---
title: sently handbook
description: Channel-delivery for email, SMS, WhatsApp, and push — one sender shape as channels grow.
icon: BookOpen
source: "README.md"
---

sently is the channel-delivery layer for the order confirmation email, the OTP SMS, and the device push that follow.
Apps call a channel sender; providers live in transports you can swap without rewriting send sites.

<Callout title="The one rule">
  Use `createMailer`, `createSmsSender`, `createWhatsAppSender`, or `createPushSender` in app code — never a vendor SDK as your application API.
</Callout>

## Quick start

<Steps>
  <Step title="Install">

```bash
bun add sently
```

  </Step>
  <Step title="Send with a channel sender">

```ts
import { createMailer } from "sently/mailer";
import { ResendTransport } from "sently/transports/resend";

const mailer = await createMailer({
  transport: new ResendTransport({
    apiKey: process.env.RESEND_API_KEY!,
  }),
});

const result = await mailer.send({
  from: "hello@example.com",
  to: "person@example.com",
  subject: "Welcome",
  text: "Thanks for joining.",
});
console.log(result.messageId);
```

  </Step>
</Steps>

## Channels

| Channel | Sender | Start here |
| --- | --- | --- |
| Email | `createMailer` / `createSMTPMailer` | [Email](/docs/channels/email) |
| SMS | `createSmsSender` | [SMS](/docs/channels/sms) |
| WhatsApp | `createWhatsAppSender` | [WhatsApp](/docs/channels/whatsapp) |
| Push | `createPushSender` | [Push](/docs/channels/push) |

Email factories are asynchronous. SMS, WhatsApp, and push factories return the sender synchronously; every `send` is async.

## Where next

| Path | When |
| --- | --- |
| [Get started](/docs/get-started) | Install, entrypoints, runtimes, migrate from Nodemailer |
| [Channels](/docs/channels) | Full sender docs + lifecycle hooks |
| [Transports](/docs/transports) | Provider list by channel |
| [Failover](/docs/guides/failover) | Retry inside a provider, then fail over |
| [Support matrix](/docs/get-started/support-matrix) | Supported vs Available for production |
| [Compare](/docs/guides/compare) | vs vendor SDKs, Nodemailer, Novu / Knock / Courier |
| [Stability](/docs/get-started/stability) | What is frozen at 1.x |

## Troubleshooting

<Accordions>
  <Accordion title="Is sently a notification platform like Novu or Knock?">
    No. It is the delivery layer. Preference centers, digests, workflows, and in-app inboxes sit on top — custom code or those tools. See [Compare](/docs/guides/compare).
  </Accordion>
  <Accordion title="Where should I send first?">
    Start with [Email](/docs/channels/email) or [Installation](/docs/get-started/installation), then open the channel page for SMS, WhatsApp, or push when you add that channel.
  </Accordion>
</Accordions>

## Next

<Cards>
  <Card title="Get started" href="/docs/get-started" />
  <Card title="Channels" href="/docs/channels" />
  <Card title="Support matrix" href="/docs/get-started/support-matrix" />
</Cards>