diff --git a/db.js b/db.js
index db795c3..f9ecd64 100644
--- a/db.js
+++ b/db.js
@@ -296,6 +296,100 @@ function setStructurePublic(structureId, isPublic) {
   );
 }
 
+// ---- kernel notifications -------------------------------------------------
+//
+// Subscriptions are owned by the platform, not by structure databases. Each row
+// is tied to exactly one structure and one logged-in Bliss user; send-time code
+// re-checks canAccessStructure before handing anything to a push service.
+
+function upsertNotificationSubscription({
+  structureId,
+  userId,
+  endpoint,
+  clientId,
+  subscription,
+  contentEncoding,
+}) {
+  return db
+    .prepare(
+      `INSERT INTO notification_subscriptions
+         (structure_id, user_id, endpoint, client_id, subscription, content_encoding, updated_at)
+       VALUES (?, ?, ?, ?, ?, ?, CURRENT_TIMESTAMP)
+       ON CONFLICT(structure_id, endpoint) DO UPDATE SET
+         user_id = excluded.user_id,
+         client_id = excluded.client_id,
+         subscription = excluded.subscription,
+         content_encoding = excluded.content_encoding,
+         updated_at = CURRENT_TIMESTAMP`,
+    )
+    .run(
+      structureId,
+      userId,
+      endpoint,
+      clientId == null ? null : String(clientId),
+      JSON.stringify(subscription),
+      contentEncoding === "aesgcm" ? "aesgcm" : "aes128gcm",
+    );
+}
+
+function deleteNotificationSubscription(structureId, endpoint) {
+  return db
+    .prepare(
+      `DELETE FROM notification_subscriptions
+       WHERE structure_id = ? AND endpoint = ?`,
+    )
+    .run(structureId, endpoint);
+}
+
+function getNotificationSubscriptions(structureId, userIds = null) {
+  if (userIds && userIds.length === 0) return [];
+  const rows = userIds
+    ? db
+        .prepare(
+          `SELECT *
+             FROM notification_subscriptions
+            WHERE structure_id = ?
+              AND user_id IN (${userIds.map(() => "?").join(",")})`,
+        )
+        .all(structureId, ...userIds)
+    : db
+        .prepare(
+          `SELECT *
+             FROM notification_subscriptions
+            WHERE structure_id = ?`,
+        )
+        .all(structureId);
+
+  return rows.map((row) => ({
+    ...row,
+    subscription: JSON.parse(row.subscription),
+  }));
+}
+
+function getSubscribedNotificationUserIds(structureId) {
+  return db
+    .prepare(
+      `SELECT DISTINCT user_id
+         FROM notification_subscriptions
+        WHERE structure_id = ?
+        ORDER BY user_id`,
+    )
+    .all(structureId)
+    .map((row) => row.user_id);
+}
+
+function getStructureMemberUserIds(structureId) {
+  return db
+    .prepare(
+      `SELECT user_id
+         FROM structure_members
+        WHERE structure_id = ?
+        ORDER BY user_id`,
+    )
+    .all(structureId)
+    .map((row) => row.user_id);
+}
+
 function createRoute(verb, path, structureId, handler) {
   path = encodeURI(path);
 
@@ -890,6 +984,11 @@ module.exports = {
   removeMember,
   setStructurePrivacy,
   setStructurePublic,
+  upsertNotificationSubscription,
+  deleteNotificationSubscription,
+  getNotificationSubscriptions,
+  getSubscribedNotificationUserIds,
+  getStructureMemberUserIds,
   createRoute,
   getRoutes,
   getRoute,
diff --git a/index.js b/index.js
index 3fa42ff..cb8ceea 100644
--- a/index.js
+++ b/index.js
@@ -210,6 +210,7 @@ function makeLibs(structureId, console, memberUserId) {
       return dbs[alias];
     },
     push: push,
+    notifications: makeNotifications(structureId, memberUserId),
     files: { saveFile: (...args) => saveFile(structureId, ...args) },
   };
 }
@@ -228,6 +229,126 @@ function currentUserFor(req) {
   }
 }
 
