diff --git a/src/design-system/layout/AppShell/AppShell.module.css b/src/design-system/layout/AppShell/AppShell.module.css
new file mode 100644
index 0000000..866a9cd
--- /dev/null
+++ b/src/design-system/layout/AppShell/AppShell.module.css
@@ -0,0 +1,13 @@
+.app {
+  display: flex;
+  height: 100vh;
+  overflow: hidden;
+}
+
+.main {
+  flex: 1;
+  display: flex;
+  flex-direction: column;
+  overflow: hidden;
+  min-width: 0;
+}
diff --git a/src/design-system/layout/AppShell/AppShell.tsx b/src/design-system/layout/AppShell/AppShell.tsx
new file mode 100644
index 0000000..8083e52
--- /dev/null
+++ b/src/design-system/layout/AppShell/AppShell.tsx
@@ -0,0 +1,20 @@
+import styles from './AppShell.module.css'
+import type { ReactNode } from 'react'
+
+interface AppShellProps {
+  sidebar: ReactNode
+  children: ReactNode
+  detail?: ReactNode
+}
+
+export function AppShell({ sidebar, children, detail }: AppShellProps) {
+  return (
+    <div className={styles.app}>
+      {sidebar}
+      <div className={styles.main}>
+        {children}
+      </div>
+      {detail}
+    </div>
+  )
+}
diff --git a/src/design-system/layout/Sidebar/Sidebar.module.css b/src/design-system/layout/Sidebar/Sidebar.module.css
new file mode 100644
index 0000000..045fae7
--- /dev/null
+++ b/src/design-system/layout/Sidebar/Sidebar.module.css
@@ -0,0 +1,319 @@
+.sidebar {
+  width: 220px;
+  flex-shrink: 0;
+  background: var(--sidebar-bg);
+  display: flex;
+  flex-direction: column;
+  overflow: hidden;
+}
+
+/* Logo */
+.logo {
+  padding: 16px 18px;
+  display: flex;
+  align-items: center;
+  gap: 10px;
+  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
+  flex-shrink: 0;
+}
+
+.brand {
+  font-family: var(--font-mono);
+  font-weight: 600;
+  font-size: 15px;
+  color: var(--amber-light);
+  letter-spacing: -0.3px;
+}
+
+.version {
+  font-family: var(--font-mono);
+  font-size: 10px;
+  color: var(--sidebar-muted);
+  margin-left: 4px;
+}
+
+/* Search */
+.searchWrap {
+  padding: 10px 12px;
+  flex-shrink: 0;
+}
+
+.searchInner {
+  position: relative;
+}
+
+.searchInput {
+  width: 100%;
+  background: rgba(255, 255, 255, 0.06);
+  border: 1px solid rgba(255, 255, 255, 0.08);
+  border-radius: var(--radius-sm);
+  padding: 6px 10px 6px 28px;
+  color: var(--sidebar-text);
+  font-family: var(--font-body);
+  font-size: 12px;
+  outline: none;
+  transition: border-color 0.15s;
+}
+
+.searchInput::placeholder {
+  color: var(--sidebar-muted);
+}
+
+.searchInput:focus {
+  border-color: rgba(198, 130, 14, 0.4);
+}
+
+.searchIcon {
+  position: absolute;
+  left: 9px;
+  top: 50%;
+  transform: translateY(-50%);
+  color: var(--sidebar-muted);
+  display: flex;
+  align-items: center;
+}
+
+/* Scrollable nav area */
+.navArea {
+  flex: 1;
+  overflow-y: auto;
+  min-height: 0;
+}
+
+/* Section headers */
+.section {
+  padding: 14px 12px 5px;
+  font-size: 10px;
+  font-weight: 600;
+  text-transform: uppercase;
+  letter-spacing: 1.2px;
+  color: var(--sidebar-muted);
+}
+
+/* Items container */
+.items {
+  padding: 0 6px;
+}
+
+/* Nav item */
+.item {
+  display: flex;
+  align-items: center;
+  gap: 10px;
+  padding: 7px 12px;
+  border-radius: var(--radius-sm);
+  color: var(--sidebar-text);
+  font-size: 13px;
+  cursor: pointer;
+  transition: all 0.12s;
+  border-left: 3px solid transparent;
+  margin-bottom: 1px;
