# Migrate from Nodemailer (/docs/guides/migrate/nodemailer)



Email SDK includes its own SMTP transport. You do not need Nodemailer for basic address fields, text/HTML bodies, headers, TLS upgrade, and SMTP auth.

## Replace the transporter [#replace-the-transporter]

```ts title="after.ts"
import { createEmailClient } from "@opencoredev/email-sdk";
import { smtp } from "@opencoredev/email-sdk/smtp";

const email = createEmailClient({
  adapters: [
    smtp({
      host: process.env.SMTP_HOST!,
      port: Number(process.env.SMTP_PORT ?? 587),
      auth: {
        user: process.env.SMTP_USER!,
        pass: process.env.SMTP_PASS!,
      },
    }),
  ],
});
```

On a non-secure port, SMTP auth upgrades with STARTTLS by default. `allowInsecureAuth` exists only for trusted local test servers.

## Replace `sendMail` [#replace-sendmail]

```ts title="after.ts"
const result = await email.send(
  {
    from: "Acme <hello@acme.com>",
    to: "user@example.com",
    subject: "Welcome",
    text: "Your account is ready.",
    html: "<p>Your account is ready.</p>",
    headers: [{ name: "X-App", value: "acme" }],
  },
  { idempotencyKey: "welcome:user_123" },
);
```

The transport creates `multipart/alternative` for text plus HTML and derives `Message-ID` from the idempotency key.

## Account for unsupported features [#account-for-unsupported-features]

The built-in SMTP adapter rejects attachments, tags, metadata, and schedules. Keep Nodemailer or build a custom adapter if your SMTP workflow depends on MIME attachments or advanced transport plugins.

## Verify [#verify]

```bash
SMTP_HOST=smtp.example.com npx email-sdk doctor --adapter smtp
npx email-sdk send \
  --adapter smtp \
  --host smtp.example.com \
  --from hello@example.com \
  --to user@example.com \
  --subject "Migration smoke test" \
  --text "Dry run only." \
  --dry-run
```

<Card title="SMTP adapter" href="/docs/adapters/smtp" description="See TLS, auth, custom names, and transport limits." />