableCell className="text-sm font-mono">{String(alert.value)}</TableCell>
+                    <TableCell className="text-sm text-muted-foreground whitespace-nowrap">{timeAgo(alert.firedAt)}</TableCell>
+                    <TableCell>
+                      {alert.resolvedAt ? (
+                        <Badge variant="outline" className="text-green-600 border-green-200">resolved</Badge>
                       ) : (
-                        <span title="Email not sent"><MailX className="size-3.5 text-muted-foreground" /></span>
+                        <Badge variant="outline" className="text-orange-600 border-orange-200">active</Badge>
                       )}
-                      {!n.read && (
-                        <span className="size-2 rounded-full bg-blue-500" />
-                      )}
-                    </div>
-                    <p className="mt-1 text-sm text-muted-foreground">{n.message}</p>
-                    <div className="mt-2 flex items-center gap-3 text-xs text-muted-foreground">
-                      <span>{n.source}</span>
-                      <span>&middot;</span>
-                      <span>{timeAgo(n.timestamp)}</span>
-                    </div>
-                  </div>
-                </div>
-              </div>
-            )
-          })}
+                    </TableCell>
+                    <TableCell className="text-right">
+                      <div className="flex justify-end gap-1">
+                        {!alert.acknowledged && (
+                          <button
+                            onClick={() => acknowledge.mutate(alert.id)}
+                            className="p-1.5 rounded hover:bg-muted transition-colors"
+                            title="Acknowledge"
+                          >
+                            <CheckCheck className="size-4 text-muted-foreground" />
+                          </button>
+                        )}
+                        <button
+                          onClick={() => deleteAlert.mutate(alert.id)}
+                          className="p-1.5 rounded hover:bg-red-50 transition-colors"
+                          title="Delete"
+                        >
+                          <Trash2 className="size-4 text-red-400" />
+                        </button>
+                      </div>
+                    </TableCell>
+                  </TableRow>
+                ))}
+              </TableBody>
+            </Table>
+          )}
+        </CardContent>
+      </Card>
+
+      {totalPages > 1 && (
+        <div className="flex items-center justify-between text-sm text-muted-foreground">
+          <span>Showing {((page - 1) * limit) + 1}–{Math.min(page * limit, total)} of {total}</span>
+          <div className="flex gap-1">
+            <Button variant="outline" size="sm" disabled={page === 1} onClick={() => setPage(p => p - 1)}>Prev</Button>
+            <Button variant="outline" size="sm" disabled={page === totalPages} onClick={() => setPage(p => p + 1)}>Next</Button>
+          </div>
         </div>
       )}
     </div>
   )
 }
+
+// ── Tab 2: Thresholds ──
+const THRESHOLD_DESCRIPTIONS: Record<MetricKey, string> = {
+  cpu_percent:        "CPU utilization percentage",
+  load_avg_1m:        "1-minute load average",
+  memory_percent:     "RAM usage percentage",
+  disk_percent:       "Disk usage percentage",
+  nginx_status:       "Fires if Nginx is not active (boolean)",
+  container_stopped:  "Fires if any Docker container is not running",
+  connections_total:  "Total active TCP connections (DDoS indicator)",
+  connections_per_ip: "Max connections from a single IP (DDoS indicator)",
+  request_rate:       "HTTP requests per minute (API abuse detection)",
+  error_rate_5xx:     "Server errors (5xx) per minute",
+}
+
+function ThresholdsTab() {
+  const { data, isLoading } = useThresholds()
+  const update = useUpdateThresholds()
+  const [local, setLocal] = useState<ThresholdConfig[] | null>(null)
+  const [saved, setSaved] = useState(false)
+
+  const thresholds: ThresholdConfig[] = local ?? data?.thresholds ?? []
+  const isBooleanMetric = (m: MetricKey) => m === "nginx_status" || m === "container_stopped"
+
+  function handleChange(metric: MetricKey, field: keyof ThresholdConfig, value: unknown) {
+    const base = local ?? data?.thresholds ?? []
+    setLocal(base.map(t => t.metric === metric ? { ...t, [field]: value } : t))
+    setSaved(false)
+  }
+
+  function handleSave() {
+    if (!data) return
+    update.mutate(
+      { thresholds, updatedAt: new Date().toISOString() },
+      {
+        onSuccess: () => { setLocal(null); setSaved(true); setTimeout(() => setSaved(false), 3000) },
+      }
+    )
+  }
+
+  if (isLoading) return <div className="p-8 text-center text-muted-foreground text-sm">Loading…</div>
+
+  return (
+    <div className="space-y-4">
+      <div className="grid gap-4 sm:grid-cols-2">
+        {thresholds.map(t => (
+          <Card key={t.metric}>
+            <CardHeader className="pb-3">
+              <div className="flex items-center justify-between">
+                <CardTitle className="text-sm font-semibold">{METRIC_LABELS[t.metric]}</CardTitle>
+                <div className="flex items-center gap-2">
+                  <Label htmlFor={`en-${t.metric}`} className="text-xs text-muted-foreground cursor-pointer">Enabled</Label>
+                  <Checkbox
+                    id={`en-${t.metric}`}
+                    checked={t.enabled}
+                    onCheckedChange={v => handleChange(t.metric, "enabled", !!v)}
+                  />
+                </div>
+              </div>
+              <p className="text-xs text-muted-foreground">{THRESHOLD_DESCRIPTIONS[t.metric]}</p>
+            </CardHeader>
+            {!isBooleanMetric(t.metric) && (
+              <CardContent className="pt-0 grid grid-cols-2 gap-3">
+                <div className="space-y-1">
+                  <Label className="text-xs text-amber-600">Warning (%)</Label>
+                  <Input
+                    type="number"
+                    min={0} max={100} step={1}
+                    value={t.warning}
+                    onChange={e => handleChange(t.metric, "warning", parseFloat(e.target.value))}
+                    className="h-8 text-sm"
+                    disabled={!t.enabled}
+                  />
+                </div>
+                <div className="space-y-1">
+                  <Label className="text-xs text-red-600">Critical (%)</Label>
+                  <Input
+                    type="number"
+                    min={0} max={100} step={1}
+                    value={t.critical}
+                    onChange={e => handleChange(t.metric, "critical", parseFloat(e.target.value))}
+                    className="h-8 text-sm"
+                    disabled={!t.enabled}
+                  />
+                </div>
+              </CardContent>
+            )}
+          </Card>
+        ))}
+      </div>
+
+      <div className="flex items-center gap-3">
+        <Button onClick={handleSave} disabled={update.isPending} className="gap-2">
+          <Save className="size-4" />
+          {update.isPending ? "Saving…" : "Save Thresholds"}
+        </Button>
+        {saved && <span className="text-sm text-green-600 font-medium">Saved!</span>}
+      </div>
+    </div>
+  )
+}
+
+// ── Tab 3: Email Settings ──
+function EmailSettingsTab() {
+  const { data, isLoading } = usePreferences()
+  const update = useUpdatePreferences()
+  const testEmail = useSendTestEmail()
+  const sampleAlerts = useSendSampleAlerts()
+
+  const [local, setLocal] = useState<{ recipients: EmailRecipient[]; cooldownMinutes: number; enabledSeverities: AlertSeverity[] } | null>(null)
+  const [newEmail, setNewEmail] = useState("")
+  const [newName, setNewName] = useState("")
+  const [testTo, setTestTo] = useState("")
+  const [testMsg, setTestMsg] = useState("")
+  const [sampleMsg, setSampleMsg] = useState("")
+  const [saved, setSaved] = useState(false)
+
+  const prefs = local ?? (data ? { recipients: data.recipients, cooldownMinutes: data.cooldownMinutes, enabledSeverities: data.enabledSeverities } : null)
+
+  function setPrefs(patch: Partial<typeof prefs>) {
+    const base = prefs ?? { recipients: [], cooldownMinutes: 15, enabledSeverities: ["critical", "warning", "info"] as AlertSeverity[] }
+    setLocal({ ...base, ...patch })
+    setSaved(false)
+  }
+
+  function addRecipient() {
+    if (!newEmail.trim() || !newName.trim()) return
+    setPrefs({ recipients: [...(prefs?.recipients ?? []), { email: newEmail.trim(), name: newName.trim(), enabled: true }] })
+    setNewEmail(""); setNewName("")
+  }
+
+  function removeRecipient(email: string) {
+    setPrefs({ recipients: (prefs?.recipients ?? []).filter(r => r.email !== email) })
+  }
+
+  function toggleRecipient(email: string) {
+    setPrefs({ recipients: (prefs?.recipients ?? []).map(r => r.email === email ? { ...r, enabled: !r.enabled } : r) })
+  }
+
+  function toggleSeverity(sev: AlertSeverity) {
+    const current = prefs?.enabledSeverities ?? []
+    const next = current.includes(sev) ? current.filter(s => s !== sev) : [...current, sev]
+    setPrefs({ enabledSeverities: next })
+  }
+
+  function handleSave() {
+    if (!data || !prefs) return
+    update.mutate(
+      { ...data, ...prefs, updatedAt: new Date().toISOString() },
+      { onSuccess: () => { setLocal(null); setSaved(true); setTimeout(() => setSaved(false), 3000) } }
+    )
+  }
+
+  function handleTestEmail() {
+    if (!testTo.trim()) return
+    testEmail.mutate(testTo.trim(), {
+      onSuccess: (r) => setTestMsg(r.message),
+      onError: (e) => setTestMsg(`Error: ${e.message}`),
+    })
+  }
+
+  if (isLoading || !prefs) return <div className="p-8 text-center text-muted-foreground text-sm">Loading…</div>
+
+  return (
+    <div className="space-y-6 max-w-2xl">
+      {/* Recipients */}
+      <Card>
+        <CardHeader>
+          <CardTitle className="text-sm font-semibold">Email Recipients</CardTitle>
+        </CardHeader>
+        <CardContent className="space-y-3">
+          {prefs.recipients.map(r => (
+            <div key={r.email} className="flex items-center gap-3">
+              <Checkbox checked={r.enabled} onCheckedChange={() => toggleRecipient(r.email)} />
+              <div className="flex-1 min-w-0">
+                <p className="text-sm font-medium">{r.name}</p>
+                <p className="text-xs text-muted-foreground">{r.email}</p>
+              </div>
+              <button onClick={() => removeRecipient(r.email)} className="p-1 rounded hover:bg-red-50 transition-colors">
+                <X className="size-4 text-red-400" />
+              </button>
+            </div>
+          ))}
+
+          <Separator />
+
+          <div className="flex gap-2 flex-wrap">
+            <Input
+              placeholder="Name"
+              value={newName}
+              onChange={e => setNewName(e.target.value)}
+              className="h-8 text-sm w-32"
+            />
+            <Input
+              placeholder="email@example.com"
+              value={newEmail}
+              onChange={e => setNewEmail(e.target.value)}
+              className="h-8 text-sm flex-1 min-w-40"
+            />
+            <Button size="sm" variant="outline" onClick={addRecipient} className="h-8 gap-1">
+              <Plus className="size-3.5" />Add
+            </Button>
+          </div>
+        </CardContent>
+      </Card>
+
+      {/* Alert Severity Filter */}
+      <Card>
+        <CardHeader>
+          <CardTitle className="text-sm font-semibold">Email for Severities</CardTitle>
+        </CardHeader>
+        <CardContent className="flex gap-4">
+          {(["critical", "warning", "info"] as AlertSeverity[]).map(sev => (
+            <div key={sev} className="flex items-center gap-2">
+              <Checkbox
+                id={`sev-${sev}`}
+                checked={prefs.enabledSeverities.includes(sev)}
+                onCheckedChange={() => toggleSeverity(sev)}
+              />
+              <Label htmlFor={`sev-${sev}`} className="capitalize cursor-pointer text-sm">{sev}</Label>
+            </div>
+          ))}
+        </CardContent>
+      </Card>
+
+      {/* Cooldown */}
+      <Card>
+        <CardHeader>
+          <CardTitle className="text-sm font-semibold">Alert Cooldown</CardTitle>
+          <p className="text-xs text-muted-foreground">Minimum time between repeated emails for the same metric</p>
+        </CardHeader>
+        <CardContent>
+          <Select
+            value={String(prefs.cooldownMinutes)}
+            onValueChange={v => setPrefs({ cooldownMinutes: parseInt(v) })}
+          >
+            <SelectTrigger className="w-40">
+              <SelectValue />
+            </SelectTrigger>
+            <SelectContent>
+              <SelectItem value="5">5 minutes</SelectItem>
+              <SelectItem value="10">10 minutes</SelectItem>
+              <SelectItem value="15">15 minutes</SelectItem>
+              <SelectItem value="30">30 minutes</SelectItem>
+              <SelectItem value="60">60 minutes</SelectItem>
+            </SelectContent>
+          </Select>
+        </CardContent>
+      </Card>
+
+      {/* Test Email */}
+      <Card>
+        <CardHeader>
+          <CardTitle className="text-sm font-semibold">Test SMTP Connection</CardTitle>
+        </CardHeader>
+        <CardContent className="space-y-3">
+          <div className="flex gap-2">
+            <Input
+              placeholder="Send test to email@example.com"
+              value={testTo}
+              onChange={e => setTestTo(e.target.value)}
+              className="h-8 text-sm flex-1"
+            />