+function userIdFrom(value) {
+  if (value == null) return null;
+  if (typeof value === "object" && value.id != null) return Number(value.id);
+  const n = Number(value);
+  return Number.isInteger(n) ? n : null;
+}
+
+function normalizeNotificationUrl(structure, rawUrl) {
+  const route = makeRoute(structure);
+  const url = rawUrl == null || rawUrl === "" ? "/" : String(rawUrl);
+  if (!url.startsWith("/") || url.startsWith("//")) {
+    throw new Error("notification url must be a same-site path");
+  }
+  const prefix = structure.route_prefix || "";
+  const scoped = prefix && !url.startsWith(prefix) ? route(url) : url;
+  if (prefix && scoped !== prefix && !scoped.startsWith(prefix + "/")) {
+    throw new Error("notification url must stay inside this structure");
+  }
+  return scoped;
+}
+
+function normalizeNotificationRecipients(structureId, target) {
+  const explicit = target !== "viewers" && target !== "subscribers";
+  let ids;
+
+  if (target == null || target === "viewers" || target === "subscribers") {
+    ids = model.getSubscribedNotificationUserIds(structureId);
+  } else if (target === "members") {
+    ids = model.getStructureMemberUserIds(structureId);
+  } else if (Array.isArray(target)) {
+    ids = target.map(userIdFrom);
+  } else {
+    ids = [userIdFrom(target)];
+  }
+
+  if (ids.some((id) => !Number.isInteger(id))) {
+    throw new Error("notification recipient must be a Bliss user");
+  }
+
+  const unique = [...new Set(ids)];
+  const forbidden = unique.filter(
+    (id) => !model.canAccessStructure(id, structureId),
+  );
+  if (forbidden.length && explicit) {
+    throw new Error("notification recipient cannot access this structure");
+  }
+  return unique.filter((id) => !forbidden.includes(id));
+}
+
+function normalizeNotificationExclusions(options = {}) {
+  const ids = [];
+  const collect = (value) => {
+    if (Array.isArray(value)) return value.forEach(collect);
+    const id = userIdFrom(value);
+    if (id != null) ids.push(id);
+  };
+  collect(options.except);
+  collect(options.exceptUser);
+  collect(options.exceptUserId);
+  return {
+    userIds: new Set(ids),
+    clientId:
+      options.exceptClientId == null ? null : String(options.exceptClientId),
+  };
+}
+
+function makeNotifications(structureId, actorUserId) {
+  const structure = model.getStructure(structureId);
+  return {
+    async send(options = {}) {
+      const target = options.to ?? options.users ?? options.user ?? "viewers";
+      const recipientIds = normalizeNotificationRecipients(structureId, target);
+      const except = normalizeNotificationExclusions(options);
+      const eligibleIds = recipientIds.filter((id) => !except.userIds.has(id));
+      const url = normalizeNotificationUrl(structure, options.url || "/");
+      const rows = model.getNotificationSubscriptions(structureId, eligibleIds);
+      const payload = JSON.stringify({
+        structureId: String(structureId),
+        title: String(options.title || structure.name || "Bliss"),
+        body: String(options.body || ""),
+        url,
+      });
+      let sent = 0;
+      let skipped = 0;
+
+      await Promise.all(
+        rows.map(async (row) => {
+          if (except.clientId && row.client_id === except.clientId) {
+            skipped += 1;
+            return;
+          }
+          if (!model.canAccessStructure(row.user_id, structureId)) {
+            skipped += 1;
+            return;
+          }
+          try {
+            await push.sendNotification(row.subscription, payload, {
+              contentEncoding: row.content_encoding || undefined,
+            });
+            sent += 1;
+          } catch (err) {
+            if (err && (err.statusCode === 404 || err.statusCode === 410)) {
+              model.deleteNotificationSubscription(structureId, row.endpoint);
+            } else {
+              throw err;
+            }
+          }
+        }),
+      );
+
+      return {
+        sent,
+        skipped,
+        structureId,
+        actorUserId: actorUserId ?? null,
+      };
+    },
+  };
+}
+
 function bootstrapContext(structureId, routeId, initContext, memberUserId) {
   const structure = model.getStructure(structureId);
   const console = makeConsole(structureId, routeId);
@@ -363,6 +484,10 @@ wsRouter.ws("*", (ws, req) => {
       }),
     );
   };
+  req.user = req.currentUser;
+  req.notifications = makeNotifications(route.structure_id, req.session.userId);
+  ws.user = req.currentUser;
+  ws.notifications = req.notifications;
 
   try {
     return found.handler(ws, req);
@@ -450,6 +575,85 @@ app.all("/logout", async (req, res) => {
   });
 });
 
