Architecture

Why Cloudflare — and why it's worth it.

OhRelay is not built like a traditional mailbox product that stores your messages in another hosted inbox. It uses Cloudflare Email Routing, Workers, and DNS control to receive mail, resolve where it should go, and hand it off to your real inbox without turning OhRelay into the place where your mail lives.

That setup requires the domain to use Cloudflare DNS, even if the registrar stays somewhere else. Here's the full picture.

The requirement

What Cloudflare DNS actually means

When people say a domain is 'on Cloudflare DNS', they mean the domain's nameservers point to Cloudflare. This gives Cloudflare visibility into all DNS traffic for that domain — and lets OhRelay automate setup through the Cloudflare API.

What OhRelay configures automatically

When you add a domain, OhRelay uses the Cloudflare API to set up the pieces it needs on your behalf:

Email Routing rules so messages sent to your managed addresses enter the correct flow
A Cloudflare Worker that applies OhRelay's routing logic when mail arrives
DNS records such as MX, SPF, and other delivery-related entries required for setup

In the happy path, this finishes in about a minute without you editing a DNS panel. That's only possible because Cloudflare already controls DNS for the domain.

What would happen without it

The registrar is not the issue. The current requirement is that DNS must be hosted on Cloudflare. If the domain is not in the connected Cloudflare account, OhRelay cannot activate it because the product depends on Cloudflare Email Routing and Workers.

Keeping Cloudflare as the control plane lets OhRelay validate the zone, apply the correct records, and repair configuration changes later through the same API.

How it works

Your email never sits on our servers

A message arrives at your domain address

Someone sends an email to support@yourdomain.com. Because your domain's MX records point to Cloudflare, the email enters Cloudflare's global mail infrastructure.

A Cloudflare Worker processes it at the edge

Cloudflare runs a Worker on the message in real time. That Worker is deployed by OhRelay and handles the routing logic: it reads the destination address, resolves the correct working inbox, preserves the metadata needed for the reply path, and forwards the message on.

This processing happens on Cloudflare's distributed network close to where the message entered.

The email is forwarded, not stored as another mailbox

The Worker forwards the message to your working inbox and the routing step ends. OhRelay does not provide a hosted mailbox or long-term message archive for that mail flow. The message continues on to the inbox you already use.

The email arrives in your real inbox

The message lands in your Gmail, iCloud, or whatever inbox you configured. From here it's entirely yours — in your account, under your control.

Privacy

Why the architecture is lighter on mail custody

No separate OhRelay inbox

OhRelay is a routing layer, not another mailbox product. The goal is to move mail into the inbox you already trust, rather than creating a second place where messages need to live and be managed.

Your data stays in your accounts

All received mail lives in your Gmail, iCloud, or other inbox — indexed by Google or Apple, backed up by them, owned by you. OhRelay is a routing layer, not a mailbox.

Cloudflare's infrastructure, not ours

The edge processing runs on Cloudflare Workers. OhRelay deploys the routing logic, and Cloudflare runs the distributed infrastructure that receives the mail and invokes the Worker.

Built on a distributed network

Because OhRelay relies on Cloudflare's network rather than a single hosted mail server, the mail path is designed around Cloudflare's global routing and edge execution model.

Already at another registrar?

Moving to Cloudflare is easier than it sounds.

Cloudflare offers a free plan that includes DNS hosting. When you add a domain, Cloudflare typically scans and imports your existing DNS records so you can review them before switching nameservers.

You do not need to transfer domain registration to Cloudflare. In most cases, you keep the registrar where it is and only update the nameservers to point to Cloudflare.

Cloudflare DNS setup guide ↗ Back to Quick Start