+  user-select: none;
+}
+
+.item:hover {
+  background: var(--sidebar-hover);
+  color: #e8dfd4;
+}
+
+.item.active {
+  background: var(--sidebar-active);
+  color: var(--amber-light);
+  border-left-color: var(--amber);
+}
+
+.item.active .itemCount {
+  background: rgba(198, 130, 14, 0.2);
+  color: var(--amber-light);
+}
+
+/* Indented route items */
+.indented {
+  padding-left: 22px;
+}
+
+.routeArrow {
+  color: var(--sidebar-muted);
+  font-size: 10px;
+}
+
+/* Item sub-elements */
+.itemInfo {
+  flex: 1;
+  min-width: 0;
+}
+
+.itemName {
+  font-weight: 500;
+  white-space: nowrap;
+  overflow: hidden;
+  text-overflow: ellipsis;
+}
+
+.itemMeta {
+  font-size: 11px;
+  color: var(--sidebar-muted);
+  font-family: var(--font-mono);
+}
+
+.itemCount {
+  font-family: var(--font-mono);
+  font-size: 11px;
+  color: var(--sidebar-muted);
+  background: rgba(255, 255, 255, 0.06);
+  padding: 1px 6px;
+  border-radius: 10px;
+  flex-shrink: 0;
+}
+
+/* Health dots */
+.healthDot {
+  width: 7px;
+  height: 7px;
+  border-radius: 50%;
+  flex-shrink: 0;
+}
+
+.healthLive {
+  background: #5db866;
+  box-shadow: 0 0 6px rgba(93, 184, 102, 0.4);
+}
+
+.healthStale {
+  background: var(--warning);
+}
+
+.healthDead {
+  background: var(--sidebar-muted);
+}
+
+/* Divider */
+.divider {
+  height: 1px;
+  background: rgba(255, 255, 255, 0.06);
+  margin: 6px 12px;
+}
+
+/* Agents header */
+.agentsHeader {
+  padding: 14px 12px 6px;
+  font-size: 10px;
+  font-weight: 600;
+  text-transform: uppercase;
+  letter-spacing: 1.2px;
+  color: var(--sidebar-muted);
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  flex-shrink: 0;
+}
+
+.agentBadge {
+  font-family: var(--font-mono);
+  font-size: 10px;
+  padding: 1px 6px;
+  border-radius: 10px;
+  background: rgba(93, 184, 102, 0.15);
+  color: #5db866;
+}
+
+/* Agents list */
+.agentsList {
+  padding: 0 0 6px;
+  overflow-y: auto;
+  max-height: 180px;
+  flex-shrink: 0;
+}
+
+.agentItem {
+  display: flex;
+  align-items: center;
+  gap: 8px;
+  padding: 6px 12px;
+  margin: 0 6px 2px;
+  border-radius: var(--radius-sm);
+  font-size: 11px;
+  color: var(--sidebar-text);
+  transition: background 0.1s;
+}
+
+.agentItem:hover {
+  background: var(--sidebar-hover);
+}
+
+.agentDot {
+  width: 6px;
+  height: 6px;
+  border-radius: 50%;
+  flex-shrink: 0;
+}
+
+.agentInfo {
+  flex: 1;
+  min-width: 0;
+}
+
+.agentName {
+  font-family: var(--font-mono);
+  font-size: 11px;
+  font-weight: 500;
+  white-space: nowrap;
+  overflow: hidden;
+  text-overflow: ellipsis;
+}
+
+.agentDetail {
+  font-size: 10px;
+  color: var(--sidebar-muted);
+}
+
+.agentStats {
+  text-align: right;
+  font-family: var(--font-mono);
+  font-size: 10px;
+  color: var(--sidebar-muted);
+}
+
+.agentTps {
+  color: var(--sidebar-text);
+}
+
+.agentLastSeen {
+  color: var(--sidebar-muted);
+}
+
+.agentError {
+  color: var(--error);
+}
+
+/* Bottom links */
+.bottom {
+  border-top: 1px solid rgba(255, 255, 255, 0.06);
+  padding: 6px;
+  flex-shrink: 0;
+}
+
+.bottomItem {
+  display: flex;
+  align-items: center;
+  gap: 10px;
+  padding: 7px 12px;
+  border-radius: var(--radius-sm);
+  color: var(--sidebar-muted);
+  font-size: 12px;
+  cursor: pointer;
+  transition: all 0.12s;
+  border-left: 3px solid transparent;
+  margin-bottom: 1px;
+}
+
+.bottomItem:hover {
+  background: var(--sidebar-hover);
