Example: To-do app

A full to-do feature: sign in, create/toggle/delete encrypted todos, and stay in sync across the user’s devices via the change feed. Plain TypeScript + minimal React — drop the data layer into any framework.

The data layer

src/todos.ts

import { Client } from "@muhkoo/connect";

export const client = new Client({
  apiKey: "mk_live_pk_…",
  // baseUrl defaults to the hosted accelerator (https://api.muhkoo.dev).
});

export interface Todo {
  title: string;
  done: boolean;
  createdAt: number;
}

const COLLECTION = "todos";

export async function listTodos(): Promise<Array<{ id: string } & Todo>> {
  const ids = await client.storage.list(COLLECTION);
  const items = await Promise.all(
    ids.map(async (id) => {
      const t = await client.storage.get<Todo>(COLLECTION, id);
      return t ? { id, ...t } : null;
    }),
  );
  return items
    .filter((t): t is { id: string } & Todo => t !== null)
    .sort((a, b) => a.createdAt - b.createdAt);
}

export async function addTodo(title: string): Promise<void> {
  const id = crypto.randomUUID();
  await client.storage.set<Todo>(COLLECTION, id, {
    title,
    done: false,
    createdAt: Date.now(),
  });
}

export async function toggleTodo(id: string): Promise<void> {
  const t = await client.storage.get<Todo>(COLLECTION, id);
  if (!t) return;
  await client.storage.set<Todo>(COLLECTION, id, { ...t, done: !t.done });
}

export async function removeTodo(id: string): Promise<void> {
  await client.storage.delete(COLLECTION, id);
}

The React component

src/Todos.tsx

import { useEffect, useState } from "react";
import { client, listTodos, addTodo, toggleTodo, removeTodo, type Todo } from "./todos";

export function Todos() {
  const [todos, setTodos] = useState<Array<{ id: string } & Todo>>([]);
  const [draft, setDraft] = useState("");

  const refresh = () => listTodos().then(setTodos);

  useEffect(() => {
    refresh();
    // Live-update when todos change on any of the user's devices.
    const off = client.storage.on("change", (e) => {
      if (e.collection === "todos") refresh();
    });
    return off;
  }, []);

  return (
    <section>
      <form
        onSubmit={async (e) => {
          e.preventDefault();
          if (!draft.trim()) return;
          await addTodo(draft.trim());
          setDraft("");
          refresh();
        }}
      >
        <input value={draft} onChange={(e) => setDraft(e.target.value)} placeholder="New todo…" />
        <button type="submit">Add</button>
      </form>

      <ul>
        {todos.map((t) => (
          <li key={t.id}>
            <label style={{ textDecoration: t.done ? "line-through" : "none" }}>
              <input type="checkbox" checked={t.done} onChange={() => toggleTodo(t.id).then(refresh)} />
              {t.title}
            </label>
            <button onClick={() => removeTodo(t.id).then(refresh)}>✕</button>
          </li>
        ))}
      </ul>
    </section>
  );
}

Signing in first

The component assumes a signed-in user. Wire login wherever your auth UI lives:

await client.auth.zk.login(username, password);
// …then mount <Todos />

What’s happening

• Every todo is encrypted on the device before storage — the server stores ciphertext keyed by a random id.
• storage.on('change') keeps every open tab/device in sync with no polling.
• There’s no server-side query, so we list() ids and fetch each. For a big list, keep a small plaintext index (see Storage → Querying).