Email infrastructure, sent the way a carrier actually delivers it.
A transactional email API for developers. One clean send() call - we handle authentication, deliverability, and every bounce, complaint, and unsubscribe on the way out.
What ZendMailer is
§ 01The short version, in plain language, for anyone about to ship their first ZendMailer send.
Transactional email your users actually asked for - password resets, receipts, magic links, notifications, order confirmations, invites. Not marketing blasts, not cold outreach.
Developers and small engineering teams who'd rather ship product than wire up raw SMTP or the AWS SDK. You get one API call and a dashboard - not a mail server to keep alive.
Every message rides on Amazon SES's delivery infrastructure - a warmed, reputation-managed pool trusted by every major mailbox provider. You get that deliverability without touching a single AWS console.
SPF, DKIM, DMARC setup on your sending domain. Automatic suppression on bounces and complaints. One-click unsubscribe on every non-security message. Real-time events streamed to your webhook.
How a message actually moves
§ 02Three things happen to every message you send - so it lands as "delivered," not just "submitted."
Verified before it sends
You verify your sending domain once by publishing our DKIM CNAME records. Until those records are live, we won't let anything go out from that domain - which is exactly what mailbox providers want to see.
Bounces stop the list
Hard bounces and complaints are suppressed automatically, within seconds - not on a nightly batch. That address won't get another message from you, which protects your reputation with every mailbox provider.
Unsubscribe is structural
Every non-critical message carries a one-click unsubscribe header (RFC 8058) and a footer link. Opting out removes the address at the account level - no per-campaign leakage, no re-adds through the back door.
Questions developers ask before signing up
§ 03Straight answers to the questions that come up when you're evaluating a new email provider.
01How do I get started?
Sign up, add a sending domain, and publish the DKIM CNAME records we give you at your DNS host. As soon as we confirm the records are live, you can generate an API key and send your first message. Most teams are sending within 15 minutes.
02What kinds of email can I send?
Transactional messages triggered by something your user did - account verification, password resets, magic links, receipts, invoices, order updates, shipping notifications, invites, and system alerts. We don't allow marketing blasts, cold outreach, or messages to purchased or scraped lists.
03How do you make sure messages actually reach the inbox?
Three things, running on every send:
- Full authentication (SPF, DKIM, DMARC) set up on your sending domain before your first message
- Delivery over warmed, reputation-managed IP pools trusted by every major mailbox provider
- Continuous bounce and complaint monitoring, with automatic suppression to keep your reputation clean
04What happens when a message bounces or someone marks it as spam?
Within seconds, we add that address to your account's suppression list and stop future sends to it - no matter which API key or template you use. You'll see the bounce reason and complaint feedback loop data in your dashboard immediately.
05Do I have to use my own sending domain?
Yes - and that's how you want it. Sending from your own domain is what makes your emails look legitimate to mailbox providers and to your users. We walk you through the DNS records and verify each one before enabling sending.
06How do I see what happened to a message after I sent it?
Every event - sent, delivered, bounced, complained, opened - is logged to your dashboard in real time and can be pushed to a webhook you configure. Search by recipient, message ID, or time window. Data is retained for 90 days.
07How do I get help if something breaks?
Email hello@zendmailer.com and a human on our team responds within one business day - usually much faster. If you're troubleshooting deliverability on a live domain, mention that and we'll prioritize it.
What you don't have to build
§ 04Four things ZendMailer handles for you on every send, so your team can stay focused on the product.
Domain authentication
SPF, DKIM, and DMARC set up on your sending domain - we verify every record before you send.
Automatic suppression
Bounced and complained addresses stop sending across your whole account, within seconds.
Deliverability monitoring
Per-domain bounce and complaint rates tracked continuously, with alerts before problems compound.
Real-time events
Every send, delivery, bounce, complaint, and open streamed to your webhook and dashboard.
Ready to send your first message?
Get on the ZendMailer waitlist. We'll walk you through domain setup, get you an API key, and have your first message delivering in minutes.