Send email with Amazon SES
Transactional email is the mail your app sends one recipient at a time — receipts, password resets, magic links, notifications. This guide sends one through Amazon SES, over both the API and SMTP, then shows the same send on MailKite.
What you'll need
- A domain you control, with access to its DNS records.
- An AWS account with Amazon SES, plus production access so you can send to any recipient.
- AWS credentials for the API, or a set of SMTP credentials for the SMTP interface.
Part 1 — Send with Amazon SES
1. Verify your domain
In the SES console, under Configuration → Identities, create a
domain identity. SES generates three Easy DKIM keys; publish the three
CNAME records it shows you so SES can confirm you own the domain
and sign your mail:
Type Name Value
CNAME abc123._domainkey.yourdomain.com abc123.dkim.amazonses.com
CNAME def456._domainkey.yourdomain.com def456.dkim.amazonses.com
CNAME ghi789._domainkey.yourdomain.com ghi789.dkim.amazonses.com The exact tokens are shown per identity in the console — copy them from there. New accounts also start in the SES sandbox, which only sends to verified addresses; to reach any recipient you must request production access for the account.
2. Send over the API
The SES API v2 send endpoint is
POST https://email.<region>.amazonaws.com/v2/email/outbound-emails.
Every request has to be signed with AWS Signature Version 4,
so most people call it through an AWS SDK or the CLI, which handle the
signing for you. Here it is with the CLI — the from address must
be on the domain you just verified:
aws sesv2 send-email \
--from-email-address hello@yourdomain.com \
--destination ToAddresses=ada@example.com \
--content '{
"Simple": {
"Subject": { "Data": "Your invoice #1042" },
"Body": { "Html": { "Data": "<p>Thanks! Your receipt is attached.</p>" } }
}
}' The response returns a MessageId:
{ "MessageId": "0100018f2c9a1b4e-3f7a…-000000" } 3. Or send over SMTP
Prefer SMTP? Point your app at the SES SMTP endpoint,
email-smtp.<region>.amazonaws.com, on port 587 with
STARTTLS. The username and password are SMTP credentials —
generated in the SES console and derived from an IAM user, not your AWS
access keys:
Host: email-smtp.us-east-1.amazonaws.com
Port: 587 # STARTTLS
Username: AKIA… # SMTP username — generated in the SES console
Password: B… # SMTP password — derived from an IAM user
From: hello@yourdomain.com That's a transactional send on Amazon SES: verify the domain, request production access, then call the signed API or the SMTP interface.
Part 2 — The same, on MailKite
When we built sending into MailKite, we wanted three things to be true: a plain bearer token instead of per-request SigV4 signing, no sandbox to apply your way out of, and one API key that's also your SMTP password — no separately-derived credential. Here's the same message.
1. Authenticate your domain
Publish three TXT records — SPF, a MailKite DKIM key, and DMARC.
The same domain also receives mail once its MX points at MailKite:
Type Name Value
TXT yourdomain.com v=spf1 include:mailkite.dev ~all
TXT mailkite._domainkey.yourdomain.com v=DKIM1; k=rsa; p=…
TXT _dmarc.yourdomain.com v=DMARC1; p=none; The exact DKIM value is shown in the dashboard; MailKite verifies the records for you over DNS.
2. Send over the API
One POST /v1/send with a flat from/to/
subject/html body. A 202 means it's
queued:
Pick your language in the card — the dashboard and the AI assistant do the same send, and every SDK takes the same fields:
Messages → Compose
From hello@myapp.ai
To ada@example.com
Subject Your invoice #1042
Body Thanks! Receipt attached.
Click [ Send ]Email ada@example.com from hello@myapp.ai
with subject "Your invoice #1042" and body "Thanks! Receipt attached."import { MailKite } from "mailkite";
const mk = new MailKite(process.env.MAILKITE_API_KEY);
const { id, status } = await mk.send({
from: "hello@myapp.ai",
to: "ada@example.com",
subject: "Your invoice #1042",
html: "<p>Thanks! Receipt attached.</p>",
});import os
from mailkite import MailKite
mk = MailKite(os.environ["MAILKITE_API_KEY"])
res = mk.send({
"from": "hello@myapp.ai",
"to": "ada@example.com",
"subject": "Your invoice #1042",
"html": "<p>Thanks! Receipt attached.</p>",
})<?php
$mk = new \MailKite\Client(getenv('MAILKITE_API_KEY'));
$res = $mk->send([
'from' => 'hello@myapp.ai',
'to' => 'ada@example.com',
'subject' => 'Your invoice #1042',
'html' => '<p>Thanks! Receipt attached.</p>',
]);MailKite mk = new MailKite(System.getenv("MAILKITE_API_KEY"));
Object res = mk.send(Map.of(
"from", "hello@myapp.ai",
"to", "ada@example.com",
"subject", "Your invoice #1042",
"html", "<p>Thanks! Receipt attached.</p>"
));mk := mailkite.New(os.Getenv("MAILKITE_API_KEY"))
res, err := mk.Send(mailkite.Message{
From: "hello@myapp.ai",
To: "ada@example.com",
Subject: "Your invoice #1042",
HTML: "<p>Thanks! Receipt attached.</p>",
