Installation

Install the Firmngin Arduino library on firmware projects that target ESP32 or ESP8266. [image:Arduino IDE and PlatformIO setup screen for Firmngin library]

PlatformIO

Add the library to platformio.ini.

[env:esp32dev]
platform = espressif32
board = esp32dev
framework = arduino
monitor_speed = 115200
lib_deps =
  firmngin/firmngin

The library uses PubSubClient for MQTT. The Firmngin Arduino repository vendors PubSubClient under the library source, so a separate install is normally not needed.

Arduino IDE

Use one of these install paths:

Install firmngin from Arduino Library Manager when available.
Download the latest release ZIP from the GitHub repository and install it with Sketch -> Include Library -> Add .ZIP Library.

Device credentials

Each Firmngin device needs a keys.h file next to the sketch. Download it from the Firmngin dashboard by opening the device in Device Registry, then using the device secrets download action. keys.h contains the device ID, device key, certificates, and validation mode used for secure connection.

Do not commit keys.h to version control. It contains device credentials and private key material.

Validation mode

The public template supports two validation modes:

Mode	Recommended use	Notes
CA certificate	ESP32 and production firmware	Stronger validation and safer certificate renewal behavior.
Fingerprint	ESP8266 or prototypes	Lighter, but must be updated when the server certificate changes.

First connection checklist

Install the library.
Add keys.h next to the sketch.
Configure Wi-Fi credentials.
Include firmngin.h and keys.h.
Construct Firmngin with DEVICE_ID and DEVICE_KEY.
Call begin() in setup().
Call loop() continuously in loop().

#include "keys.h"
#include <firmngin.h>

#if defined(ESP8266)
#include <ESP8266WiFi.h>
#elif defined(ESP32)
#include <WiFi.h>
#endif

const char *ssid = "YOUR_SSID";
const char *password = "YOUR_PASSWORD";

Firmngin fngin(DEVICE_ID, DEVICE_KEY);

void setup() {
  Serial.begin(115200);

  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }

  fngin.setDebug(true);
  fngin.begin();
}

void loop() {
  fngin.loop();
}

Getting started

Core concepts

Monetization

Libraries

PlatformIO

Arduino IDE

Device credentials

Validation mode

First connection checklist

​PlatformIO

​Arduino IDE

​Device credentials

​Validation mode

​First connection checklist

PlatformIO

Arduino IDE

Device credentials

Validation mode

First connection checklist