+  color: var(--sidebar-text);
+}
+
+.bottomIcon {
+  font-size: 13px;
+  width: 18px;
+  text-align: center;
+}
diff --git a/src/design-system/layout/Sidebar/Sidebar.tsx b/src/design-system/layout/Sidebar/Sidebar.tsx
new file mode 100644
index 0000000..d974280
--- /dev/null
+++ b/src/design-system/layout/Sidebar/Sidebar.tsx
@@ -0,0 +1,241 @@
+import { useState } from 'react'
+import styles from './Sidebar.module.css'
+
+export interface App {
+  id: string
+  name: string
+  agentCount: number
+  health: 'live' | 'stale' | 'dead'
+  execCount: number
+}
+
+export interface Route {
+  id: string
+  name: string
+  execCount: number
+}
+
+export interface Agent {
+  id: string
+  name: string
+  service: string
+  version: string
+  tps: string
+  lastSeen: string
+  status: 'live' | 'stale' | 'dead'
+  errorRate?: string
+}
+
+interface SidebarProps {
+  apps: App[]
+  routes: Route[]
+  agents: Agent[]
+  activeItem?: string
+  onItemClick?: (id: string) => void
+}
+
+function HealthDot({ status }: { status: 'live' | 'stale' | 'dead' }) {
+  return (
+    <span
+      className={[
+        styles.healthDot,
+        status === 'live' ? styles.healthLive : '',
+        status === 'stale' ? styles.healthStale : '',
+        status === 'dead' ? styles.healthDead : '',
+      ]
+        .filter(Boolean)
+        .join(' ')}
+    />
+  )
+}
+
+// Camel SVG silhouette
+function CamelIcon() {
+  return (
+    <svg
+      width="28"
+      height="24"
+      viewBox="0 0 28 24"
+      fill="none"
+      xmlns="http://www.w3.org/2000/svg"
+      aria-hidden="true"
+    >
+      {/* Simple camel silhouette */}
+      <path
+        d="M4 20 L4 16 L6 14 L6 12 C6 10 7 9 9 9 L10 8 C10 6 11 5 12 5 C12 3 13 2 14 2 C15 2 15.5 3 15 5 C16 5 17 6 17 8 L18 9 C20 9 21 10 21 12 L21 14 L22 14 L22 12 C22 10 23 9 24 9 L24 20"
+        fill="var(--amber-light)"
+        stroke="var(--amber)"
+        strokeWidth="0.5"
+      />
+      <path
+        d="M4 20 L24 20"
+        stroke="var(--amber)"
+        strokeWidth="1"
+        strokeLinecap="round"
+      />
+    </svg>
+  )
+}
+
+export function Sidebar({
+  apps,
+  routes,
+  agents,
+  activeItem,
+  onItemClick,
+}: SidebarProps) {
+  const [search, setSearch] = useState('')
+
+  const liveCount = agents.filter((a) => a.status === 'live').length
+  const agentBadge = `${liveCount}/${agents.length} live`
+
+  const filteredApps = search
+    ? apps.filter((a) => a.name.toLowerCase().includes(search.toLowerCase()))
+    : apps
+
+  return (
+    <aside className={styles.sidebar}>
+      {/* Logo */}
+      <div className={styles.logo}>
+        <CamelIcon />
+        <div>
+          <span className={styles.brand}>cameleer</span>
+          <span className={styles.version}>v3.2.1</span>
+        </div>
+      </div>
+
+      {/* Search */}
+      <div className={styles.searchWrap}>
+        <div className={styles.searchInner}>
+          <span className={styles.searchIcon} aria-hidden="true">
+            <svg width="12" height="12" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round">
+              <circle cx="11" cy="11" r="8" />
+              <line x1="21" y1="21" x2="16.65" y2="16.65" />
+            </svg>
+          </span>
+          <input
+            className={styles.searchInput}
+            type="text"
+            placeholder="Filter apps..."
