Running a monitoring platform means transactional emails are not optional. Alert notifications, password resets, verification emails — if those fail, users notice immediately. When our Hostinger plan expired and took the bundled email service with it, we needed a fix the same day. This is how we set up Resend as a zero-cost replacement and why it has been working cleanly ever since.
Why Not Just Use Gmail SMTP?
It's the first thing most developers reach for. But Gmail SMTP has a 500 email per day limit on
free accounts, your "From" address shows an unprofessional via gmail.com tag, and Google has
been tightening SMTP access to the point where it randomly breaks with 2FA changes. It works fine
for personal use, not for a production platform where email reliability directly affects the user experience.
What you actually need is a proper transactional email service tied to your own domain. That is exactly what Resend provides.
What Is Resend?
Resend is a developer-first email API built specifically for transactional emails. Think of it like SendGrid but cleaner, simpler, and genuinely free for small to mid-sized projects.
The free tier gives you:
- 3,000 emails per month
- 100 emails per day
- 1 custom domain
- Full API and SMTP access
- Email delivery logs and analytics
For most early-stage platforms and indie projects, that covers everything comfortably.
Setting It Up Step by Step
Step 1: Create a Free Account
Go to resend.com and sign up. No credit card required. Takes about a minute.
Step 2: Add Your Domain
Inside the Resend dashboard, navigate to Domains and click Add Domain. Enter your domain,
for example yourdomain.com.
Resend generates three DNS records for you: SPF, DKIM, and DMARC. These are the authentication signals that tell mail servers your emails are legitimate and should land in the inbox.
Step 3: Update Your DNS Records
Log into wherever your domain is registered — Hostinger, GoDaddy, Namecheap, wherever — and open DNS Management. Add each record Resend provides as a copy-paste job. The Resend UI walks you through exactly where each one goes, so there is no guesswork involved.
Step 4: Verify the Domain
Click Verify in the Resend dashboard. DNS propagation typically takes 15 to 30 minutes. Once complete, you will see a green checkmark next to your domain.
Step 5: Generate Your API Key
Go to API Keys, create a new key, name it, and copy it somewhere safe immediately. Resend does not show it again after you navigate away.
Step 6: Integrate Into Your Application
Resend has official SDKs for most major languages and frameworks.
Python (FastAPI or any backend):
import resend
resend.api_key = "re_your_api_key"
params = {
"from": "hello@yourdomain.com",
"to": ["user@example.com"],
"subject": "You're in!",
"html": "<p>Welcome aboard, glad to have you here.</p>",
}
resend.Emails.send(params)
Node.js / TypeScript (Next.js or any Node environment):
import { Resend } from 'resend';
const resend = new Resend('re_your_api_key');
await resend.emails.send({
from: 'hello@yourdomain.com',
to: 'user@example.com',
subject: "You're in!",
html: '<p>Welcome aboard!</p>',
});
The Part That Surprised Us
Once the domain is verified, you can send from any prefix without any extra configuration.
hello@, support@, noreply@, alerts@, billing@ — all of them work out of the box.
You verify the domain once and every combination of that domain is ready to use.
For a monitoring platform that sends different email types from different addresses, this was genuinely useful.
Why These Emails Land in the Inbox
The SPF, DKIM, and DMARC records you added earlier are the reason. Most developers skip these when setting up email and then wonder why their messages end up in spam. These records cryptographically confirm that Resend is authorized to send on behalf of your domain, and spam filters trust that signal. On top of that, Resend manages its own sending infrastructure and IP reputation, so your emails are not sharing a sending IP with bulk marketing blasts.
Both together is why deliverability is solid from day one.
How We Use This at MonitorPlatform
The alert emails and account notifications you receive from MonitorPlatform — whether it's an uptime alert, SSL expiry warning, or a password reset — all go through exactly this setup. It runs reliably, costs nothing, and every email lands in the inbox.
If you are building something similar and need a clean transactional email setup without paying for separate email hosting, this is the stack we would recommend without hesitation.
Wrapping Up
The switch from broken hosted email to Resend took under 45 minutes including DNS propagation time. The cost is zero. If your email setup is currently tied to a hosting plan, or you are wrestling with unreliable SMTP, Resend is worth the hour it takes to set up.
MonitorPlatform is currently in its early stages and we are actively building and improving the platform. If you haven't tried it yet, we'd love to have you take a look and share your honest feedback. No pressure to upgrade anything — we're just genuinely curious whether it solves real problems for developers like you. Sign up here and let us know what you think.
