@ecosy/mailer

A production-ready email engine with a declarative template system, automatic retry with exponential backoff, and sliding-window rate limiting.

Features

• Template engine — Variables, components, conditionals (with operators), and loops
• Retry — Automatic retry with exponential backoff
• Rate limiting — Sliding-window with concurrent or serial execution
• Zero peer dependencies — Standalone package, no external runtime deps

Installation

yarn add @ecosy/mailer

Quick Start

import { Mailer } from '@ecosy/mailer';
import nodemailer from 'nodemailer';

const mailer = Mailer.from({
  driver: nodemailer,
  options: {
    host: 'smtp.example.com',
    port: 587,
    auth: { user: 'user', pass: 'pass' },
    from: '[email protected]',
    to: '[email protected]',
    subject: 'Hello {user.name}',
    content: '<p>Welcome, {user.name}!</p>',
  },
  data: { user: { name: 'Alice' } },
  retry: { retries: 2, delay: 1000 },
  rateLimit: { maxRequests: 5, interval: 1000 },
});

await mailer.send();

Template Syntax

| Directive | Syntax | Description | |-----------|--------|-------------| | Variable | {user.name} | Deep path interpolation | | Component | {@component:header} | Include named template | | Condition | {@if:user.isAdmin}...{@endif:user.isAdmin} | Truthy check | | Comparison | {@if:user.age >= 18}...{@endif:user.age} | Operator check | | Else | {@else:user.isAdmin} | Else branch | | Loop | {@loop:items}...{@endloop:items} | Array iteration |

Documentation

Full API reference and guides: docs.ecosy.io

License

MIT