+app.get("/_bliss/notifications/key", (req, res) => {
+  if (!vapidPublicKey) return res.status(503).json({ error: "not configured" });
+  res.json({ publicKey: vapidPublicKey });
+});
+
+app.post("/_bliss/notifications/subscribe", (req, res) => {
+  const structureId = Number(req.body?.structure_id);
+  const userId = req.session && req.session.userId;
+  const subscription = req.body?.subscription;
+  if (!userId)
+    return res.status(401).send("log in before enabling notifications");
+  if (!Number.isInteger(structureId) || !model.getStructure(structureId)) {
+    return res.status(400).send("unknown structure");
+  }
+  if (!model.canAccessStructure(userId, structureId)) {
+    return res.status(403).send("you cannot access this structure");
+  }
+  if (!subscription || !subscription.endpoint) {
+    return res.status(400).send("missing push subscription");
+  }
+
+  model.upsertNotificationSubscription({
+    structureId,
+    userId,
+    endpoint: subscription.endpoint,
+    clientId: req.body?.client_id,
+    subscription,
+    contentEncoding: req.body?.content_encoding,
+  });
+  res.status(201).json({ ok: true });
+});
+
+app.get("/_bliss/notification-sw.js", (req, res) => {
+  res.type("application/javascript").set("Cache-Control", "no-cache").send(`
+const openStructures = new Set();
+
+self.addEventListener("install", (event) => event.waitUntil(self.skipWaiting()));
+self.addEventListener("activate", (event) => event.waitUntil(self.clients.claim()));
+
+self.addEventListener("message", (event) => {
+  const data = event.data || {};
+  if (data.type !== "bliss:visibility" || !data.structureId) return;
+  const id = String(data.structureId);
+  if (data.state === "open") {
+    openStructures.add(id);
+    self.registration.getNotifications({ tag: "bliss:" + id }).then((items) => items.forEach((n) => n.close()));
+  } else {
+    openStructures.delete(id);
+  }
+});
+
+self.addEventListener("push", (event) => {
+  let data = {};
+  try { data = event.data ? event.data.json() : {}; } catch (_) {}
+  const structureId = String(data.structureId || "");
+  if (structureId && openStructures.has(structureId)) return;
+  event.waitUntil(self.registration.showNotification(data.title || "Bliss", {
+    body: data.body || "",
+    tag: structureId ? "bliss:" + structureId : "bliss",
+    data: { url: data.url || "/" },
+  }));
+});
+
+self.addEventListener("notificationclick", (event) => {
+  event.notification.close();
+  const target = event.notification.data && event.notification.data.url || "/";
+  event.waitUntil(clients.matchAll({ type: "window", includeUncontrolled: true }).then((items) => {
+    for (const client of items) {
+      try {
+        const url = new URL(client.url);
+        if (url.pathname === target && "focus" in client) return client.focus();
+      } catch (_) {}
+    }
+    if (clients.openWindow) return clients.openWindow(target);
+  }));
+});
+`);
+});
+
 // _     _  _______  ______    ___   _  _______  __   __  _______  _______
 // | | _ | ||       ||    _ |  |   | | ||       ||  | |  ||       ||       |
 // | || || ||   _   ||   | ||  |   |_| ||  _____||  |_|  ||   _   ||    _  |
@@ -467,6 +671,7 @@ function headChrome(headInjection) {
         <script src="/js/htmx.js"></script>
         <script src="/js/ace/ace.js"></script>
         <script src="https://unpkg.com/htmx.org@1.9.12/dist/ext/ws.js"></script>
+        <script src="/js/bliss.js"></script>
         <script src="/js/bliss_inspector.js"></script>
         <script>
           tailwind.config = {
@@ -1119,6 +1324,11 @@ app.all("*", async (req, res) => {
       // Deliberately NOT the raw session/user object — just {id, username} —
       // so structures can greet whoever is logged in without exposing internals.
       req.currentUser = currentUserFor(req);
+      req.user = req.currentUser;
+      req.notifications = makeNotifications(
+        route.structure_id,
+        req.session.userId,
+      );
 
       const structure = model.getStructure(route.structure_id);
 
@@ -1128,7 +1338,7 @@ app.all("*", async (req, res) => {
         let context = bootstrapContext(
           route.structure_id,
           route.id,
-          { req, res, eta },
+          { req, res, eta, notifications: req.notifications },
           req.session.userId,
         );
 
