Notes, Reminders & To-Dos Inside a Calendar

01The Problem With Separate Apps

Most people in Nepal juggle three things: a calendar app in English dates, a notes app that knows nothing about Dashain, and a reminder app that can't express “every Purnima.”

The friction isn't any single app — it's the translation tax between them. You think in Bikram Sambat, your tools think in Gregorian, and you spend cognitive effort converting all day long.

02BS-Native Everything

The critical design decision: Bikram Sambat is the primary date system, not a display translation layer. When you set a reminder for “15 Ashoj,” it stores 15 Ashoj — not a Gregorian timestamp that gets converted back for display.

// A note is anchored to a BS date, not a JS Date
{
  id: "note_a7f3",
  bsDate: { year: 2083, month: 6, day: 15 },  // 15 Ashoj 2083
  adDate: "2026-10-01",   // derived, for sorting/sync
  title: "Exam form deadline",
  body: "...",
  tags: ["college"],
  updatedAt: 1759286400000
}

This matters more than it sounds. A birthday on 5 Mangsir should recur on 5 Mangsir every year — which lands on a different Gregorian date each time. Store it as Gregorian and the recurrence drifts. Store it as BS and it's correct forever.

03Local-First Architecture

Every write goes to local storage first, then syncs in the background. The UI never waits on the network.

async function saveNote(note) {
  // 1. Write locally — instant, always succeeds
  await localDB.notes.put({ ...note, syncState: "pending" });

  // 2. Update UI immediately
  renderNote(note);

  // 3. Sync in the background, retry on failure
  queueSync(note.id).catch(() => {
    // Stays "pending" — retried on next connection
  });
}

Conflict resolution

When the same note is edited on two devices, last-write-wins by updatedAt timestamp, but the losing version is kept as a revision rather than discarded. Silently destroying someone's writing is unforgivable.

04How Reminders Actually Work

Reminders are harder than they look because they need to fire reliably across three surfaces: the web app, the browser extension, and push notifications — while the user may have all, some, or none of them open.

// Never setTimeout — it dies with the page/worker
// Always the Alarms API for the extension
chrome.alarms.create(`reminder_${id}`, {
  when: firesAtMs
});

chrome.alarms.onAlarm.addListener(async (alarm) => {
  if (!alarm.name.startsWith("reminder_")) return;

  const reminder = await getStored(alarm.name);
  chrome.notifications.create({
    type: "basic",
    iconUrl: "icon-128.png",
    title: reminder.title,
    message: reminder.bsDateLabel  // "१५ असोज २०८३"
  });

  // Reschedule if recurring
  if (reminder.repeat) scheduleNext(reminder);
});

05Recurring Tasks

Repeats are expressed in BS terms, which makes patterns Nepali users actually need possible:

That last one is the differentiator. No mainstream calendar app can express “remind me every Purnima” — but for a lot of families in Nepal, that's a real recurring obligation.

06Privacy by Design

Notes contain the most private things people write — health worries, money problems, thoughts they haven't said aloud. So the architecture makes it structurally hard to misuse:

• Encrypted at rest — sensitive vaults use a passphrase that never leaves the device
• Zero-knowledge for the vault — I literally cannot read what's in a user's password or health vault
• No ad SDKs — there is no third-party analytics or advertising code in the app at all
• No data sales — the business model is optional premium, not surveillance

07What I'd Do Differently