An ESP32 with its own domain, with no server in the middle. Is it possible?
The question has appeared in automation forums since 2023: can a microcontroller open a Cloudflare tunnel by itself and appear on the internet at its own address, without a Raspberry Pi in the middle and without opening a router port? The community's answer was always the same — “I don't think the ESP32 is powerful enough”.
“A Cloudflare tunnel running inside an ESP32, with no computer in the middle and without opening a router port.”
Why the question exists
A device behind a customer's router has no address visible from outside. Every known way to reach it charges something — money, exposure or the customer's IT team's goodwill.
Open a router port
Exposes the equipment to the entire internet and depends on a fixed IP, which carriers almost never provide.
A bridge machine
A Raspberry Pi or mini-PC running 24 hours beside the sensor, only to act as an intermediary.
Manufacturer cloud
Easy to start, but the data lives on a third-party server, with a subscription and changing rules.
VPN
Works well, but requires changing the customer's network — and almost no customer allows that.
What changes is not the chip
It is the question. “How do I make the ESP32 run that program?” has no good answer — and probably never will, because the official client was written for a complete operating system.
But a program and a protocol are not the same thing. One is heavy; the other is not necessarily. There is a space between the two — and that is where this project lives.
The method is not published, and that is intentional. This text records that it exists and works; it is not a tutorial and contains no code. What comes next is a series about the problem — why it was considered impossible and what changes when it is not.
The field this opens
It is not about hosting a website. It is about what can fit into the budget of a small project.
Sensor with telemetry on its own domain
Temperature, vibration, consumption — data leaves the equipment and appears at an address that belongs to you, without passing through anyone's cloud.
Machine panel accessible from anywhere
The technician enters the address and sees the equipment, whether it is at the plant or in another state.
Installation without a network service visit
Plug it in, connect to Wi-Fi and it is accessible. Nobody needs to touch the customer's router.
A lightweight page online for almost nothing
A portfolio, a project page, a technical business card — served by the hardware itself.
What the bill requires
- ESP32-S3 boardone-time purchase
- Power and Wi-Fiwhat already exists
- Domain≈ R$ 45 / year
- Cloudflarefree plan
- Server, hosting or VPSnone
There is no hosting fee because there is no hosting. In exchange, the ceiling is low: few simultaneous visitors and lightweight pages. It does not replace a server for high traffic, and that is not the intention.
The proof is not in this text
It is in the link. It opens a normal page, on a normal domain with secure HTTPS and a browser lock — and no server behind it. The HTML comes from a microcontroller the size of a piece of gum, connected to a phone charger.
If the address does not respond, the device may be being updated — it is real hardware on a real workbench.