n8n is an open-source workflow automation platform that connects APIs, databases, and services. In practical terms, it allows non-programmers to build complex systems using a visual interface, while offering developers a powerful and scalable way to design automations. It's one of the most popular platforms for deploying AI agents, combining triggers, language models (LLMs), and external tools.
Recently, I was asked to come up with a few n8n projects, and I thought it’d be fun to create a small bridge between the digital and physical worlds: a simple hardware button that can trigger a workflow or node.
1. n8n wekhook
First, head to your n8n workflow and create a webhook node. Double-click the node to get the webhook URL.
2. Hardware
All you need is an ESP32 board. In my example, I’m using this one: Beetle ESP32-C3, but any ESP32 should work.
ESP32C3
You can either connect a push button between a free GPIO and GND, or use the onboard button that some ESP32 boards include. For the Beetle C3, the Boot button is mapped to GPIO 9 — so you can use that out of the box without soldering anything.
Image from last minute engineer
3. Button Software
ESP32N8NButton Library
In the Arduino IDE, install the ESP32N8NButton library.
Then go to Examples > ESP32N8NButton and edit the sketch with your Wi-Fi SSID and password, the webhook URL from step 1, and the GPIO pin your button is connected to. If you're using the onboard button, just set the corresponding GPIO pin.
Configure settings
Upload the sketch to the ESP32 — and that's it.
Usage
Every time you press the button, your n8n workflow is triggered. That could mean checking your calendar and sending a meeting slot via WhatsApp, pulling Tesla stock data, or anything else your automation handles.
Demo
https://x.com/RoniBandini/status/1934617385643778056
Final Notes
I’m not entirely sure yet where this kind of physical interface for n8n will be most useful. Maybe triggering backups, starting a home alarm, or launching some industrial process — all without needing to unlock your phone or computer. Either way, it’s a fun and simple project.
If you build your own version with a GPIO button and a nice case, send pics!
Links
https://github.com/ronibandini/ESP32N8NButton
