---
title: Bundle size
description: Keep imports focused on the channel and transport your app actually uses.
icon: PackageOpen
source: "package.json"
---

sently is split into subpaths so a receipt mailer does not pull SMS, SMTP pooling, or unused providers.
Measure stacks with `bun run measure:size` in the library repo when you change imports.

<Callout title="The one rule">
  Import channel senders and provider transports from subpaths — never from a convenience barrel
  when a focused path exists.
</Callout>

## Quick start

<Steps>

<Step>
### Prefer mailer + one transport

```ts
import { createMailer } from "sently/mailer";
import { SndrTransport } from "sently/transports/sndr";

const mailer = await createMailer({
  transport: new SndrTransport({ apiKey: process.env.SNDR_API_KEY! }),
});
```

</Step>

<Step>
### Prefer one webhook parser

```ts
import { parse, verifySignature } from "sently/webhooks/sndr";
```

Avoid `import { … } from "sently/webhooks"` in Node/Deno without a bundler — that barrel evaluates every provider module.

</Step>

</Steps>

## Typical stacks

| Stack | Imports | Notes |
| ----- | ------- | ----- |
| HTTP email (SNDR) | `sently/mailer` + `sently/transports/sndr` | Small HTTP path. |
| HTTP email (Resend) | `sently/mailer` + `sently/transports/resend` | Includes attachment helpers. |
| SMS | `sently/sms` + `sently/transports/twilio-sms` | Channel + one SMS transport. |
| SMTP | `sently/smtp` | Separate from `sently/mailer`. |

## Troubleshooting

<Accordions>

<Accordion title="Why did importing createMailer from sently get larger?">

With a bundler and `sideEffects: false`, unused re-exports usually shake out. Without a bundler, the main barrel still evaluates its static imports (SMTP factory, Fallback, Cloudflare Email, …). Prefer `sently/mailer` for HTTP-only apps.

</Accordion>

</Accordions>

## Learn more

- [Entrypoints](/docs/get-started/entrypoints) — which path to import
- [Exports](/docs/reference/exports) — full map

## Next

<Cards>
  <Card title="Entrypoints" description="Choose a focused import." href="/docs/get-started/entrypoints" />
  <Card title="SNDR" description="Small HTTP email transport." href="/docs/transports/sndr" />
</Cards>