A real-world smart gate controller using an ESP32, relay module, and free-tier cloud services. No GSM, no subscriptions, no keypad. Just Wi-Fi and a clean web interface.

This system is deployed in a residential community and lets guests open a barrier using a 4-digit PIN through a mobile browser. Admins generate PINs from their phones. All logic is handled by a Cloudflare Worker backend. No hosting costs. Fully open-source.

Highlights:

  • ESP32 triggers a gate relay via Blynk Cloud

  • PINs validated by a secure Cloudflare Worker API

  • PINs stored with expiration in Cloudflare KV

  • Mobile-friendly React frontend (GitHub Pages)

  • Zero apps, zero cloud lock-in

Hardware:

  • ESP32 DevKit board

  • 5V relay module (dry contact)

  • Optional external antenna

  • Power source (USB or 5V DC)

Software:

  • Arduino firmware (ESP32 listens to Blynk Virtual Pin V0)

  • Cloudflare Worker (backend logic)

  • GitHub Pages-hosted frontend

  • Blynk Cloud (trigger API)

Live Guide & Source Code:
https://tinkeriot.com/esp32-smart-gate-access/

GitHub:
Backend + Firmware: https://github.com/tinkeriotops/esp32-barrier-be
Frontend (React): https://github.com/tinkeriotops/tinkeriotops.github.io

Support:
https://ko-fi.com/tinkeriot