From the blog · Page 2
How we build, what we learn, what we ship.
The 5 best email APIs for developers in 2026
The best email API depends on your job: SendGrid, Mailgun, Postmark, Resend, or AgenticEmail. An honest 2026 comparison for developers.
Mailgun webhook guide: events, Routes, and signature verification
A complete Mailgun webhook guide - event webhooks vs inbound Routes, the payload shape, HMAC signature verification in Node, retries, and testing.
Gmail webhook: how to get a real-time push when email arrives
Gmail has no native webhook. Here is how to build one with Gmail API push notifications and Cloud Pub/Sub, plus simpler alternatives for agents.
Transactional email API: the definitive guide for 2026
What a transactional email API is, how it differs from marketing email, and how to choose one - deliverability, webhooks, idempotency, and two-way replies.
What does queued mean in email? A plain-English guide
What does queued mean in email? A guide to the queued status in Gmail, Outlook, and on mail servers, plus how sending queues work for developers.
Noreply email addresses: what they are and why to stop using them
What a noreply email address is, why companies use noreply@, and the 2026 case against it - deliverability, trust, and the reply-capable alternative.
BCC in email: what it means and when to use it
BCC in email means blind carbon copy. Learn what BCC means, how it differs from CC, when to use it, and how to send BCC in Gmail, Outlook, and code.
Scoped API keys, WebSocket events, batch sending, scheduled sends, and SMTP
A big infrastructure drop: per-inbox scoped keys, a real-time WebSocket event stream, batch and scheduled sending, and an SMTP gateway for everything that speaks classic email.
Why AI agents need their own email infrastructure
Email is the universal API between businesses - and agents are terrible tenants in human inboxes. Why borrowing a Gmail account does not scale, and what agent-native email looks like.