+            value={search}
+            onChange={(e) => setSearch(e.target.value)}
+          />
+        </div>
+      </div>
+
+      {/* Scrollable nav area */}
+      <div className={styles.navArea}>
+        {/* Applications section */}
+        <div className={styles.section}>Applications</div>
+        <div className={styles.items}>
+          {filteredApps.map((app) => (
+            <div
+              key={app.id}
+              className={[
+                styles.item,
+                activeItem === app.id ? styles.active : '',
+              ]
+                .filter(Boolean)
+                .join(' ')}
+              onClick={() => onItemClick?.(app.id)}
+              role="button"
+              tabIndex={0}
+              onKeyDown={(e) => {
+                if (e.key === 'Enter' || e.key === ' ') onItemClick?.(app.id)
+              }}
+            >
+              <HealthDot status={app.health} />
+              <div className={styles.itemInfo}>
+                <div className={styles.itemName}>{app.name}</div>
+                <div className={styles.itemMeta}>{app.agentCount} agent{app.agentCount !== 1 ? 's' : ''}</div>
+              </div>
+              <span className={styles.itemCount}>{app.execCount.toLocaleString()}</span>
+            </div>
+          ))}
+        </div>
+
+        {/* Divider */}
+        <div className={styles.divider} />
+
+        {/* Routes section */}
+        <div className={styles.section}>Routes</div>
+        <div className={styles.items}>
+          {routes.map((route) => (
+            <div
+              key={route.id}
+              className={[
+                styles.item,
+                styles.indented,
+                activeItem === route.id ? styles.active : '',
+              ]
+                .filter(Boolean)
+                .join(' ')}
+              onClick={() => onItemClick?.(route.id)}
+              role="button"
+              tabIndex={0}
+              onKeyDown={(e) => {
+                if (e.key === 'Enter' || e.key === ' ') onItemClick?.(route.id)
+              }}
+            >
+              <span className={styles.routeArrow}>&#9656;</span>
+              <div className={styles.itemInfo}>
+                <div className={styles.itemName}>{route.name}</div>
+              </div>
+              <span className={styles.itemCount}>{route.execCount.toLocaleString()}</span>
+            </div>
+          ))}
+        </div>
+      </div>
+
+      {/* Agent health section */}
+      <div className={styles.agentsHeader}>
+        <span>Agents</span>
+        <span className={styles.agentBadge}>{agentBadge}</span>
+      </div>
+      <div className={styles.agentsList}>
+        {agents.map((agent) => (
+          <div key={agent.id} className={styles.agentItem}>
+            <span
+              className={[
+                styles.agentDot,
+                agent.status === 'live' ? styles.healthLive : '',
+                agent.status === 'stale' ? styles.healthStale : '',
+                agent.status === 'dead' ? styles.healthDead : '',
+              ]
+                .filter(Boolean)
+                .join(' ')}
+            />
+            <div className={styles.agentInfo}>
+              <div className={styles.agentName}>{agent.name}</div>
+              <div className={styles.agentDetail}>{agent.service} {agent.version}</div>
+            </div>
+            <div className={styles.agentStats}>
+              <div className={styles.agentTps}>{agent.tps}</div>
+              <div
+                className={agent.errorRate ? styles.agentError : styles.agentLastSeen}
+              >
+                {agent.errorRate ?? agent.lastSeen}
+              </div>
+            </div>
+          </div>
+        ))}
+      </div>
+
+      {/* Bottom links */}
+      <div className={styles.bottom}>
+        <div className={styles.bottomItem}>
+          <span className={styles.bottomIcon}>&#9881;</span>
+          <div className={styles.itemInfo}>
+            <div className={styles.itemName}>Admin</div>
+          </div>
+        </div>
+        <div className={styles.bottomItem}>
+          <span className={styles.bottomIcon}>&#9776;</span>
+          <div className={styles.itemInfo}>
+            <div className={styles.itemName}>API Docs</div>
+          </div>
+        </div>
+      </div>
+    </aside>
+  )
+}
diff --git a/src/design-system/layout/TopBar/TopBar.module.css b/src/design-system/layout/TopBar/TopBar.module.css
new file mode 100644
index 0000000..e66a8ea
--- /dev/null
+++ b/src/design-system/layout/TopBar/TopBar.module.css
@@ -0,0 +1,110 @@