+            <Button size="sm" variant="outline" onClick={handleTestEmail} disabled={testEmail.isPending} className="h-8 gap-1.5">
+              <Mail className="size-3.5" />
+              {testEmail.isPending ? "Sending…" : "Send Test"}
+            </Button>
+          </div>
+          {testMsg && (
+            <p className={cn("text-sm", testMsg.startsWith("Error") ? "text-red-600" : "text-green-600")}>
+              {testMsg}
+            </p>
+          )}
+        </CardContent>
+      </Card>
+
+      {/* Send All Sample Alerts */}
+      <Card>
+        <CardHeader>
+          <CardTitle className="text-sm font-semibold">Preview All Alert Emails</CardTitle>
+          <p className="text-xs text-muted-foreground">Send sample emails for every alert type — Critical, Warning, Info, and Recovery</p>
+        </CardHeader>
+        <CardContent className="space-y-3">
+          <div className="flex gap-2">
+            <Input
+              placeholder="Send samples to email@example.com"
+              value={testTo}
+              onChange={e => setTestTo(e.target.value)}
+              className="h-8 text-sm flex-1"
+            />
+            <Button
+              size="sm"
+              onClick={() => {
+                if (!testTo.trim()) return
+                sampleAlerts.mutate(testTo.trim(), {
+                  onSuccess: (r) => setSampleMsg(r.message),
+                  onError: (e) => setSampleMsg(`Error: ${e.message}`),
+                })
+              }}
+              disabled={sampleAlerts.isPending}
+              className="h-8 gap-1.5"
+            >
+              <Send className="size-3.5" />
+              {sampleAlerts.isPending ? "Sending 7 emails…" : "Send All Samples"}
+            </Button>
+          </div>
+          <div className="flex flex-wrap gap-1.5">
+            <span className="text-xs bg-red-100 text-red-700 px-2 py-0.5 rounded-full font-medium">Critical</span>
+            <span className="text-xs bg-amber-100 text-amber-700 px-2 py-0.5 rounded-full font-medium">Warning</span>
+            <span className="text-xs bg-blue-100 text-blue-700 px-2 py-0.5 rounded-full font-medium">Info</span>
+            <span className="text-xs bg-red-100 text-red-700 px-2 py-0.5 rounded-full font-medium">DDoS</span>
+            <span className="text-xs bg-amber-100 text-amber-700 px-2 py-0.5 rounded-full font-medium">API Rate</span>
+            <span className="text-xs bg-red-100 text-red-700 px-2 py-0.5 rounded-full font-medium">5xx Errors</span>
+            <span className="text-xs bg-green-100 text-green-700 px-2 py-0.5 rounded-full font-medium">Recovery</span>
+          </div>
+          {sampleMsg && (
+            <p className={cn("text-sm", sampleMsg.startsWith("Error") ? "text-red-600" : "text-green-600")}>
+              {sampleMsg}
+            </p>
+          )}
+        </CardContent>
+      </Card>
+
+      <div className="flex items-center gap-3">
+        <Button onClick={handleSave} disabled={update.isPending} className="gap-2">
+          <Save className="size-4" />
+          {update.isPending ? "Saving…" : "Save Settings"}
+        </Button>
+        {saved && <span className="text-sm text-green-600 font-medium">Saved!</span>}
+      </div>
+    </div>
+  )
+}
+
+// ── Main Page ──
+export function NotificationsPage() {
+  const [tab, setTab] = useState<Tab>("history")
+
+  const tabs: { id: Tab; label: string }[] = [
+    { id: "history",    label: "Alert History" },
+    { id: "thresholds", label: "Thresholds" },
+    { id: "email",      label: "Email Settings" },
+  ]
+
+  return (
+    <div className="space-y-6">
+      {/* Tab bar */}
+      <div className="flex gap-1 border-b">
+        {tabs.map(t => (
+          <button
+            key={t.id}
+            onClick={() => setTab(t.id)}
+            className={cn(
+              "px-4 py-2.5 text-sm font-medium border-b-2 -mb-px transition-colors",
+              tab === t.id
+                ? "border-primary text-foreground"
+                : "border-transparent text-muted-foreground hover:text-foreground"
+            )}
+          >
+            {t.label}
+          </button>
+        ))}
+      </div>
+
+      {tab === "history"    && <AlertHistoryTab />}
+      {tab === "thresholds" && <ThresholdsTab />}
+      {tab === "email"      && <EmailSettingsTab />}
+    </div>
+  )
+}
diff --git a/client/src/components/pages/SettingsPage.tsx b/client/src/components/pages/SettingsPage.tsx
deleted file mode 100644
index 46908b6..0000000
--- a/client/src/components/pages/SettingsPage.tsx
+++ /dev/null
@@ -1,233 +0,0 @@
-import { useEffect, useState, useCallback } from "react"
-import { UserPlus, Trash2, Shield, Code, Bell, BellOff, Check, X } from "lucide-react"
-
-interface MonitorUser {
-  id: string
-  email: string
-  name: string
-  role: "developer" | "server-admin"
-  notifyOnError: boolean
-  createdAt: string
-}
-
-const TOKEN_KEY = "eventify-auth-token"
-
-function getToken() {
-  return localStorage.getItem(TOKEN_KEY) ?? ""
-}
-
-async function apiFetch(path: string, opts: RequestInit = {}) {
-  const res = await fetch(path, {
-    ...opts,
-    headers: {
-      "Content-Type": "application/json",
-      Authorization: `Bearer ${getToken()}`,
-      ...opts.headers,
-    },
-  })
-  if (!res.ok) throw new Error((await res.json()).error ?? "Request failed")
-  return res.json()
-}
-
-export function SettingsPage() {
-  const [users, setUsers] = useState<MonitorUser[]>([])
-  const [loading, setLoading] = useState(true)
-  const [showForm, setShowForm] = useState(false)
-  const [form, setForm] = useState({ email: "", name: "", role: "developer" as MonitorUser["role"], notifyOnError: true })
-  const [error, setError] = useState("")
-
-  const load = useCallback(async () => {
-    try {
-      setLoading(true)
-      const data = await apiFetch("/api/users")
-      setUsers(data)
-    } catch (e) {
-      setError((e as Error).message)
-    } finally {
-      setLoading(false)
-    }
-  }, [])
-
-  useEffect(() => { load() }, [load])
-
-  const handleAdd = async () => {
-    if (!form.email || !form.name) { setError("Email and name are required"); return }
-    try {
-      setError("")
-      await apiFetch("/api/users", { method: "POST", body: JSON.stringify(form) })
-      setShowForm(false)
-      setForm({ email: "", name: "", role: "developer", notifyOnError: true })
-      load()
-    } catch (e) { setError((e as Error).message) }
-  }
-
-  const handleDelete = async (id: string, name: string) => {
-    if (!confirm(`Remove ${name} from the user list?`)) return
-    try {
-      await apiFetch(`/api/users/${id}`, { method: "DELETE" })
-      load()
-    } catch (e) { setError((e as Error).message) }
-  }
-
-  const toggleNotify = async (id: string) => {
-    const user = users.find(u => u.id === id)
-    if (!user) return
-    setUsers(users.map(u => u.id === id ? { ...u, notifyOnError: !u.notifyOnError } : u))
-    try {
-      await apiFetch(`/api/users/${id}`, {
-        method: "PUT",
-        body: JSON.stringify({ notifyOnError: !user.notifyOnError }),
-      })
-    } catch (e) {
-      load() // revert on error
-      setError((e as Error).message)
-    }
-  }
-
-  const roleIcon = (role: string) =>
-    role === "server-admin"
-      ? <Shield className="size-4 text-amber-500" />
-      : <Code className="size-4 text-blue-500" />
-
-  const roleBadge = (role: string) => (
-    <span className={`inline-flex items-center gap-1 rounded-full px-2.5 py-0.5 text-xs font-medium ${
-      role === "server-admin" ? "bg-amber-100 text-amber-700" : "bg-blue-100 text-blue-700"
-    }`}>
-      {roleIcon(role)}
-      {role === "server-admin" ? "Server Admin" : "Developer"}
-    </span>
-  )
-
-  return (
-    <div className="mx-auto max-w-3xl space-y-6">
-      {/* Header */}
-      <div className="flex items-center justify-between">
-        <div>
-          <h2 className="text-lg font-semibold text-foreground">User Management</h2>
-          <p className="text-sm text-muted-foreground">Manage who can access this dashboard and receive error alerts</p>
-        </div>
-        <button
-          onClick={() => setShowForm(!showForm)}
-          className="inline-flex items-center gap-2 rounded-lg bg-primary px-4 py-2 text-sm font-medium text-primary-foreground hover:bg-primary/90"
-        >
-          <UserPlus className="size-4" />
-          Add User
-        </button>
-      </div>
-
-      {error && (
-        <div className="rounded-lg border border-red-200 bg-red-50 px-4 py-3 text-sm text-red-700">
-          {error}
-          <button onClick={() => setError("")} className="ml-2 font-medium underline">Dismiss</button>
-        </div>
-      )}
-
-      {/* Add User Form */}
-      {showForm && (
-        <div className="rounded-xl border bg-card p-5 space-y-4">
-          <h3 className="text-sm font-semibold text-foreground">New User</h3>
-          <div className="grid grid-cols-2 gap-4">
-            <div>
-              <label className="mb-1 block text-xs font-medium text-muted-foreground">Name</label>
-              <input
-                className="w-full rounded-lg border bg-background px-3 py-2 text-sm focus:border-primary focus:outline-none"
-                placeholder="John Doe"
-                value={form.name}
-                onChange={e => setForm({ ...form, name: e.target.value })}
-              />
-            </div>
-            <div>
-              <label className="mb-1 block text-xs font-medium text-muted-foreground">Email</label>
-              <input
-                className="w-full rounded-lg border bg-background px-3 py-2 text-sm focus:border-primary focus:outline-none"
-                placeholder="john@example.com"
-                value={form.email}
-                onChange={e => setForm({ ...form, email: e.target.value })}
-              />
-            </div>
-            <div>
-              <label className="mb-1 block text-xs font-medium text-muted-foreground">Role</label>
-              <select
-                className="w-full rounded-lg border bg-background px-3 py-2 text-sm focus:border-primary focus:outline-none"
-                value={form.role}
-                onChange={e => setForm({ ...form, role: e.target.value as MonitorUser["role"] })}
-              >
-                <option value="developer">Developer</option>
-                <option value="server-admin">Server Admin</option>
-              </select>
-            </div>
-            <div className="flex items-end">
-              <label className="flex items-center gap-2 text-sm">
-                <input
-                  type="checkbox"
-                  checked={form.notifyOnError}
-                  onChange={e => setForm({ ...form, notifyOnError: e.target.checked })}
-                  className="rounded"
-                />
-                Receive error alerts
-              </label>
-            </div>
-          </div>
-          <div className="flex gap-2">
-            <button onClick={handleAdd} className="inline-flex items-center gap-1 rounded-lg bg-primary px-4 py-2 text-sm font-medium text-primary-foreground hover:bg-primary/90">
-              <Check className="size-4" /> Add
-            </button>
-            <button onClick={() => { setShowForm(false); setError("") }} className="inline-flex items-center gap-1 rounded-lg border px-4 py-2 text-sm font-medium hover:bg-muted">
-              <X className="size-4" /> Cancel
-            </button>
-          </div>
-        </div>
-      )}
-
-      {/* User List */}
-      {loading ? (
-        <div className="flex justify-center py-12">
-          <div className="h-8 w-8 animate-spin rounded-full border-4 border-primary border-t-transparent" />
-        </div>
-      ) : (
-        <div className="rounded-xl border bg-card">
-          <div className="grid grid-cols-[1fr_auto_auto_auto] gap-4 border-b px-5 py-3 text-xs font-semibold uppercase tracking-wider text-muted-foreground">
-            <span>User</span>
-            <span>Role</span>
-            <span>Alerts</span>
-            <span>Actions</span>
-          </div>
-          {users.map(u => (
-            <div key={u.id} className="grid grid-cols-[1fr_auto_auto_auto] items-center gap-4 border-b px-5 py-4 last:border-b-0">
-              <div>
-                <div className="font-medium text-foreground">{u.name}</div>
-                <div className="text-sm text-muted-foreground">{u.email}</div>
-              </div>
-              <div>{roleBadge(u.role)}</div>
-              <div>
-                <button
-                  onClick={() => toggleNotify(u.id)}
-                  className={`flex size-8 items-center justify-center rounded-lg transition-colors ${
-                    u.notifyOnError ? "text-green-600 hover:bg-green-50" : "text-muted-foreground hover:bg-muted"
-                  }`}
-                  title={u.notifyOnError ? "Receiving alerts" : "Alerts disabled"}
-                >
-                  {u.notifyOnError ? <Bell className="size-4" /> : <BellOff className="size-4" />}
-                </button>
-              </div>
-              <div>
-                <button
-                  onClick={() => handleDelete(u.id, u.name)}
-                  className="flex size-8 items-center justify-center rounded-lg text-muted-foreground transition-colors hover:bg-red-50 hover:text-red-600"
-                  title="Remove user"
-                >
-                  <Trash2 className="size-4" />
-                </button>
-              </div>
-            </div>
-          ))}
-          {users.length === 0 && (
-            <div className="px-5 py-12 text-center text-sm text-muted-foreground">
-              No users yet. Add your first user above.