})require "mailkite"
mk = Mailkite::Client.new(ENV["MAILKITE_API_KEY"])
res = mk.send(
"from" => "hello@myapp.ai",
"to" => "ada@example.com",
"subject" => "Your invoice #1042",
"html" => "<p>Thanks! Receipt attached.</p>"
)curl https://api.mailkite.dev/v1/send \
-H "Authorization: Bearer $MAILKITE_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"from": "hello@myapp.ai",
"to": "ada@example.com",
"subject": "Your invoice #1042",
"html": "<p>Thanks! Receipt attached.</p>"
}' Messages → Sent
● queued msg_2Hk9… ada@example.com Your invoice #1042Sent — message msg_2Hk9…, status queued.← 202 Accepted
{ "id": "msg_2Hk9…", "status": "queued" }← 202 Accepted
{ "id": "msg_2Hk9…", "status": "queued" }← 202 Accepted
{ "id": "msg_2Hk9…", "status": "queued" }← 202 Accepted
{ "id": "msg_2Hk9…", "status": "queued" }← 202 Accepted
{ "id": "msg_2Hk9…", "status": "queued" }← 202 Accepted
{ "id": "msg_2Hk9…", "status": "queued" }← 202 Accepted
{ "id": "msg_2Hk9…", "status": "queued" } 3. Or send over SMTP
The same key is your SMTP password — no separate credential to generate:
import nodemailer from "nodemailer";
const tx = nodemailer.createTransport({
host: "smtp.mailkite.dev",
port: 587, // STARTTLS · use 465 for implicit TLS
auth: {
user: "mailkite", // any username works
pass: process.env.MAILKITE_API_KEY, // your mk_live_… key
},
});
await tx.sendMail({
from: "hello@myapp.ai", // an address on a verified domain
to: "ada@example.com",
subject: "Your invoice #1042",
html: "<p>Thanks! Receipt attached.</p>",
});import os, smtplib
from email.message import EmailMessage
msg = EmailMessage()
msg["From"] = "hello@myapp.ai" # an address on a verified domain
msg["To"] = "ada@example.com"
msg["Subject"] = "Your invoice #1042"
msg.set_content("Thanks! Receipt attached.")
# Standard library — no dependency to install.
with smtplib.SMTP("smtp.mailkite.dev", 587) as s:
s.starttls()
s.login("mailkite", os.environ["MAILKITE_API_KEY"]) # password = your key
s.send_message(msg)<?php
use PHPMailer\PHPMailer\PHPMailer;
$mail = new PHPMailer(true);
$mail->isSMTP();
$mail->Host = 'smtp.mailkite.dev';
$mail->SMTPAuth = true;
$mail->Username = 'mailkite'; // any username
$mail->Password = getenv('MAILKITE_API_KEY'); // your mk_live_… key
$mail->SMTPSecure = PHPMailer::ENCRYPTION_STARTTLS;
$mail->Port = 587; // or 465 for implicit TLS
$mail->setFrom('hello@myapp.ai'); // an address on a verified domain
$mail->addAddress('ada@example.com');
$mail->Subject = 'Your invoice #1042';
$mail->Body = 'Thanks! Receipt attached.';
$mail->send();Properties p = new Properties();
p.put("mail.smtp.host", "smtp.mailkite.dev");
p.put("mail.smtp.port", "587"); // 465 for implicit TLS
p.put("mail.smtp.auth", "true");
p.put("mail.smtp.starttls.enable", "true");
Session s = Session.getInstance(p, new Authenticator() {
protected PasswordAuthentication getPasswordAuthentication() {
// username = anything · password = your mk_live_… key
return new PasswordAuthentication("mailkite", System.getenv("MAILKITE_API_KEY"));
}
});
Message msg = new MimeMessage(s);
msg.setFrom(new InternetAddress("hello@myapp.ai")); // a verified domain
msg.setRecipients(Message.RecipientType.TO, InternetAddress.parse("ada@example.com"));
msg.setSubject("Your invoice #1042");
msg.setText("Thanks! Receipt attached.");
Transport.send(msg);auth := smtp.PlainAuth("", "mailkite", os.Getenv("MAILKITE_API_KEY"), "smtp.mailkite.dev")
msg := []byte("From: hello@myapp.ai\r\n" + // an address on a verified domain
"To: ada@example.com\r\n" +
"Subject: Your invoice #1042\r\n\r\n" +
"Thanks! Receipt attached.\r\n")
// STARTTLS on 587; SendMail upgrades the connection before AUTH.
err := smtp.SendMail("smtp.mailkite.dev:587", auth,
"hello@myapp.ai", []string{"ada@example.com"}, msg)require "mail"
Mail.defaults do
delivery_method :smtp, {
address: "smtp.mailkite.dev",
port: 587, # 465 for implicit TLS
user_name: "mailkite", # any username
password: ENV["MAILKITE_API_KEY"], # your mk_live_… key
enable_starttls_auto: true,
}
end
Mail.deliver do
from "hello@myapp.ai" # an address on a verified domain
to "ada@example.com"
subject "Your invoice #1042"
body "Thanks! Receipt attached."
end See Send API and SMTP relay for the full reference — attachments, headers, and delivery events.
A little about MailKite
MailKite is programmable email for developers and AI agents. One API key and
one set of DNS records cover both directions: send with a single
POST (or the SMTP relay), and the same verified domain receives
replies as a signed webhook of clean JSON.
Behind the send, MailKite routes across multiple providers to keep you in the
inbox — and any address can be handed to an agent
that reads and replies on its own. Sending and receiving are on the
free tier.
Next: the Send API for attachments and delivery tracking, or the Quickstart to get a verified domain and API key.