Developer Guides
Step-by-step guides for email delivery, authentication, API integration, and deliverability optimization.
Getting Started
Email Authentication
Email Authentication Overview
How SPF, DKIM, and DMARC work together to protect your domain.
SPF Record Setup
Create and publish an SPF record to authorize your sending servers.
DKIM Setup
Generate DKIM keys and add the DNS record for message signing.
DMARC Setup Guide
Configure a DMARC policy to enforce authentication and get reports.
Deliverability
Email Deliverability Guide
Everything that affects whether your email reaches the inbox.
Improve Email Deliverability
Actionable steps to increase inbox placement rates.
Reduce Email Bounce Rate
Identify and fix the causes of hard and soft bounces.
Emails Going to Spam
Diagnose and fix spam folder placement issues.
Domain Reputation
How ISPs score your domain and what affects the score.
Domain Warmup
Gradually ramp sending volume on a new domain or IP.
Integration
Best Email API for Node.js
Compare email APIs for Node.js projects and pick the right one.
Best Email API for Python
Compare email APIs for Python projects and pick the right one.
SMTP Ports Explained
Which port to use for SMTP submission, relay, and encryption.
SMTP Error Codes
Reference for common SMTP response codes and what they mean.
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