-            </div>
-          )}
-        </div>
-      )}
-    </div>
-  )
-}
diff --git a/client/src/hooks/useNotifications.ts b/client/src/hooks/useNotifications.ts
new file mode 100644
index 0000000..4ef5b32
--- /dev/null
+++ b/client/src/hooks/useNotifications.ts
@@ -0,0 +1,148 @@
+import { useQuery, useMutation, useQueryClient } from "@tanstack/react-query"
+import type {
+  AlertsResponse,
+  ThresholdsConfig,
+  NotificationPreferences,
+  NotificationSummary,
+} from "@/types/notifications"
+
+const TOKEN_KEY = "eventify-auth-token"
+
+function authHeaders(): HeadersInit {
+  const token = localStorage.getItem(TOKEN_KEY)
+  return { Authorization: `Bearer ${token}`, "Content-Type": "application/json" }
+}
+
+async function apiFetch<T>(url: string, options?: RequestInit): Promise<T> {
+  const res = await fetch(url, { ...options, headers: authHeaders() })
+  if (!res.ok) {
+    const err = await res.json().catch(() => ({ error: res.statusText }))
+    throw new Error(err.error ?? `HTTP ${res.status}`)
+  }
+  return res.json() as Promise<T>
+}
+
+// ── Alert list ──
+
+export function useNotifications(page = 1, limit = 20, status = "all") {
+  return useQuery<AlertsResponse>({
+    queryKey: ["notifications", page, limit, status],
+    queryFn: () =>
+      apiFetch<AlertsResponse>(
+        `/api/notifications?page=${page}&limit=${limit}&status=${status}`
+      ),
+    refetchInterval: 30_000,
+  })
+}
+
+// ── Summary (used for sidebar badge) ──
+
+export function useNotificationSummary() {
+  return useQuery<NotificationSummary>({
+    queryKey: ["notifications-summary"],
+    queryFn: () => apiFetch<NotificationSummary>("/api/notifications/summary"),
+    refetchInterval: 30_000,
+  })
+}
+
+// ── Thresholds ──
+
+export function useThresholds() {
+  return useQuery<ThresholdsConfig>({
+    queryKey: ["notifications-thresholds"],
+    queryFn: () => apiFetch<ThresholdsConfig>("/api/notifications/thresholds"),
+  })
+}
+
+export function useUpdateThresholds() {
+  const qc = useQueryClient()
+  return useMutation({
+    mutationFn: (data: ThresholdsConfig) =>
+      apiFetch<ThresholdsConfig>("/api/notifications/thresholds", {
+        method: "PUT",
+        body: JSON.stringify(data),
+      }),
+    onSuccess: () => qc.invalidateQueries({ queryKey: ["notifications-thresholds"] }),
+  })
+}
+
+// ── Preferences ──
+
+export function usePreferences() {
+  return useQuery<NotificationPreferences>({
+    queryKey: ["notifications-preferences"],
+    queryFn: () => apiFetch<NotificationPreferences>("/api/notifications/preferences"),
+  })
+}
+
+export function useUpdatePreferences() {
+  const qc = useQueryClient()
+  return useMutation({
+    mutationFn: (data: NotificationPreferences) =>
+      apiFetch<NotificationPreferences>("/api/notifications/preferences", {
+        method: "PUT",
+        body: JSON.stringify(data),
+      }),
+    onSuccess: () => qc.invalidateQueries({ queryKey: ["notifications-preferences"] }),
+  })
+}
+
+// ── Alert mutations ──
+
+export function useAcknowledgeAlert() {
+  const qc = useQueryClient()
+  return useMutation({
+    mutationFn: (id: string) =>
+      apiFetch(`/api/notifications/${id}/acknowledge`, { method: "PATCH" }),
+    onSuccess: () => {
+      qc.invalidateQueries({ queryKey: ["notifications"] })
+      qc.invalidateQueries({ queryKey: ["notifications-summary"] })
+    },
+  })
+}
+
+export function useDeleteAlert() {
+  const qc = useQueryClient()
+  return useMutation({
+    mutationFn: (id: string) =>
+      apiFetch(`/api/notifications/${id}`, { method: "DELETE" }),
+    onSuccess: () => {
+      qc.invalidateQueries({ queryKey: ["notifications"] })
+      qc.invalidateQueries({ queryKey: ["notifications-summary"] })
+    },
+  })
+}
+
+export function useClearResolved() {
+  const qc = useQueryClient()
+  return useMutation({
+    mutationFn: () =>
+      apiFetch<{ success: boolean; cleared: number }>("/api/notifications/clear", {
+        method: "DELETE",
+      }),
+    onSuccess: () => {
+      qc.invalidateQueries({ queryKey: ["notifications"] })
+      qc.invalidateQueries({ queryKey: ["notifications-summary"] })
+    },
+  })
+}
+
+export function useSendTestEmail() {
+  return useMutation({
+    mutationFn: (email: string) =>
+      apiFetch<{ success: boolean; message: string }>("/api/notifications/test-email", {
+        method: "POST",
+        body: JSON.stringify({ email }),
+      }),
+  })
+}
+
+export function useSendSampleAlerts() {
+  return useMutation({
+    mutationFn: (email: string) =>
+      apiFetch<{ success: boolean; message: string; types: string[] }>("/api/notifications/test-all", {
+        method: "POST",
+        body: JSON.stringify({ email }),
+      }),
+  })
+}
diff --git a/client/src/types/notifications.ts b/client/src/types/notifications.ts
new file mode 100644
index 0000000..a85c24b
--- /dev/null
+++ b/client/src/types/notifications.ts
@@ -0,0 +1,80 @@
+// ─── Client-side Notification Types ───
+
+export type AlertSeverity = 'critical' | 'warning' | 'info';
+
+export type MetricKey =
+  | 'cpu_percent'
+  | 'load_avg_1m'
+  | 'memory_percent'
+  | 'disk_percent'
+  | 'nginx_status'
+  | 'container_stopped'
+  | 'connections_total'
+  | 'connections_per_ip'
+  | 'request_rate'
+  | 'error_rate_5xx';
+
+export interface ThresholdConfig {
+  metric: MetricKey;
+  warning: number;
+  critical: number;
+  enabled: boolean;
+}
+
+export interface ThresholdsConfig {
+  thresholds: ThresholdConfig[];
+  updatedAt: string;
+}
+
+export interface AlertRecord {
+  id: string;
+  metric: MetricKey;
+  severity: AlertSeverity;
+  message: string;
+  value: number | string;
+  threshold: number | string;
+  firedAt: string;
+  resolvedAt: string | null;
+  emailSent: boolean;
+  acknowledged: boolean;
+}
+
+export interface EmailRecipient {
+  email: string;
+  name: string;
+  enabled: boolean;
+}
+
+export interface NotificationPreferences {
+  recipients: EmailRecipient[];
+  cooldownMinutes: number;
+  enabledSeverities: AlertSeverity[];
+  updatedAt: string;
+}
+
+export interface NotificationSummary {
+  activeWarnings: number;
+  activeCriticals: number;
+  unacknowledged: number;
+  total: number;
+}
+
+export interface AlertsResponse {
+  alerts: AlertRecord[];
+  total: number;
+  page: number;
+  limit: number;
+}
+
+export const METRIC_LABELS: Record<MetricKey, string> = {
+  cpu_percent:        'CPU Usage',
+  load_avg_1m:        'Load Average (1m)',
+  memory_percent:     'Memory Usage',
+  disk_percent:       'Disk Usage',
+  nginx_status:       'Nginx Status',
+  container_stopped:  'Container Stopped',
+  connections_total:  'Total Connections',
+  connections_per_ip: 'Connections per IP',
+  request_rate:       'Request Rate',
+  error_rate_5xx:     '5xx Error Rate',
+};
diff --git a/client/src/types/server.ts b/client/src/types/server.ts
index e4b52d1..5b68583 100644
--- a/client/src/types/server.ts
+++ b/client/src/types/server.ts
@@ -43,12 +43,21 @@ export interface NginxStatus {
   checkedAt: string
 }
 
+export interface TrafficInfo {
+  totalConnections: number
+  topIpConnections: number
+  topIp: string
+  requestsPerMinute: number
+  errors5xxPerMinute: number
+}
+
 export interface ServerOverview {
   system: SystemHealth | null
   memory: MemoryStats | null
   disk: DiskStats | null
   docker: ContainerStats[] | null
   nginx: NginxStatus | null
+  traffic: TrafficInfo | null
   errors: Record<string, string>
   timestamp: string
 }
diff --git a/docker-compose.yml b/docker-compose.yml
index 5d7bdf1..a40e629 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -10,7 +10,23 @@ services:
       - SSH_USER=ubuntu
       - SSH_KEY_PATH=/root/.ssh/id_rsa
       - PORT=3002
+      - SMTP_HOST=mail.bshtech.net
+      - SMTP_PORT=587
+      - SMTP_USER=noreply@bshtech.net
+      - SMTP_PASS=Ev3ntifyN0Reply2026
+      - DATA_DIR=/app/data
+      - APP_URL=https://status.eventifyplus.com
     extra_hosts:
       - "host.docker.internal:host-gateway"
     volumes:
       - /home/ubuntu/.ssh/id_rsa:/root/.ssh/id_rsa:ro
+      - monitor-data:/app/data
+    networks:
+      - eventify-net
+
+volumes:
+  monitor-data:
+
+networks:
+  eventify-net:
+    external: true
diff --git a/package-lock.json b/package-lock.json
index bac7f27..b9110ef 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -3016,6 +3016,23 @@
         "undici-types": "~7.18.0"
       }
     },
+    "node_modules/@types/node-cron": {
+      "version": "3.0.11",
+      "resolved": "https://registry.npmjs.org/@types/node-cron/-/node-cron-3.0.11.tgz",
+      "integrity": "sha512-0ikrnug3/IyneSHqCBeslAhlK2aBfYek1fGo4bP4QnZPmiqSGRK+Oy7ZMisLWkesffJvQ1cqAcBnJC+8+nxIAg==",
+      "dev": true,
+      "license": "MIT"
+    },
+    "node_modules/@types/nodemailer": {
+      "version": "6.4.23",
+      "resolved": "https://registry.npmjs.org/@types/nodemailer/-/nodemailer-6.4.23.tgz",
+      "integrity": "sha512-aFV3/NsYFLSx9mbb5gtirBSXJnAlrusoKNuPbxsASWc7vrKLmIrTQRpdcxNcSFL3VW2A2XpeLEavwb2qMi6nlQ==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@types/node": "*"
+      }
+    },
     "node_modules/@types/qs": {
       "version": "6.15.0",
       "resolved": "https://registry.npmjs.org/@types/qs/-/qs-6.15.0.tgz",
@@ -4451,6 +4468,27 @@
         "node": ">= 0.6"
       }
     },
+    "node_modules/node-cron": {
+      "version": "3.0.3",
+      "resolved": "https://registry.npmjs.org/node-cron/-/node-cron-3.0.3.tgz",
+      "integrity": "sha512-dOal67//nohNgYWb+nWmg5dkFdIwDm8EpeGYMekPMrngV3637lqnX0lbUcCtgibHTz6SEz7DAIjKvKDFYCnO1A==",
+      "license": "ISC",
+      "dependencies": {
+        "uuid": "8.3.2"
+      },
+      "engines": {
+        "node": ">=6.0.0"
+      }
+    },
+    "node_modules/nodemailer": {
+      "version": "6.10.1",
+      "resolved": "https://registry.npmjs.org/nodemailer/-/nodemailer-6.10.1.tgz",
+      "integrity": "sha512-Z+iLaBGVaSjbIzQ4pX6XV41HrooLsQ10ZWPUehGmuantvzWoDVBnmsdUcOIDM1t+yPor5pDhVlDESgOMEGxhHA==",
+      "license": "MIT-0",
+      "engines": {
+        "node": ">=6.0.0"
+      }
+    },
     "node_modules/object-assign": {
       "version": "4.1.1",
       "resolved": "https://registry.npmjs.org/object-assign/-/object-assign-4.1.1.tgz",
@@ -5305,6 +5343,15 @@
         "node": ">= 0.4.0"
       }
     },
+    "node_modules/uuid": {
+      "version": "8.3.2",
+      "resolved": "https://registry.npmjs.org/uuid/-/uuid-8.3.2.tgz",
+      "integrity": "sha512-+NYs2QeMWy+GWFOEm9xnn6HCDp0l7QBD7ml8zLUmJ+93Q5NF0NocErnwkTkXVFNiX3/fpC6afS8Dhb/gz7R7eg==",
+      "license": "MIT",
+      "bin": {
+        "uuid": "dist/bin/uuid"
+      }
+    },
     "node_modules/vary": {
       "version": "1.1.2",
       "resolved": "https://registry.npmjs.org/vary/-/vary-1.1.2.tgz",
@@ -5456,12 +5503,16 @@
         "dotenv": "^16.4.0",
         "express": "^4.21.0",
         "jsonwebtoken": "^9.0.3",
+        "node-cron": "^3.0.0",
+        "nodemailer": "^6.9.0",
         "ssh2": "^1.16.0"
       },
       "devDependencies": {
         "@types/cors": "^2.8.17",
         "@types/express": "^5.0.0",
         "@types/jsonwebtoken": "^9.0.10",
+        "@types/node-cron": "^3.0.0",
+        "@types/nodemailer": "^6.4.0",
         "@types/ssh2": "^1.15.0",
         "tsx": "^4.19.0",
         "typescript": "^5.8.0"
diff --git a/server/package.json b/server/package.json
index 0f06a73..08fa059 100644
--- a/server/package.json
+++ b/server/package.json
@@ -12,6 +12,7 @@
     "dotenv": "^16.4.0",
     "express": "^4.21.0",
     "jsonwebtoken": "^9.0.3",
+    "node-cron": "^3.0.0",
     "nodemailer": "^6.9.0",
     "ssh2": "^1.16.0"
   },
@@ -19,6 +20,7 @@
     "@types/cors": "^2.8.17",
     "@types/express": "^5.0.0",
     "@types/jsonwebtoken": "^9.0.10",
+    "@types/node-cron": "^3.0.0",
     "@types/nodemailer": "^6.4.0",
     "@types/ssh2": "^1.15.0",
     "tsx": "^4.19.0",
diff --git a/server/src/config.ts b/server/src/config.ts
index 9505ca4..0295815 100644
--- a/server/src/config.ts
+++ b/server/src/config.ts
@@ -25,4 +25,12 @@ export const config = {
     ],
     jwtSecret: process.env.JWT_SECRET ?? 'eventify-server-monitor-secret-key-change-in-production',
   },
-} as const;
+  smtp: {
+    host: process.env.SMTP_HOST ?? '',
+    port: parseInt(process.env.SMTP_PORT ?? '587', 10),
+    user: process.env.SMTP_USER ?? '',
+    pass: process.env.SMTP_PASS ?? '',
+  },
+  dataDir: process.env.DATA_DIR ?? './data',
+  appUrl: process.env.APP_URL ?? 'https://status.eventifyplus.com',
+};
diff --git a/server/src/index.ts b/server/src/index.ts
index f9b7411..f55cc7f 100644
--- a/server/src/index.ts
+++ b/server/src/index.ts
@@ -2,18 +2,21 @@ import express from 'express';
 import cors from 'cors';
 import { fileURLToPath } from 'url';
 import { dirname, resolve } from 'path';
-import { existsSync } from 'fs';
