@profullstack/emailer

Mass emailer for Profullstack apps. Wraps Resend's batch API with a simple interface for sending bulk emails. Zero runtime dependencies.

Installation

npm install @profullstack/emailer

Usage

import { createEmailer } from '@profullstack/emailer';

const emailer = createEmailer({
  resendApiKey: process.env.RESEND_API_KEY,
});

Send a single email

const result = await emailer.send({
  from: 'App <[email protected]>',
  to: '[email protected]',
  subject: 'Hello',
  html: '<p>Hello world</p>',
  text: 'Hello world',
});

// { sent: true, id: 're_...' }

Send a bulk email

const result = await emailer.sendBulk({
  from: 'App <[email protected]>',
  to: ['[email protected]', '[email protected]', ...],
  subject: 'Big announcement',
  html: '<p>Something exciting</p>',
  text: 'Something exciting',
  batchSize: 100,  // default: 100 (Resend's batch limit)
  delayMs: 500,    // optional delay between batches
});

// { sent: 2, failed: 0, errors: [] }

Per-recipient personalization

Pass a function for html or text to customize per recipient:

await emailer.sendBulk({
  from: 'App <[email protected]>',
  to: emails,
  subject: 'Your weekly digest',
  html: (email) => `<p>Hi ${email}, here's your digest…</p>`,
});

API

createEmailer(config)

| Option | Type | Description | |---|---|---| | resendApiKey | string | Resend API key (required) | | defaultFrom | string | Default from address used when not provided per-call |

emailer.send(opts)

| Option | Type | Description | |---|---|---| | from | string | Sender (falls back to defaultFrom) | | to | string | Recipient | | subject | string | Subject line | | html | string | HTML body | | text | string? | Plain-text body | | replyTo | string? | Reply-to address | | headers | Record<string,string>? | Extra headers (e.g. List-Unsubscribe) | | attachments | Array<{filename,content}>? | Base64-encoded attachments |

Returns { sent: boolean, id?: string, error?: string }.

emailer.sendBulk(opts)

Same as send but to is string[], html/text can be a (email: string) => string function, plus:

| Option | Type | Default | Description | |---|---|---|---| | batchSize | number | 100 | Recipients per Resend batch call | | delayMs | number | 0 | Delay between batch calls |

Returns { sent: number, failed: number, errors: Array<{email, error}> }.

License

MIT © Profullstack Inc