VarboxMail LogoTechnical Documentation · Engine v2.4

Integrate high-speed email delivery into your distributed microservices with our lightweight Node.js SDK.

Stable Release
|
Updated: Feb 2026

Introduction

VarboxMail provides a low-latency gateway between your application logic and global email relays. Unlike traditional providers, we emphasize Protocol Isolation—ensuring your sensitive data remains within your specified infrastructure boundaries.

Technical Density

Atomic tracking of injection success, relay latency, and city-level geolocation data.

Zero-Trust Auth

Encrypted handshake between SDK nodes and Control Plane using rotating system tokens.

Quick Start

1

Install the SDK

terminal
1npm install varboxmail
2

Initialize the Engine

index.ts
1import { VarboxMail } from 'varboxmail';
2 
3const mail = new VarboxMail({
4 apiKey: 'sm_test_001x99...',
5 environment: 'production'
6});
7 
8await mail.send({
9 to: 'target@example.com',
10 subject: 'Engine Initialization Test',
11 html: '<h1>VarboxMail Node Active</h1>'
12});

Complex Payloads

Use the dynamic injection engine for high-volume templated email distribution.

bulk-injection.ts
1await mail.injectBatch({
2 templateId: 'campaign_alpha_prod',
3 redundancy: 3,
4 nodes: ['us-east', 'eu-west'],
5 recipients: [
6 {
7 email: 'alpha@user.com',
8 data: { name: 'Alpha' },
9 metadata: { priority: 'high' }
10 },
11 {
12 email: 'beta@user.com',
13 data: { name: 'Beta' }
14 }
15 ]
16});

Error Handling

⚠ Important

Always wrap SDK calls in a try-catch block to handle network isolation or token expiration.

error-handler.ts
1try {
2 await mail.verifyNodeConnection();
3} catch (error) {
4 if (error.code === 'VARBOX_AUTH_FAILED') {
5 console.error('AUTH FAILED');
6 }
7 // Trigger automatic relay failover
8 await mail.failoverToSecondaryRegion();
9}

Need help?

Our infrastructure team is available 24/7 on the global control plane.