+import { existsSync, mkdirSync } from 'fs';
 import { config } from './config.js';
 import { healthRouter } from './routes/health.js';
 import { authRouter } from './routes/auth.js';
-import { usersRouter } from './routes/users.js';
+import { notificationRouter } from './routes/notifications.js';
 import { requireAuth } from './middleware/auth.js';
 import { sshManager } from './ssh/client.js';
-import { createNotification } from './services/notifications.js';
+import { startScheduler, stopScheduler } from './services/scheduler.js';
 
 const __filename = fileURLToPath(import.meta.url);
 const __dirname = dirname(__filename);
 
+// Ensure data directory exists
+mkdirSync(config.dataDir, { recursive: true });
+
 const app = express();
 
 // ── Middleware ──
@@ -27,8 +30,8 @@ app.use(express.json());
 
 // ── API Routes ──
 app.use('/api/auth', authRouter);
+app.use('/api/notifications', requireAuth, notificationRouter);
 app.use('/api', requireAuth, healthRouter);
-app.use('/api', requireAuth, usersRouter);
 
 // ── Static file serving for production SPA ──
 const clientDistPath = resolve(__dirname, '../../client/dist');
@@ -45,101 +48,15 @@ if (existsSync(clientDistPath)) {
 const server = app.listen(config.port, () => {
   console.log(`[Server] Listening on http://localhost:${config.port}`);
   console.log(`[Server] SSH target: ${config.ssh.user}@${config.ssh.host}`);
+  startScheduler();
 });
 
-// ── Error monitoring: check health every 60s and alert on issues ──
-const MONITOR_INTERVAL = 60_000;
-let previousErrors: Set<string> = new Set();
-
-async function monitorHealth() {
-  try {
-    const { getSystemInfo } = await import('./services/system.js');
-    const { getDockerInfo } = await import('./services/docker.js');
-    const { getMemoryInfo } = await import('./services/memory.js');
-    const { getDiskInfo } = await import('./services/disk.js');
-
-    const currentErrors: Set<string> = new Set();
-
-    // Check system
-    try {
-      const sys = await getSystemInfo();
-      if (sys.cpuPercent > 90) {
-        const key = 'cpu-high';
-        currentErrors.add(key);
-        if (!previousErrors.has(key)) {
-          await createNotification('warning', 'High CPU Usage', `CPU at ${sys.cpuPercent.toFixed(1)}%`, 'System Monitor');
-        }
-      }
-    } catch (e) {
-      const key = 'system-down';
-      currentErrors.add(key);
-      if (!previousErrors.has(key)) {
-        await createNotification('error', 'System Check Failed', (e as Error).message, 'System Monitor');
-      }
-    }
-
-    // Check memory
-    try {
-      const mem = await getMemoryInfo();
-      if (mem.usedPercent > 90) {
-        const key = 'memory-high';
-        currentErrors.add(key);
-        if (!previousErrors.has(key)) {
-          await createNotification('warning', 'High Memory Usage', `Memory at ${mem.usedPercent.toFixed(1)}%`, 'System Monitor');
-        }
-      }
-    } catch {}
-
-    // Check disk
-    try {
-      const disk = await getDiskInfo();
-      if (disk.usedPercent > 85) {
-        const key = 'disk-high';
-        currentErrors.add(key);
-        if (!previousErrors.has(key)) {
-          await createNotification('warning', 'Disk Space Low', `Disk at ${disk.usedPercent.toFixed(1)}% used`, 'System Monitor');
-        }
-      }
-    } catch {}
-
-    // Check Docker containers
-    try {
-      const containers = await getDockerInfo();
-      for (const c of containers) {
-        if (c.status && !c.status.toLowerCase().includes('up')) {
-          const key = `container-down-${c.name}`;
-          currentErrors.add(key);
-          if (!previousErrors.has(key)) {
-            await createNotification('error', `Container Down: ${c.name}`, `Status: ${c.status}`, 'Docker Monitor');
-          }
-        }
-      }
-    } catch {}
-
-    // Check for recoveries
-    for (const prev of previousErrors) {
-      if (!currentErrors.has(prev)) {
-        await createNotification('recovery', `Recovered: ${prev}`, `The issue "${prev}" has been resolved.`, 'System Monitor');
-      }
-    }
-
-    previousErrors = currentErrors;
-  } catch (err) {
-    console.error('[Monitor] Health check error:', err);
-  }
-}
-
-// Start monitoring after SSH connection is ready (delay 10s)
-setTimeout(() => {
-  monitorHealth();
-  setInterval(monitorHealth, MONITOR_INTERVAL);
-  console.log('[Monitor] Health monitoring started (60s interval)');
-}, 10_000);
-
 // ── Graceful shutdown ──
 async function shutdown(signal: string) {
   console.log(`\n[Server] ${signal} received, shutting down gracefully...`);
 
+  stopScheduler();
+
   server.close(() => {
     console.log('[Server] HTTP server closed');
   });
diff --git a/server/src/routes/health.ts b/server/src/routes/health.ts
index 3e68a66..e284738 100644
--- a/server/src/routes/health.ts
+++ b/server/src/routes/health.ts
@@ -4,6 +4,7 @@ import { getMemoryInfo } from '../services/memory.js';
 import { getDiskInfo } from '../services/disk.js';
 import { getDockerInfo } from '../services/docker.js';
 import { getNginxStatus } from '../services/nginx.js';
+import { getTrafficInfo } from '../services/traffic.js';
 import type { OverviewResponse } from '../types/index.js';
 
 export const healthRouter = Router();
@@ -27,6 +28,7 @@ healthRouter.get('/overview', async (_req, res) => {
     const disk = await safe('disk', getDiskInfo);
     const docker = await safe('docker', getDockerInfo);
     const nginx = await safe('nginx', getNginxStatus);
+    const traffic = await safe('traffic', getTrafficInfo);
 
     const response: OverviewResponse = {
       system,
@@ -34,6 +36,7 @@ healthRouter.get('/overview', async (_req, res) => {
       disk,
       docker,
       nginx,
+      traffic,
       errors,
       timestamp: new Date().toISOString(),
     };
diff --git a/server/src/routes/notifications.ts b/server/src/routes/notifications.ts
new file mode 100644
index 0000000..c6bded1
--- /dev/null
+++ b/server/src/routes/notifications.ts
@@ -0,0 +1,133 @@
+import { Router } from 'express';
+import {
+  getAlerts,
+  getThresholds,
+  saveThresholds,
+  getPreferences,
+  savePreferences,
+  updateAlert,
+  deleteAlert,
+  clearResolvedAlerts,
+} from '../services/store.js';
+import { sendTestEmail, sendSampleAlerts } from '../services/email.js';
+import type { ThresholdsConfig, NotificationPreferences } from '../types/index.js';
+
+export const notificationRouter = Router();
+
+// GET /api/notifications/summary
+notificationRouter.get('/summary', (_req, res) => {
+  const alerts = getAlerts();
+  const active = alerts.filter(a => a.resolvedAt === null);
+  res.json({
+    activeWarnings:   active.filter(a => a.severity === 'warning').length,
+    activeCriticals:  active.filter(a => a.severity === 'critical').length,
+    unacknowledged:   alerts.filter(a => !a.acknowledged).length,
+    total:            alerts.length,
+  });
+});
+
+// GET /api/notifications/thresholds
+notificationRouter.get('/thresholds', (_req, res) => {
+  res.json(getThresholds());
+});
+
+// PUT /api/notifications/thresholds
+notificationRouter.put('/thresholds', (req, res) => {
+  const body = req.body as ThresholdsConfig;
+  if (!body?.thresholds || !Array.isArray(body.thresholds)) {
+    res.status(400).json({ error: 'Invalid thresholds payload' });
+    return;
+  }
+  saveThresholds(body);
+  res.json(getThresholds());
+});
+
+// GET /api/notifications/preferences
+notificationRouter.get('/preferences', (_req, res) => {
+  res.json(getPreferences());
+});
+
+// PUT /api/notifications/preferences
+notificationRouter.put('/preferences', (req, res) => {
+  const body = req.body as NotificationPreferences;
+  if (!body?.recipients || !Array.isArray(body.recipients)) {
+    res.status(400).json({ error: 'Invalid preferences payload' });
+    return;
+  }
+  savePreferences(body);
+  res.json(getPreferences());
+});
+
+// POST /api/notifications/test-email
+notificationRouter.post('/test-email', async (req, res) => {
+  const { email } = req.body as { email?: string };
+  if (!email) {
+    res.status(400).json({ error: 'email is required' });
+    return;
+  }
+  try {
+    await sendTestEmail(email);
+    res.json({ success: true, message: `Test email sent to ${email}` });
+  } catch (err) {
+    res.status(500).json({ error: (err as Error).message });
+  }
+});
+
+// POST /api/notifications/test-all — send sample emails for every alert type
+notificationRouter.post('/test-all', async (req, res) => {
+  const { email } = req.body as { email?: string };
+  if (!email) {
+    res.status(400).json({ error: 'email is required' });
+    return;
+  }
+  try {
+    const result = await sendSampleAlerts(email);
+    res.json({ success: true, message: `Sent ${result.sent.length} sample emails to ${email}`, types: result.sent });
+  } catch (err) {
+    res.status(500).json({ error: (err as Error).message });
+  }
+});
+
+// DELETE /api/notifications/clear
+notificationRouter.delete('/clear', (_req, res) => {
+  const count = clearResolvedAlerts();
+  res.json({ success: true, cleared: count });
+});
+
+// GET /api/notifications — list with filters
+notificationRouter.get('/', (req, res) => {
+  const page   = Math.max(1, parseInt(String(req.query.page  ?? '1'),  10));
+  const limit  = Math.min(100, Math.max(1, parseInt(String(req.query.limit ?? '20'), 10)));
+  const status = String(req.query.status ?? 'all');
+
+  let alerts = getAlerts();
+
+  if (status === 'active')   alerts = alerts.filter(a => a.resolvedAt === null);
+  if (status === 'resolved') alerts = alerts.filter(a => a.resolvedAt !== null);
+
+  const total = alerts.length;
+  const start = (page - 1) * limit;
+  const items = alerts.slice(start, start + limit);
+
+  res.json({ alerts: items, total, page, limit });
+});
+
+// PATCH /api/notifications/:id/acknowledge
+notificationRouter.patch('/:id/acknowledge', (req, res) => {
+  const updated = updateAlert(req.params.id, { acknowledged: true });
+  if (!updated) {
+    res.status(404).json({ error: 'Alert not found' });
+    return;
+  }
+  res.json(updated);
+});
+
+// DELETE /api/notifications/:id
+notificationRouter.delete('/:id', (req, res) => {
+  const ok = deleteAlert(req.params.id);
+  if (!ok) {
+    res.status(404).json({ error: 'Alert not found' });
+    return;
+  }
+  res.json({ success: true });
+});
diff --git a/server/src/services/alertEngine.ts b/server/src/services/alertEngine.ts
new file mode 100644
index 0000000..8bd135f
--- /dev/null
+++ b/server/src/services/alertEngine.ts
@@ -0,0 +1,245 @@
+import { randomUUID } from 'crypto';
+import { getThresholds, getPreferences, addAlert, getActiveAlerts, updateAlert } from './store.js';
+import { sendAlertEmail, sendRecoveryEmail } from './email.js';
+import type { OverviewResponse } from '../types/index.js';
+import type { AlertRecord, AlertSeverity, MetricKey } from '../types/notifications.js';
+
+// In-memory cooldown map: "metric:severity" → last fired timestamp (ms)
+const cooldownMap = new Map<string, number>();
+
+function isCooledDown(metric: MetricKey, severity: AlertSeverity, cooldownMs: number): boolean {
+  const key = `${metric}:${severity}`;
+  const last = cooldownMap.get(key);
+  if (!last) return true;
+  return Date.now() - last >= cooldownMs;
+}
+
+function stampCooldown(metric: MetricKey, severity: AlertSeverity): void {
+  cooldownMap.set(`${metric}:${severity}`, Date.now());
+}
+
+function createAlert(
+  metric: MetricKey,
+  severity: AlertSeverity,
+  message: string,
+  value: number | string,
+  threshold: number | string
+): AlertRecord {
+  return {
+    id: randomUUID(),
+    metric,
+    severity,
+    message,
+    value,
+    threshold,
+    firedAt: new Date().toISOString(),
+    resolvedAt: null,
+    emailSent: false,
+    acknowledged: false,
+  };
+}
+
+export async function evaluateMetrics(overview: OverviewResponse): Promise<void> {
+  const { thresholds } = getThresholds();
+  const prefs = getPreferences();
+  const cooldownMs = prefs.cooldownMinutes * 60_000;
+  const newAlerts: AlertRecord[] = [];
+
+  for (const t of thresholds) {
+    if (!t.enabled) continue;
+
+    // ── Extract metric value ──
+    let value: number | string | null = null;
+
+    switch (t.metric) {
+      case 'cpu_percent':
+        value = overview.system?.cpuPercent ?? null;
+        break;
+      case 'load_avg_1m':
+        value = overview.system?.loadAvg?.[0] ?? null;
+        break;
+      case 'memory_percent':
+        value = overview.memory?.usedPercent ?? null;
+        break;
+      case 'disk_percent':
+        value = overview.disk?.usedPercent ?? null;
+        break;
+      case 'nginx_status':
+        value = overview.nginx?.status !== 'active' ? 1 : 0;
+        break;
+      case 'container_stopped': {
+        const stopped = (overview.docker ?? []).filter(