diff --git a/migrations/007_add_notifications.sql b/migrations/007_add_notifications.sql
new file mode 100644
index 0000000..c24462f
--- /dev/null
+++ b/migrations/007_add_notifications.sql
@@ -0,0 +1,20 @@
+-- Kernel-owned web-push subscriptions. A subscription is always scoped to the
+-- structure that registered it, and send-time fanout re-checks structure
+-- visibility before delivery.
+CREATE TABLE notification_subscriptions (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    structure_id INTEGER NOT NULL,
+    user_id INTEGER NOT NULL,
+    endpoint TEXT NOT NULL,
+    client_id TEXT,
+    subscription TEXT NOT NULL,
+    content_encoding TEXT,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    FOREIGN KEY(structure_id) REFERENCES structures(id),
+    FOREIGN KEY(user_id) REFERENCES users(id),
+    UNIQUE(structure_id, endpoint)
+);
+
+CREATE INDEX idx_notification_subscriptions_structure
+    ON notification_subscriptions (structure_id, user_id);
diff --git a/public/js/bliss.js b/public/js/bliss.js
new file mode 100644
index 0000000..3442d3c
--- /dev/null
+++ b/public/js/bliss.js
@@ -0,0 +1,130 @@
+(function () {
+  if (window.Bliss) return;
+
+  function pageStructureId() {
+    return (
+      document.body?.dataset?.blissStructureId ||
+      document.querySelector("[data-bliss-structure-id]")?.dataset
+        ?.blissStructureId ||
+      null
+    );
+  }
+
+  function clientId() {
+    const key = "bliss:client_id";
+    let id = localStorage.getItem(key);
+    if (!id) {
+      id =
+        crypto.randomUUID?.() ||
+        String(Date.now()) + "-" + Math.random().toString(36).slice(2);
+      localStorage.setItem(key, id);
+    }
+    return id;
+  }
+
+  function b64ToU8(s) {
+    const pad = "=".repeat((4 - (s.length % 4)) % 4);
+    const raw = atob((s + pad).replace(/-/g, "+").replace(/_/g, "/"));
+    const a = new Uint8Array(raw.length);
+    for (let i = 0; i < raw.length; i++) a[i] = raw.charCodeAt(i);
+    return a;
+  }
+
+  async function registration() {
+    if (!("serviceWorker" in navigator)) {
+      throw new Error("Service workers are not supported here.");
+    }
+    return navigator.serviceWorker.register("/_bliss/notification-sw.js");
+  }
+
+  async function postVisibility(state) {
+    if (!("serviceWorker" in navigator)) return;
+    const reg = await registration().catch(() => null);
+    reg?.active?.postMessage({
+      type: "bliss:visibility",
+      state,
+      structureId: pageStructureId(),
+    });
+  }
+
+  document.addEventListener("visibilitychange", () => {
+    postVisibility(document.visibilityState === "visible" ? "open" : "closed");
+  });
+  if (document.readyState === "loading") {
+    document.addEventListener(
+      "DOMContentLoaded",
+      () => postVisibility("open"),
+      {
+        once: true,
+      },
+    );
+  } else {
+    postVisibility("open");
+  }
+
+  window.Bliss = {
+    structureId: pageStructureId,
+    clientId,
+    notifications: {
+      supported() {
+        return (
+          "serviceWorker" in navigator &&
+          "PushManager" in window &&
+          "Notification" in window
+        );
+      },
+      permission() {
+        return "Notification" in window ? Notification.permission : "denied";
+      },
+      async register(options = {}) {
+        const structureId = options.structureId || pageStructureId();
+        if (!structureId) throw new Error("No Bliss structure is active.");
+        if (!this.supported()) {
+          throw new Error("Push notifications are not supported here.");
+        }
+
+        const reg = await registration();
+        if (Notification.permission !== "granted") {
+          const permission = await Notification.requestPermission();
+          if (permission !== "granted") {
+            throw new Error("Notification permission was not granted.");
+          }
+        }
+
+        const vapidResponse = await fetch("/_bliss/notifications/key");
+        if (!vapidResponse.ok) {
+          throw new Error("Could not load notification key.");
+        }
+        const { publicKey } = await vapidResponse.json();
+        const sub =
+          (await reg.pushManager.getSubscription()) ||
+          (await reg.pushManager.subscribe({
+            userVisibleOnly: true,
+            applicationServerKey: b64ToU8(publicKey),
+          }));
+
+        const ua =
+          String(navigator.userAgent || "") +
+          " " +
+          String(navigator.platform || "");
+        const isKaiOS = /kaios/i.test(ua) || !!navigator.b2g;
+        const response = await fetch("/_bliss/notifications/subscribe", {
+          method: "POST",
+          headers: { "Content-Type": "application/json" },
+          body: JSON.stringify({
+            structure_id: structureId,
+            client_id: clientId(),
+            subscription: sub,
+            content_encoding: isKaiOS ? "aesgcm" : "aes128gcm",
+          }),
+        });
+        if (!response.ok) {
+          const detail = await response.text().catch(() => "");
+          throw new Error(detail || "Could not register notifications.");
+        }
+        await postVisibility("open");
+        return true;
+      },
+    },
+  };
+})();