+.topbar {
+  display: flex;
+  align-items: center;
+  gap: 12px;
+  padding: 0 24px;
+  height: 48px;
+  flex-shrink: 0;
+  background: var(--bg-surface);
+  border-bottom: 1px solid var(--border);
+}
+
+/* Breadcrumb area - left side */
+.breadcrumb {
+  flex-shrink: 0;
+}
+
+/* Center search trigger */
+.search {
+  display: flex;
+  align-items: center;
+  gap: 6px;
+  padding: 5px 12px;
+  border: 1px solid var(--border);
+  border-radius: var(--radius-sm);
+  background: var(--bg-raised);
+  color: var(--text-muted);
+  font-size: 12px;
+  font-family: var(--font-body);
+  cursor: pointer;
+  transition: border-color 0.15s;
+  min-width: 280px;
+  flex: 1;
+  max-width: 400px;
+  text-align: left;
+}
+
+.search:hover {
+  border-color: var(--text-faint);
+}
+
+.searchIcon {
+  display: flex;
+  align-items: center;
+  color: var(--text-faint);
+  flex-shrink: 0;
+}
+
+.searchPlaceholder {
+  flex: 1;
+  white-space: nowrap;
+  overflow: hidden;
+  text-overflow: ellipsis;
+}
+
+.kbd {
+  font-family: var(--font-mono);
+  font-size: 10px;
+  background: var(--bg-surface);
+  border: 1px solid var(--border);
+  padding: 0 4px;
+  border-radius: 3px;
+  color: var(--text-faint);
+  flex-shrink: 0;
+  line-height: 1.6;
+}
+
+/* Right section */
+.right {
+  margin-left: auto;
+  display: flex;
+  align-items: center;
+  gap: 12px;
+  flex-shrink: 0;
+}
+
+.env {
+  font-family: var(--font-mono);
+  font-size: 10px;
+  font-weight: 600;
+  padding: 3px 10px;
+  border-radius: 10px;
+  background: var(--success-bg);
+  color: var(--success);
+  border: 1px solid var(--success-border);
+  text-transform: uppercase;
+  letter-spacing: 0.5px;
+}
+
+.shift {
+  font-family: var(--font-mono);
+  font-size: 10px;
+  padding: 3px 10px;
+  border-radius: 10px;
+  background: var(--running-bg);
+  color: var(--running);
+  border: 1px solid var(--running-border);
+}
+
+.user {
+  display: flex;
+  align-items: center;
+  gap: 8px;
+  font-size: 12px;
+  color: var(--text-secondary);
+}
+
+.userName {
+  color: var(--text-secondary);
+  font-size: 12px;
+}
diff --git a/src/design-system/layout/TopBar/TopBar.tsx b/src/design-system/layout/TopBar/TopBar.tsx
new file mode 100644
index 0000000..abd165d
--- /dev/null
+++ b/src/design-system/layout/TopBar/TopBar.tsx
@@ -0,0 +1,66 @@
+import styles from './TopBar.module.css'
+import { Breadcrumb } from '../../composites/Breadcrumb/Breadcrumb'
+import { Avatar } from '../../primitives/Avatar/Avatar'
+
+interface BreadcrumbItem {
+  label: string
+  href?: string
+}
+
+interface TopBarProps {
+  breadcrumb: BreadcrumbItem[]
+  environment?: string
+  shift?: string
+  user?: { name: string }
+  onSearchClick?: () => void
+  className?: string
+}
+
+export function TopBar({
+  breadcrumb,
+  environment,
+  shift,
+  user,
+  onSearchClick,
+  className,
+}: TopBarProps) {
+  return (
+    <header className={`${styles.topbar} ${className ?? ''}`}>
+      {/* Left: Breadcrumb */}
+      <Breadcrumb items={breadcrumb} className={styles.breadcrumb} />
+
+      {/* Center: Search trigger */}
+      <button
+        className={styles.search}
+        onClick={onSearchClick}
+        type="button"
+        aria-label="Open search"
+      >
+        <span className={styles.searchIcon} aria-hidden="true">
+          <svg width="13" height="13" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round">
+            <circle cx="11" cy="11" r="8" />
+            <line x1="21" y1="21" x2="16.65" y2="16.65" />
+          </svg>
+        </span>
+        <span className={styles.searchPlaceholder}>Search by Order ID, route, error...</span>
+        <span className={styles.kbd}>Ctrl+K</span>
+      </button>
+
+      {/* Right: env badge, shift, user */}
+      <div className={styles.right}>
+        {environment && (
+          <span className={styles.env}>{environment}</span>
+        )}
+        {shift && (
+          <span className={styles.shift}>Shift: {shift}</span>
+        )}
+        {user && (
+          <div className={styles.user}>
+            <span className={styles.userName}>{user.name}</span>
+            <Avatar name={user.name} size="md" />
+          </div>
+        )}
+      </div>
+    </header>
+  )
+}
diff --git a/src/design-system/layout/index.ts b/src/design-system/layout/index.ts
new file mode 100644
index 0000000..b911ccd
--- /dev/null
+++ b/src/design-system/layout/index.ts
@@ -0,0 +1,4 @@
+export { AppShell } from './AppShell/AppShell'
+export { Sidebar } from './Sidebar/Sidebar'
+export type { App, Route, Agent } from './Sidebar/Sidebar'
+export { TopBar } from './TopBar/TopBar'