+          c => !c.status.toLowerCase().includes('up')
+        ).length;
+        value = stopped;
+        break;
+      }
+      case 'connections_total':
+        value = overview.traffic?.totalConnections ?? null;
+        break;
+      case 'connections_per_ip':
+        value = overview.traffic?.topIpConnections ?? null;
+        break;
+      case 'request_rate':
+        value = overview.traffic?.requestsPerMinute ?? null;
+        break;
+      case 'error_rate_5xx':
+        value = overview.traffic?.errors5xxPerMinute ?? null;
+        break;
+    }
+
+    // Metric unreachable
+    if (value === null) {
+      if (isCooledDown(t.metric, 'info', cooldownMs)) {
+        const alert = createAlert(
+          t.metric, 'info',
+          `Metric "${t.metric}" could not be fetched`,
+          'N/A', 'N/A'
+        );
+        addAlert(alert);
+        newAlerts.push(alert);
+        stampCooldown(t.metric, 'info');
+      }
+      continue;
+    }
+
+    // ── Numeric threshold checks ──
+    if (t.metric === 'nginx_status') {
+      // Boolean: fires if nginx is not active
+      if (value === 1) {
+        const nginxStatus = overview.nginx?.status ?? 'unknown';
+        if (isCooledDown(t.metric, 'critical', cooldownMs)) {
+          // Resolve any existing warning first
+          resolveMetricAlerts(t.metric, 'warning', newAlerts);
+          const alert = createAlert(
+            t.metric, 'critical',
+            `Nginx is ${nginxStatus}`,
+            nginxStatus, 'active'
+          );
+          addAlert(alert);
+          newAlerts.push(alert);
+          stampCooldown(t.metric, 'critical');
+        }
+      } else {
+        resolveRecoveredAlerts(t.metric, newAlerts, prefs.recipients);
+      }
+      continue;
+    }
+
+    if (t.metric === 'container_stopped') {
+      if ((value as number) > 0) {
+        const names = (overview.docker ?? [])
+          .filter(c => !c.status.toLowerCase().includes('up'))
+          .map(c => c.name)
+          .join(', ');
+        if (isCooledDown(t.metric, 'warning', cooldownMs)) {
+          const alert = createAlert(
+            t.metric, 'warning',
+            `${value} container(s) not running: ${names}`,
+            `${value} stopped`, '0 stopped'
+          );
+          addAlert(alert);
+          newAlerts.push(alert);
+          stampCooldown(t.metric, 'warning');
+        }
+      } else {
+        resolveRecoveredAlerts(t.metric, newAlerts, prefs.recipients);
+      }
+      continue;
+    }
+
+    const numVal = value as number;
+
+    // Build context-rich messages for traffic metrics
+    function buildMessage(severity: 'warning' | 'critical'): string {
+      const level = severity === 'critical' ? 'critically high' : 'high';
+      switch (t.metric) {
+        case 'connections_total':
+          return `${numVal} active TCP connections — potential DDoS or traffic spike (${level})`;
+        case 'connections_per_ip': {
+          const ip = overview.traffic?.topIp ?? 'unknown';
+          return `Single IP (${ip}) has ${numVal} connections — possible DDoS attack (${level})`;
+        }
+        case 'request_rate':
+          return `${numVal} HTTP requests/min — abnormally high API call volume (${level})`;
+        case 'error_rate_5xx':
+          return `${numVal} server errors (5xx) in the last minute — service degradation (${level})`;
+        default:
+          return `${t.metric.replace(/_/g, ' ')} is ${level} at ${numVal.toFixed(1)}`;
+      }
+    }
+
+    if (numVal >= t.critical) {
+      // Escalate: resolve active warning first
+      resolveMetricAlerts(t.metric, 'warning', newAlerts);
+      if (isCooledDown(t.metric, 'critical', cooldownMs)) {
+        const alert = createAlert(
+          t.metric, 'critical',
+          buildMessage('critical'),
+          parseFloat(numVal.toFixed(2)), t.critical
+        );
+        addAlert(alert);
+        newAlerts.push(alert);
+        stampCooldown(t.metric, 'critical');
+      }
+    } else if (numVal >= t.warning) {
+      if (isCooledDown(t.metric, 'warning', cooldownMs)) {
+        const alert = createAlert(
+          t.metric, 'warning',
+          buildMessage('warning'),
+          parseFloat(numVal.toFixed(2)), t.warning
+        );
+        addAlert(alert);
+        newAlerts.push(alert);
+        stampCooldown(t.metric, 'warning');
+      }
+    } else {
+      // Value back to normal — resolve any active alerts
+      resolveRecoveredAlerts(t.metric, newAlerts, prefs.recipients);
+    }
+  }
+
+  // Send emails for new alerts
+  for (const alert of newAlerts) {
+    if (!prefs.enabledSeverities.includes(alert.severity)) continue;
+    const enabledRecipients = prefs.recipients.filter(r => r.enabled);
+    if (!enabledRecipients.length) continue;
+    try {
+      await sendAlertEmail(alert, enabledRecipients);
+      updateAlert(alert.id, { emailSent: true });
+    } catch (err) {
+      console.error(`[AlertEngine] Failed to send email for alert ${alert.id}:`, (err as Error).message);
+    }
+  }
+
+  if (newAlerts.length > 0) {
+    console.log(`[AlertEngine] ${newAlerts.length} new alert(s) fired.`);
+  }
+}
+
+function resolveMetricAlerts(
+  metric: MetricKey,
+  severity: AlertSeverity,
+  _newAlerts: AlertRecord[]
+): void {
+  const active = getActiveAlerts(metric).filter(a => a.severity === severity);
+  for (const a of active) {
+    updateAlert(a.id, { resolvedAt: new Date().toISOString() });
+  }
+}
+
+function resolveRecoveredAlerts(
+  metric: MetricKey,
+  _newAlerts: AlertRecord[],
+  recipients: { email: string; name: string; enabled: boolean }[]
+): void {
+  const active = getActiveAlerts(metric);
+  for (const a of active) {
+    const resolved = updateAlert(a.id, { resolvedAt: new Date().toISOString() });
+    if (resolved) {
+      sendRecoveryEmail(resolved, recipients.filter(r => r.enabled)).catch((err: Error) =>
+        console.error(`[AlertEngine] Recovery email failed:`, err.message)
+      );
+    }
+  }
+}
diff --git a/server/src/services/email.ts b/server/src/services/email.ts
new file mode 100644
index 0000000..89bce4d
--- /dev/null
+++ b/server/src/services/email.ts
@@ -0,0 +1,633 @@
+import nodemailer from 'nodemailer';
+import { config } from '../config.js';
+import type { AlertRecord, EmailRecipient } from '../types/index.js';
+
+function createTransporter() {
+  return nodemailer.createTransport({
+    host: config.smtp.host,
+    port: config.smtp.port,
+    secure: false,
+    auth: {
+      user: config.smtp.user,
+      pass: config.smtp.pass,
+    },
+    tls: { rejectUnauthorized: false },
+  });
+}
+
+const METRIC_LABELS: Record<string, string> = {
+  cpu_percent:        'CPU Usage',
+  load_avg_1m:        'Load Average (1m)',
+  memory_percent:     'Memory Usage',
+  disk_percent:       'Disk Usage',
+  nginx_status:       'Nginx Status',
+  container_stopped:  'Container Status',
+  connections_total:  'Total Connections',
+  connections_per_ip: 'Connections per IP',
+  request_rate:       'Request Rate',
+  error_rate_5xx:     '5xx Error Rate',
+};
+
+// ── Severity theme config ──
+interface SeverityTheme {
+  gradient: string;
+  badgeBg: string;
+  badgeText: string;
+  accentColor: string;
+  icon: string;
+  label: string;
+}
+
+const SEVERITY_THEMES: Record<string, SeverityTheme> = {
+  critical: {
+    gradient: 'linear-gradient(135deg, #dc2626 0%, #991b1b 100%)',
+    badgeBg: '#fef2f2',
+    badgeText: '#dc2626',
+    accentColor: '#dc2626',
+    icon: '&#9888;',  // ⚠
+    label: 'CRITICAL',
+  },
+  warning: {
+    gradient: 'linear-gradient(135deg, #f59e0b 0%, #d97706 100%)',
+    badgeBg: '#fffbeb',
+    badgeText: '#d97706',
+    accentColor: '#d97706',
+    icon: '&#9888;',  // ⚠
+    label: 'WARNING',
+  },
+  info: {
+    gradient: 'linear-gradient(135deg, #3b82f6 0%, #1d4ed8 100%)',
+    badgeBg: '#eff6ff',
+    badgeText: '#2563eb',
+    accentColor: '#2563eb',
+    icon: '&#8505;',  // ℹ
+    label: 'INFO',
+  },
+};
+
+const RECOVERY_THEME = {
+  gradient: 'linear-gradient(135deg, #22c55e 0%, #15803d 100%)',
+  badgeBg: '#f0fdf4',
+  badgeText: '#16a34a',
+  accentColor: '#16a34a',
+  icon: '&#10004;', // ✔
+  label: 'RESOLVED',
+};
+
+// ── Shared layout wrapper ──
+function emailWrapper(content: string): string {
+  return `<!DOCTYPE html>
+<html lang="en">
+<head>
+  <meta charset="utf-8">
+  <meta name="viewport" content="width=device-width,initial-scale=1">
+  <meta name="color-scheme" content="light">
+  <!--[if mso]><noscript><xml><o:OfficeDocumentSettings><o:AllowPNG/><o:PixelsPerInch>96</o:PixelsPerInch></o:OfficeDocumentSettings></xml></noscript><![endif]-->
+</head>
+<body style="margin:0;padding:0;background-color:#f1f5f9;font-family:-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,'Helvetica Neue',Arial,sans-serif;-webkit-font-smoothing:antialiased;">
+  <table role="presentation" width="100%" cellpadding="0" cellspacing="0" style="background-color:#f1f5f9;">
+    <tr>
+      <td align="center" style="padding:40px 16px;">
+        <table role="presentation" width="560" cellpadding="0" cellspacing="0" style="max-width:560px;width:100%;">
+          ${content}
+          <!-- Footer -->
+          <tr>
+            <td style="padding:24px 0 0;">
+              <table role="presentation" width="100%" cellpadding="0" cellspacing="0">
+                <tr>
+                  <td align="center" style="padding:16px 24px;border-top:1px solid #e2e8f0;">
+                    <table role="presentation" cellpadding="0" cellspacing="0">
+                      <tr>
+                        <td style="padding-right:8px;vertical-align:middle;">
+                          <div style="width:24px;height:24px;background:linear-gradient(135deg,#6366f1 0%,#4f46e5 100%);border-radius:6px;text-align:center;line-height:24px;color:#fff;font-size:13px;font-weight:700;">E</div>
+                        </td>
+                        <td style="vertical-align:middle;">
+                          <span style="font-size:13px;font-weight:600;color:#475569;">Eventify Server Monitor</span>
+                        </td>
+                      </tr>
+                    </table>
+                    <p style="margin:8px 0 0;font-size:12px;color:#94a3b8;">
+                      <a href="${config.appUrl}" style="color:#6366f1;text-decoration:none;">status.eventifyplus.com</a>
+                      &nbsp;&middot;&nbsp; Automated alert — do not reply
+                    </p>
+                  </td>
+                </tr>
+              </table>
+            </td>
+          </tr>
+        </table>
+      </td>
+    </tr>
+  </table>
+</body>
+</html>`;
+}
+
+// ── Alert email (critical / warning / info) ──
+function buildAlertHtml(alert: AlertRecord): string {
+  const theme = SEVERITY_THEMES[alert.severity] ?? SEVERITY_THEMES.info;
+  const label = METRIC_LABELS[alert.metric] ?? alert.metric;
+  const firedAt = new Date(alert.firedAt).toLocaleString('en-IN', { timeZone: 'Asia/Kolkata' });
+
+  const content = `
+          <!-- Header with gradient -->
+          <tr>
+            <td style="background:${theme.gradient};padding:32px 32px 28px;border-radius:12px 12px 0 0;">
+              <table role="presentation" width="100%" cellpadding="0" cellspacing="0">
+                <tr>
+                  <td>
+                    <!-- Severity badge -->
+                    <div style="display:inline-block;background:rgba(255,255,255,0.2);border-radius:20px;padding:4px 14px 4px 10px;margin-bottom:16px;">
+                      <span style="color:#fff;font-size:12px;font-weight:700;letter-spacing:1.5px;">${theme.icon}&nbsp; ${theme.label} ALERT</span>
+                    </div>
+                    <h1 style="margin:0 0 6px;color:#ffffff;font-size:22px;font-weight:700;line-height:1.3;">
+                      ${label} Threshold Breached
+                    </h1>
+                    <p style="margin:0;color:rgba(255,255,255,0.85);font-size:14px;">
+                      Detected at ${firedAt} IST
+                    </p>
+                  </td>
+                </tr>
+              </table>
+            </td>
+          </tr>
+
+          <!-- Body card -->
+          <tr>
+            <td style="background:#ffffff;padding:0;border-left:1px solid #e2e8f0;border-right:1px solid #e2e8f0;">
+              <!-- Metric value highlight -->
+              <table role="presentation" width="100%" cellpadding="0" cellspacing="0">
+                <tr>
+                  <td style="padding:28px 32px 20px;">
+                    <table role="presentation" width="100%" cellpadding="0" cellspacing="0" style="background:${theme.badgeBg};border-radius:10px;border:1px solid ${theme.accentColor}20;">
+                      <tr>
+                        <td style="padding:20px 24px;">
