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Transactional email, explained properly

Field guides on the things that actually decide whether a password reset, verification code or receipt reaches the inbox — authentication, deliverability, webhooks and provider integration. Every article ships with runnable code and a short answer up front.

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SMTP relay & migration Latest

587 vs 465: Which SMTP Port Should You Use?

Port 587 with STARTTLS or 465 with implicit TLS? Both are encrypted and correct for sending app email. The real difference, why to avoid port 25, and how to choose.

· 8 min read
Delivery events & webhooks September 2026 10 min

Build a Bounce & Complaint Handler That Protects Reputation

Ignoring bounces and complaints is how good senders quietly ruin their reputation. How to build a handler that suppresses the right addresses and keeps your

Authentication & OTP email September 2026 8 min

Choosing an OTP Code Expiry That Survives Email Delays

Set OTP expiry too short and email latency locks out real users; too long and you widen the attack window. How to choose a code TTL that balances security and

Deliverability for app email September 2026 11 min

DMARC Rollout Without Breaking Your Mail

Jumping straight to p=reject blocks your own transactional email. The staged none → quarantine → reject rollout — updated for DMARCbis, which removes the pct tag.

Deliverability for app email September 2026 10 min

Gmail & Yahoo Rules: What Applies to Transactional Mail

The 2024 Gmail and Yahoo sender rules were aimed at bulk mail — but parts apply to your transactional email too, and one part surprises everyone. What actually

Email API integration September 2026 10 min

Handling 429s: Backoff and Queue Design for Sends

A 429 from your email API isn't an error to swallow — it's a signal to slow down and retry safely. How to build backoff, jitter, idempotency and a queue that

SMTP relay & migration September 2026 10 min

Migrating to Notifiva Without Downtime

Switching transactional email providers scares teams because a botched cutover means lost password resets. A staged, no-downtime migration plan from SendGrid, SES

Email API integration September 2026 8 min

Test Email Flows Without Sending Real Mail

Testing email against production leaks messages to real users and dents your reputation. How to use sandbox keys, seed addresses and CI to test transactional flows

Delivery events & webhooks September 2026 9 min

Verifying Signed Webhooks: Why and How

An unverified webhook endpoint is an open door — anyone who finds the URL can forge events. How webhook signatures work, why raw-body and replay checks matter, and

Deliverability for app email September 2026 10 min

Why Transactional Mail Lands in Spam — and the Fixes

Your receipts and password resets are ending up in spam. Here are the causes that actually matter — authentication, reputation, content — ranked by how much they

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Put these patterns to work

Send your first transactional email with Notifiva — REST API or SMTP relay, with delivery webhooks and per-message logs included.