+                          <table role="presentation" width="100%" cellpadding="0" cellspacing="0">
+                            <tr>
+                              <td width="50%">
+                                <p style="margin:0 0 4px;font-size:11px;text-transform:uppercase;letter-spacing:1px;color:#64748b;font-weight:600;">Current Value</p>
+                                <p style="margin:0;font-size:28px;font-weight:800;color:${theme.accentColor};line-height:1.2;">${alert.value}</p>
+                              </td>
+                              <td width="50%" style="text-align:right;">
+                                <p style="margin:0 0 4px;font-size:11px;text-transform:uppercase;letter-spacing:1px;color:#64748b;font-weight:600;">Threshold</p>
+                                <p style="margin:0;font-size:28px;font-weight:800;color:#334155;line-height:1.2;">${alert.threshold}</p>
+                              </td>
+                            </tr>
+                          </table>
+                        </td>
+                      </tr>
+                    </table>
+                  </td>
+                </tr>
+              </table>
+
+              <!-- Details -->
+              <table role="presentation" width="100%" cellpadding="0" cellspacing="0">
+                <tr>
+                  <td style="padding:0 32px 28px;">
+                    <table role="presentation" width="100%" cellpadding="0" cellspacing="0" style="border-collapse:separate;border-spacing:0;">
+                      <!-- Metric -->
+                      <tr>
+                        <td style="padding:12px 0;border-bottom:1px solid #f1f5f9;" width="140">
+                          <span style="font-size:13px;color:#64748b;font-weight:500;">Metric</span>
+                        </td>
+                        <td style="padding:12px 0;border-bottom:1px solid #f1f5f9;">
+                          <span style="font-size:14px;color:#0f172a;font-weight:600;">${label}</span>
+                        </td>
+                      </tr>
+                      <!-- Severity -->
+                      <tr>
+                        <td style="padding:12px 0;border-bottom:1px solid #f1f5f9;">
+                          <span style="font-size:13px;color:#64748b;font-weight:500;">Severity</span>
+                        </td>
+                        <td style="padding:12px 0;border-bottom:1px solid #f1f5f9;">
+                          <span style="display:inline-block;background:${theme.badgeBg};color:${theme.badgeText};font-size:12px;font-weight:700;padding:3px 10px;border-radius:12px;border:1px solid ${theme.accentColor}30;text-transform:uppercase;letter-spacing:0.5px;">${alert.severity}</span>
+                        </td>
+                      </tr>
+                      <!-- Message -->
+                      <tr>
+                        <td style="padding:12px 0;" valign="top">
+                          <span style="font-size:13px;color:#64748b;font-weight:500;">Details</span>
+                        </td>
+                        <td style="padding:12px 0;">
+                          <span style="font-size:14px;color:#334155;line-height:1.5;">${alert.message}</span>
+                        </td>
+                      </tr>
+                    </table>
+                  </td>
+                </tr>
+              </table>
+
+              <!-- CTA Button -->
+              <table role="presentation" width="100%" cellpadding="0" cellspacing="0">
+                <tr>
+                  <td style="padding:0 32px 32px;">
+                    <table role="presentation" cellpadding="0" cellspacing="0">
+                      <tr>
+                        <td style="background:${theme.gradient};border-radius:8px;">
+                          <a href="${config.appUrl}" target="_blank" style="display:inline-block;padding:12px 28px;color:#ffffff;text-decoration:none;font-size:14px;font-weight:600;letter-spacing:0.3px;">
+                            View Dashboard &rarr;
+                          </a>
+                        </td>
+                      </tr>
+                    </table>
+                  </td>
+                </tr>
+              </table>
+            </td>
+          </tr>
+
+          <!-- Bottom border radius -->
+          <tr>
+            <td style="background:#ffffff;height:4px;border-radius:0 0 12px 12px;border-left:1px solid #e2e8f0;border-right:1px solid #e2e8f0;border-bottom:1px solid #e2e8f0;"></td>
+          </tr>`;
+
+  return emailWrapper(content);
+}
+
+// ── Recovery email ──
+function buildRecoveryHtml(alert: AlertRecord): string {
+  const theme = RECOVERY_THEME;
+  const label = METRIC_LABELS[alert.metric] ?? alert.metric;
+  const firedAt = new Date(alert.firedAt).toLocaleString('en-IN', { timeZone: 'Asia/Kolkata' });
+  const resolvedAt = alert.resolvedAt
+    ? new Date(alert.resolvedAt).toLocaleString('en-IN', { timeZone: 'Asia/Kolkata' })
+    : 'N/A';
+
+  const content = `
+          <!-- Header with gradient -->
+          <tr>
+            <td style="background:${theme.gradient};padding:32px 32px 28px;border-radius:12px 12px 0 0;">
+              <table role="presentation" width="100%" cellpadding="0" cellspacing="0">
+                <tr>
+                  <td>
+                    <div style="display:inline-block;background:rgba(255,255,255,0.2);border-radius:20px;padding:4px 14px 4px 10px;margin-bottom:16px;">
+                      <span style="color:#fff;font-size:12px;font-weight:700;letter-spacing:1.5px;">${theme.icon}&nbsp; ${theme.label}</span>
+                    </div>
+                    <h1 style="margin:0 0 6px;color:#ffffff;font-size:22px;font-weight:700;line-height:1.3;">
+                      ${label} — Back to Normal
+                    </h1>
+                    <p style="margin:0;color:rgba(255,255,255,0.85);font-size:14px;">
+                      Resolved at ${resolvedAt} IST
+                    </p>
+                  </td>
+                </tr>
+              </table>
+            </td>
+          </tr>
+
+          <!-- Body card -->
+          <tr>
+            <td style="background:#ffffff;padding:0;border-left:1px solid #e2e8f0;border-right:1px solid #e2e8f0;">
+              <!-- Recovery status highlight -->
+              <table role="presentation" width="100%" cellpadding="0" cellspacing="0">
+                <tr>
+                  <td style="padding:28px 32px 20px;">
+                    <table role="presentation" width="100%" cellpadding="0" cellspacing="0" style="background:${theme.badgeBg};border-radius:10px;border:1px solid ${theme.accentColor}20;">
+                      <tr>
+                        <td style="padding:20px 24px;text-align:center;">
+                          <div style="font-size:36px;line-height:1;">&#10003;</div>
+                          <p style="margin:8px 0 0;font-size:18px;font-weight:700;color:${theme.accentColor};">All Clear</p>
+                          <p style="margin:4px 0 0;font-size:13px;color:#64748b;">The metric has returned to acceptable levels</p>
+                        </td>
+                      </tr>
+                    </table>
+                  </td>
+                </tr>
+              </table>
+
+              <!-- Timeline -->
+              <table role="presentation" width="100%" cellpadding="0" cellspacing="0">
+                <tr>
+                  <td style="padding:0 32px 28px;">
+                    <table role="presentation" width="100%" cellpadding="0" cellspacing="0">
+                      <tr>
+                        <td style="padding:12px 0;border-bottom:1px solid #f1f5f9;" width="140">
+                          <span style="font-size:13px;color:#64748b;font-weight:500;">Metric</span>
+                        </td>
+                        <td style="padding:12px 0;border-bottom:1px solid #f1f5f9;">
+                          <span style="font-size:14px;color:#0f172a;font-weight:600;">${label}</span>
+                        </td>
+                      </tr>
+                      <tr>
+                        <td style="padding:12px 0;border-bottom:1px solid #f1f5f9;">
+                          <span style="font-size:13px;color:#64748b;font-weight:500;">Alert Fired</span>
+                        </td>
+                        <td style="padding:12px 0;border-bottom:1px solid #f1f5f9;">
+                          <span style="font-size:14px;color:#334155;">${firedAt} IST</span>
+                        </td>
+                      </tr>
+                      <tr>
+                        <td style="padding:12px 0;border-bottom:1px solid #f1f5f9;">
+                          <span style="font-size:13px;color:#64748b;font-weight:500;">Resolved</span>
+                        </td>
+                        <td style="padding:12px 0;border-bottom:1px solid #f1f5f9;">
+                          <span style="font-size:14px;color:${theme.accentColor};font-weight:600;">${resolvedAt} IST</span>
+                        </td>
+                      </tr>
+                      <tr>
+                        <td style="padding:12px 0;">
+                          <span style="font-size:13px;color:#64748b;font-weight:500;">Previous Alert</span>
+                        </td>
+                        <td style="padding:12px 0;">
+                          <span style="font-size:14px;color:#334155;">${alert.message}</span>
+                        </td>
+                      </tr>
+                    </table>
+                  </td>
+                </tr>
+              </table>
+
+              <!-- CTA Button -->
+              <table role="presentation" width="100%" cellpadding="0" cellspacing="0">
+                <tr>
+                  <td style="padding:0 32px 32px;">
+                    <table role="presentation" cellpadding="0" cellspacing="0">
+                      <tr>
+                        <td style="background:${theme.gradient};border-radius:8px;">
+                          <a href="${config.appUrl}" target="_blank" style="display:inline-block;padding:12px 28px;color:#ffffff;text-decoration:none;font-size:14px;font-weight:600;letter-spacing:0.3px;">
+                            View Dashboard &rarr;
+                          </a>
+                        </td>
+                      </tr>
+                    </table>
+                  </td>
+                </tr>
+              </table>
+            </td>
+          </tr>
+
+          <!-- Bottom border radius -->
+          <tr>
+            <td style="background:#ffffff;height:4px;border-radius:0 0 12px 12px;border-left:1px solid #e2e8f0;border-right:1px solid #e2e8f0;border-bottom:1px solid #e2e8f0;"></td>
+          </tr>`;
+
+  return emailWrapper(content);
+}
+
+// ── Test email (basic SMTP check) ──
+function buildTestHtml(): string {
+  const content = `
+          <!-- Header -->
+          <tr>
+            <td style="background:linear-gradient(135deg,#6366f1 0%,#4f46e5 100%);padding:32px 32px 28px;border-radius:12px 12px 0 0;">
+              <table role="presentation" width="100%" cellpadding="0" cellspacing="0">
+                <tr>
+                  <td>
+                    <div style="display:inline-block;background:rgba(255,255,255,0.2);border-radius:20px;padding:4px 14px 4px 10px;margin-bottom:16px;">
+                      <span style="color:#fff;font-size:12px;font-weight:700;letter-spacing:1.5px;">&#9889;&nbsp; SMTP TEST</span>
+                    </div>
+                    <h1 style="margin:0 0 6px;color:#ffffff;font-size:22px;font-weight:700;">
+                      Connection Verified
+                    </h1>
+                    <p style="margin:0;color:rgba(255,255,255,0.85);font-size:14px;">
+                      Your SMTP settings are configured correctly
+                    </p>
+                  </td>
+                </tr>
+              </table>
+            </td>
+          </tr>
+
+          <!-- Body -->
+          <tr>
+            <td style="background:#ffffff;padding:28px 32px 32px;border-left:1px solid #e2e8f0;border-right:1px solid #e2e8f0;">
+              <table role="presentation" width="100%" cellpadding="0" cellspacing="0" style="background:#f0fdf4;border-radius:10px;border:1px solid #bbf7d0;">
+                <tr>
+                  <td style="padding:20px 24px;text-align:center;">
+                    <div style="font-size:36px;line-height:1;">&#10003;</div>
+                    <p style="margin:8px 0 0;font-size:16px;font-weight:700;color:#16a34a;">SMTP is Working</p>
+                    <p style="margin:6px 0 0;font-size:13px;color:#64748b;line-height:1.5;">
+                      This confirms that Eventify Server Monitor can send<br>alert and recovery emails through your mail server.
+                    </p>
+                  </td>
+                </tr>
+              </table>
+
+              <table role="presentation" width="100%" cellpadding="0" cellspacing="0" style="margin-top:20px;">
+                <tr>
+                  <td>
+                    <table role="presentation" cellpadding="0" cellspacing="0">
+                      <tr>
+                        <td style="background:linear-gradient(135deg,#6366f1 0%,#4f46e5 100%);border-radius:8px;">
+                          <a href="${config.appUrl}" target="_blank" style="display:inline-block;padding:12px 28px;color:#ffffff;text-decoration:none;font-size:14px;font-weight:600;letter-spacing:0.3px;">
+                            View Dashboard &rarr;
+                          </a>
+                        </td>
+                      </tr>
+                    </table>
+                  </td>
+                </tr>
+              </table>
+            </td>
+          </tr>
+
+          <!-- Bottom border radius -->
+          <tr>
+            <td style="background:#ffffff;height:4px;border-radius:0 0 12px 12px;border-left:1px solid #e2e8f0;border-right:1px solid #e2e8f0;border-bottom:1px solid #e2e8f0;"></td>
+          </tr>`;
+
+  return emailWrapper(content);
+}
+
+// ── Public send functions ──
+
+export async function sendAlertEmail(alert: AlertRecord, recipients: EmailRecipient[]): Promise<void> {
+  const enabled = recipients.filter(r => r.enabled);
+  if (!enabled.length || !config.smtp.host) return;
+
+  const transporter = createTransporter();
+  const label = METRIC_LABELS[alert.metric] ?? alert.metric;
+  const subject = `[${alert.severity.toUpperCase()}] ${label} alert — Eventify Server`;
+
+  await transporter.sendMail({
+    from: `"Eventify Monitor" <${config.smtp.user}>`,
+    to: enabled.map(r => `"${r.name}" <${r.email}>`).join(', '),
+    subject,
+    html: buildAlertHtml(alert),
+  });
+}
+
+export async function sendRecoveryEmail(alert: AlertRecord, recipients: EmailRecipient[]): Promise<void> {
+  const enabled = recipients.filter(r => r.enabled);
+  if (!enabled.length || !config.smtp.host) return;
+
+  const transporter = createTransporter();
+  const label = METRIC_LABELS[alert.metric] ?? alert.metric;
+
+  await transporter.sendMail({
+    from: `"Eventify Monitor" <${config.smtp.user}>`,
+    to: enabled.map(r => `"${r.name}" <${r.email}>`).join(', '),
+    subject: `[RESOLVED] ${label} — Eventify Server`,
+    html: buildRecoveryHtml(alert),
+  });
+}
+
+export async function sendTestEmail(to: string): Promise<void> {
+  if (!config.smtp.host) throw new Error('SMTP not configured');
+  const transporter = createTransporter();
+  await transporter.sendMail({
+    from: `"Eventify Monitor" <${config.smtp.user}>`,
+    to,
+    subject: 'SMTP Test — Eventify Server Monitor',
+    html: buildTestHtml(),
+  });
+}
+
+// ── Send sample emails for every alert type ──
+export async function sendSampleAlerts(to: string): Promise<{ sent: string[] }> {
+  if (!config.smtp.host) throw new Error('SMTP not configured');
+  const transporter = createTransporter();
+  const from = `"Eventify Monitor" <${config.smtp.user}>`;
+  const now = new Date().toISOString();
+  const sent: string[] = [];
+
+  // 1. Critical alert
+  const criticalAlert: AlertRecord = {
+    id: 'sample-critical',
+    metric: 'cpu_percent',
+    severity: 'critical',
+    message: 'CPU utilization is critically high at 97.2% — sustained for over 5 minutes',
+    value: 97.2,
+    threshold: 95,
+    firedAt: now,
+    resolvedAt: null,
+    emailSent: true,
+    acknowledged: false,
+  };
+  await transporter.sendMail({
+    from,
+    to,
+    subject: '[CRITICAL] CPU Usage alert — Eventify Server (Sample)',
+    html: buildAlertHtml(criticalAlert),
+  });
+  sent.push('critical');
+
+  // 2. Warning alert
+  const warningAlert: AlertRecord = {
+    id: 'sample-warning',
+    metric: 'memory_percent',
+    severity: 'warning',
+    message: 'Memory usage is high at 82.5% — consider checking for memory leaks',
+    value: 82.5,
+    threshold: 80,
+    firedAt: now,
+    resolvedAt: null,
+    emailSent: true,
+    acknowledged: false,
+  };
+  await transporter.sendMail({
+    from,
+    to,
+    subject: '[WARNING] Memory Usage alert — Eventify Server (Sample)',
+    html: buildAlertHtml(warningAlert),
+  });
+  sent.push('warning');
+
+  // 3. Info alert
+  const infoAlert: AlertRecord = {
+    id: 'sample-info',
+    metric: 'nginx_status',
+    severity: 'info',
+    message: 'Metric "nginx_status" could not be fetched — service may be temporarily unreachable',
+    value: 'N/A',
+    threshold: 'N/A',
+    firedAt: now,
+    resolvedAt: null,
+    emailSent: true,
+    acknowledged: false,
+  };
+  await transporter.sendMail({
+    from,
+    to,
+    subject: '[INFO] Nginx Status alert — Eventify Server (Sample)',
+    html: buildAlertHtml(infoAlert),
+  });
+  sent.push('info');
+
+  // 4. DDoS / High connections alert (critical)
+  const ddosAlert: AlertRecord = {
+    id: 'sample-ddos',
+    metric: 'connections_per_ip',
+    severity: 'critical',
+    message: 'Single IP (185.220.101.42) has 347 connections — possible DDoS attack (critically high)',
+    value: 347,
+    threshold: 100,
+    firedAt: now,
+    resolvedAt: null,
+    emailSent: true,
+    acknowledged: false,
+  };
+  await transporter.sendMail({
+    from,
+    to,
+    subject: '[CRITICAL] Connections per IP alert — Eventify Server (Sample)',
+    html: buildAlertHtml(ddosAlert),
+  });
+  sent.push('ddos');
+
+  // 5. High API request rate (warning)
+  const apiRateAlert: AlertRecord = {
+    id: 'sample-api-rate',
+    metric: 'request_rate',
+    severity: 'warning',
+    message: '2,847 HTTP requests/min — abnormally high API call volume (high)',
+    value: 2847,
+    threshold: 1000,
+    firedAt: now,
+    resolvedAt: null,
+    emailSent: true,
+    acknowledged: false,
+  };
+  await transporter.sendMail({
+    from,
+    to,
+    subject: '[WARNING] Request Rate alert — Eventify Server (Sample)',
+    html: buildAlertHtml(apiRateAlert),
+  });
+  sent.push('api-rate');
+
+  // 6. 5xx error spike (critical)
+  const errorAlert: AlertRecord = {
+    id: 'sample-5xx',
+    metric: 'error_rate_5xx',
+    severity: 'critical',
+    message: '73 server errors (5xx) in the last minute — service degradation (critically high)',
+    value: 73,
+    threshold: 50,
+    firedAt: now,
+    resolvedAt: null,
+    emailSent: true,
+    acknowledged: false,
+  };
+  await transporter.sendMail({
+    from,
+    to,
+    subject: '[CRITICAL] 5xx Error Rate alert — Eventify Server (Sample)',
+    html: buildAlertHtml(errorAlert),
+  });
+  sent.push('5xx-errors');
+
+  // 7. Recovery email
+  const recoveredAlert: AlertRecord = {
+    id: 'sample-recovery',
+    metric: 'connections_total',
+    severity: 'warning',
+    message: 'Total connections were high at 1,247 — traffic has normalized',
+    value: 1247,
+    threshold: 500,
+    firedAt: new Date(Date.now() - 45 * 60_000).toISOString(), // 45 min ago
+    resolvedAt: now,
+    emailSent: true,
+    acknowledged: false,
+  };
+  await transporter.sendMail({
+    from,
+    to,
+    subject: '[RESOLVED] Total Connections — Eventify Server (Sample)',
+    html: buildRecoveryHtml(recoveredAlert),
+  });
+  sent.push('recovery');
+
+  return { sent };
+}
diff --git a/server/src/services/scheduler.ts b/server/src/services/scheduler.ts
new file mode 100644
index 0000000..6408702
--- /dev/null
+++ b/server/src/services/scheduler.ts
@@ -0,0 +1,66 @@
+import cron from 'node-cron';
+import { getSystemInfo } from './system.js';
+import { getMemoryInfo } from './memory.js';
+import { getDiskInfo } from './disk.js';
+import { getDockerInfo } from './docker.js';
+import { getNginxStatus } from './nginx.js';
+import { getTrafficInfo } from './traffic.js';
+import { evaluateMetrics } from './alertEngine.js';
+import type { OverviewResponse } from '../types/index.js';
+
+let task: cron.ScheduledTask | null = null;
+
+async function runHealthCheck(): Promise<void> {
+  const errors: Record<string, string> = {};
+
+  const safe = async <T>(name: string, fn: () => Promise<T>): Promise<T | null> => {
+    try {
+      return await fn();
+    } catch (err) {
+      errors[name] = (err as Error).message ?? 'Unknown error';
+      return null;
+    }
+  };
+
+  const system = await safe('system', getSystemInfo);
+  const memory = await safe('memory', getMemoryInfo);
+  const disk   = await safe('disk', getDiskInfo);
+  const docker = await safe('docker', getDockerInfo);
+  const nginx   = await safe('nginx', getNginxStatus);
+  const traffic = await safe('traffic', getTrafficInfo);
+
+  const overview: OverviewResponse = {
+    system,
+    memory,
+    disk,
+    docker,
+    nginx,
+    traffic,
+    errors,
+    timestamp: new Date().toISOString(),
+  };
+
+  try {
+    await evaluateMetrics(overview);
+  } catch (err) {
+    console.error('[Scheduler] Alert evaluation error:', (err as Error).message);
+  }
+}
+
+export function startScheduler(): void {
+  if (task) return;
+  console.log('[Scheduler] Starting health check scheduler (every 1 minute)');
+  task = cron.schedule('*/1 * * * *', () => {
+    runHealthCheck().catch(err =>
+      console.error('[Scheduler] Health check failed:', (err as Error).message)
+    );
+  });
+}
+
+export function stopScheduler(): void {
+  if (task) {
+    task.stop();
+    task = null;
+    console.log('[Scheduler] Stopped');
+  }
+}
diff --git a/server/src/services/store.ts b/server/src/services/store.ts
new file mode 100644
index 0000000..8d88d24
--- /dev/null
+++ b/server/src/services/store.ts
@@ -0,0 +1,143 @@
+import { readFileSync, writeFileSync, renameSync, mkdirSync, existsSync } from 'fs';
+import { resolve } from 'path';
+import { config } from '../config.js';
+import type { AlertRecord, ThresholdsConfig, NotificationPreferences } from '../types/index.js';
+
+const MAX_ALERTS = 500;
+
+function dataPath(filename: string): string {
+  return resolve(config.dataDir, filename);
+}
+
+function ensureDir(): void {
+  if (!existsSync(config.dataDir)) {
+    mkdirSync(config.dataDir, { recursive: true });
+  }
+}
+
+function readJson<T>(filename: string, fallback: T): T {
+  ensureDir();
+  const path = dataPath(filename);
+  if (!existsSync(path)) return fallback;
+  try {
+    return JSON.parse(readFileSync(path, 'utf8')) as T;
+  } catch {
+    return fallback;
+  }
+}
+
+function writeJson<T>(filename: string, data: T): void {
+  ensureDir();
+  const path = dataPath(filename);
+  const tmp = path + '.tmp';
+  writeFileSync(tmp, JSON.stringify(data, null, 2), 'utf8');
+  renameSync(tmp, path);
+}
+
+// ── Thresholds ──
+
+const defaultThresholds: ThresholdsConfig = {
+  thresholds: [
+    { metric: 'cpu_percent',       warning: 80, critical: 95, enabled: true },
+    { metric: 'load_avg_1m',       warning: 4,  critical: 8,  enabled: true },
+    { metric: 'memory_percent',    warning: 80, critical: 95, enabled: true },
+    { metric: 'disk_percent',      warning: 80, critical: 95, enabled: true },
+    { metric: 'nginx_status',      warning: 0,  critical: 0,  enabled: true },
+    { metric: 'container_stopped', warning: 0,  critical: 0,  enabled: true },
+    { metric: 'connections_total', warning: 500, critical: 1000, enabled: true },
+    { metric: 'connections_per_ip', warning: 50, critical: 100, enabled: true },
+    { metric: 'request_rate',      warning: 1000, critical: 3000, enabled: true },
+    { metric: 'error_rate_5xx',    warning: 10, critical: 50, enabled: true },
+  ],
+  updatedAt: new Date().toISOString(),
+};
+
+export function getThresholds(): ThresholdsConfig {
+  const saved = readJson<ThresholdsConfig>('thresholds.json', defaultThresholds);
+  // Merge any new default metrics that don't exist in the saved file
+  const savedMetrics = new Set(saved.thresholds.map(t => t.metric));
+  const missing = defaultThresholds.thresholds.filter(t => !savedMetrics.has(t.metric));
+  if (missing.length > 0) {
+    saved.thresholds.push(...missing);
+    writeJson('thresholds.json', saved);
+  }
+  return saved;
+}
+
+export function saveThresholds(data: ThresholdsConfig): void {
+  writeJson('thresholds.json', { ...data, updatedAt: new Date().toISOString() });
+}
+
+// ── Alerts ──
+
+export function getAlerts(): AlertRecord[] {
+  return readJson<AlertRecord[]>('alerts.json', []);
+}
+
+export function saveAlerts(alerts: AlertRecord[]): void {
+  // Cap at MAX_ALERTS (FIFO — drop oldest resolved first, then oldest overall)
+  let trimmed = alerts;
+  if (trimmed.length > MAX_ALERTS) {
+    const resolved = trimmed.filter(a => a.resolvedAt !== null);
+    const active   = trimmed.filter(a => a.resolvedAt === null);
+    const combined = [...active, ...resolved].slice(0, MAX_ALERTS);
+    trimmed = combined;
+  }
+  writeJson('alerts.json', trimmed);
+}
+
+export function addAlert(alert: AlertRecord): void {
+  const alerts = getAlerts();
+  alerts.unshift(alert);
+  saveAlerts(alerts);
+}
+
+export function updateAlert(id: string, patch: Partial<AlertRecord>): AlertRecord | null {
+  const alerts = getAlerts();
+  const idx = alerts.findIndex(a => a.id === id);
+  if (idx === -1) return null;
+  alerts[idx] = { ...alerts[idx], ...patch };
+  saveAlerts(alerts);
+  return alerts[idx];
+}
+
+export function deleteAlert(id: string): boolean {
+  const alerts = getAlerts();
+  const filtered = alerts.filter(a => a.id !== id);
+  if (filtered.length === alerts.length) return false;
+  saveAlerts(filtered);
+  return true;
+}
+
+export function clearResolvedAlerts(): number {
+  const alerts = getAlerts();
+  const active = alerts.filter(a => a.resolvedAt === null);
+  const count = alerts.length - active.length;
+  saveAlerts(active);
+  return count;
+}
+
+export function getActiveAlerts(metric?: string): AlertRecord[] {
+  const alerts = getAlerts();
+  return alerts.filter(a => a.resolvedAt === null && (!metric || a.metric === metric));
+}
+
+// ── Preferences ──
+
+const defaultPreferences: NotificationPreferences = {
+  recipients: [
+    { email: 'nafih@bshtechnologies.in', name: 'Nafih', enabled: true },
+    { email: 'vivek@bshtechnologies.in', name: 'Vivek', enabled: true },
+  ],
+  cooldownMinutes: 15,
+  enabledSeverities: ['critical', 'warning', 'info'],
+  updatedAt: new Date().toISOString(),
+};
+
+export function getPreferences(): NotificationPreferences {
+  return readJson<NotificationPreferences>('preferences.json', defaultPreferences);
+}
+
+export function savePreferences(data: NotificationPreferences): void {
+  writeJson('preferences.json', { ...data, updatedAt: new Date().toISOString() });
+}
diff --git a/server/src/services/traffic.ts b/server/src/services/traffic.ts
new file mode 100644
index 0000000..13b4a23
--- /dev/null
+++ b/server/src/services/traffic.ts
@@ -0,0 +1,36 @@
+import { sshManager } from '../ssh/client.js';
+import type { TrafficInfo } from '../types/index.js';
+
+export async function getTrafficInfo(): Promise<TrafficInfo> {
+  // Run all traffic checks in a single SSH command for efficiency
+  const script = [
+    // 1. Total established TCP connections to ports 80/443
+    `echo "CONN_TOTAL=$(ss -t state established '( dport = :80 or dport = :443 or sport = :80 or sport = :443 )' 2>/dev/null | tail -n +2 | wc -l)"`,
+
+    // 2. Top IP by connection count + its count
+    `TOP=$(ss -t state established '( dport = :80 or dport = :443 or sport = :80 or sport = :443 )' 2>/dev/null | tail -n +2 | awk '{print $5}' | rev | cut -d: -f2- | rev | sort | uniq -c | sort -rn | head -1); echo "TOP_IP_COUNT=$(echo "$TOP" | awk '{print $1}')"; echo "TOP_IP=$(echo "$TOP" | awk '{print $2}')"`,
+
+    // 3. Nginx request rate (requests in last 60 seconds from access log)
+    `if [ -f /var/log/nginx/access.log ]; then CUTOFF=$(date -d '1 minute ago' '+%d/%b/%Y:%H:%M' 2>/dev/null || date -v-1M '+%d/%b/%Y:%H:%M' 2>/dev/null); REQ=$(awk -v cutoff="$CUTOFF" '$4 >= "["cutoff { count++ } END { print count+0 }' /var/log/nginx/access.log 2>/dev/null); echo "REQ_RATE=$REQ"; else echo "REQ_RATE=0"; fi`,
+
+    // 4. 5xx error rate (5xx responses in last 60 seconds)
+    `if [ -f /var/log/nginx/access.log ]; then CUTOFF=$(date -d '1 minute ago' '+%d/%b/%Y:%H:%M' 2>/dev/null || date -v-1M '+%d/%b/%Y:%H:%M' 2>/dev/null); ERR=$(awk -v cutoff="$CUTOFF" '$4 >= "["cutoff && $9 ~ /^5[0-9][0-9]$/ { count++ } END { print count+0 }' /var/log/nginx/access.log 2>/dev/null); echo "ERR_5XX=$ERR"; else echo "ERR_5XX=0"; fi`,
+  ].join(' && ');
+
+  const output = await sshManager.execCommand(script);
+
+  // Parse key=value pairs from output
+  const vars = new Map<string, string>();
+  for (const line of output.split('\n')) {
+    const match = line.match(/^(\w+)=(.*)$/);
+    if (match) vars.set(match[1], match[2].trim());
+  }
+
+  return {
+    totalConnections: parseInt(vars.get('CONN_TOTAL') ?? '0', 10) || 0,
+    topIpConnections: parseInt(vars.get('TOP_IP_COUNT') ?? '0', 10) || 0,
+    topIp: vars.get('TOP_IP') ?? 'none',
+    requestsPerMinute: parseInt(vars.get('REQ_RATE') ?? '0', 10) || 0,
+    errors5xxPerMinute: parseInt(vars.get('ERR_5XX') ?? '0', 10) || 0,
+  };
+}
diff --git a/server/src/types/index.ts b/server/src/types/index.ts
index 3416a7f..0834813 100644
--- a/server/src/types/index.ts
+++ b/server/src/types/index.ts
@@ -1,4 +1,5 @@
 // ─── Server Health Monitoring API Types ───
+export * from './notifications.js';
 
 export interface SystemInfo {
   hostname: string;
@@ -45,28 +46,12 @@ export interface NginxStatus {
   checkedAt: string;
 }
 
-// ─── User & Notification Types ───
-
-export type UserRole = 'developer' | 'server-admin';
-
-export interface MonitorUser {
-  id: string;
-  email: string;
-  name: string;
-  role: UserRole;
-  notifyOnError: boolean;
-  createdAt: string;
-}
-
-export interface Notification {
-  id: string;
-  type: 'error' | 'warning' | 'info' | 'recovery';
-  title: string;
-  message: string;
-  source: string;
-  timestamp: string;
-  read: boolean;
-  emailSent: boolean;
+export interface TrafficInfo {
+  totalConnections: number;
+  topIpConnections: number;
+  topIp: string;
+  requestsPerMinute: number;
+  errors5xxPerMinute: number;
 }
 
 export interface OverviewResponse {
@@ -75,6 +60,7 @@ export interface OverviewResponse {
   disk: DiskInfo | null;
   docker: DockerContainer[] | null;
   nginx: NginxStatus | null;
+  traffic: TrafficInfo | null;
   errors: Record<string, string>;
   timestamp: string;
 }
diff --git a/server/src/types/notifications.ts b/server/src/types/notifications.ts
new file mode 100644
index 0000000..9af5f21
--- /dev/null
+++ b/server/src/types/notifications.ts
@@ -0,0 +1,60 @@
+// ─── Notification & Alerting Types ───
+
+export type AlertSeverity = 'critical' | 'warning' | 'info';
+
+export type MetricKey =
+  | 'cpu_percent'
+  | 'load_avg_1m'
+  | 'memory_percent'
+  | 'disk_percent'
+  | 'nginx_status'
+  | 'container_stopped'
+  | 'connections_total'
+  | 'connections_per_ip'
+  | 'request_rate'
+  | 'error_rate_5xx';
+
+export interface ThresholdConfig {
+  metric: MetricKey;
+  warning: number;
+  critical: number;
+  enabled: boolean;
+}
+
+export interface ThresholdsConfig {
+  thresholds: ThresholdConfig[];
+  updatedAt: string;
+}
+
+export interface AlertRecord {
+  id: string;
+  metric: MetricKey;
+  severity: AlertSeverity;
+  message: string;
+  value: number | string;
+  threshold: number | string;
+  firedAt: string;
+  resolvedAt: string | null;
+  emailSent: boolean;
+  acknowledged: boolean;
+}
+
+export interface NotificationPreferences {
+  recipients: EmailRecipient[];
+  cooldownMinutes: number;
+  enabledSeverities: AlertSeverity[];
+  updatedAt: string;
+}
+
+export interface EmailRecipient {
+  email: string;
+  name: string;
+  enabled: boolean;
+}
+
+export interface NotificationSummary {
+  activeWarnings: number;
+  activeCriticals: number;
+  unacknowledged: number;
+  total: number;
+}