Any ESP32 with enough pins to drive relays should work. A pre-integrated dev board with relays can save some time.

With PlatformIO these are fetched automatically from the registry (see lib_deps in platformio.ini); with the Arduino IDE, install them by hand:

• ArduinoJson (bblanchon)
• DallasTemperature (milesburton)
• OneWire (paulstoffregen)
• Time (paulstoffregen)

Build and flash with PlatformIO (pins library versions, needs no header symlinks):

cd controller
pio run -t upload      # build + flash
pio device monitor     # serial console

The Makefile in this directory wraps the same commands for convenience (make upload, make monitor, make uploadfs) — see the HTTP helpers below.

Note: the controller board (esp32dev, /dev/ttyUSB0 by default) does not auto-enter the bootloader on some USB-serial adapters — hold BOOT / tap EN before pio run -t upload if the upload fails to start.

The UI is a single self-contained data/index.html — no jQuery/CDN dependencies, so it works fully offline on the device's own AP. It reads the C/F unit from the controller, so the toggle in the on-screen Settings dialog changes both the web and the touchscreen display.

Upload it (and initialize the SPIFFS partition) with pio run -t uploadfs, or make uploadfs, which flashes the data/ directory to the device.

Firmware update (/update), the filesystem editor (/edit, /list) and WiFi configuration (/configureWifi) are protected by HTTP Basic auth. Set OTA_AUTH_USER / OTA_AUTH_PASS in secrets.h (defaults to admin/admin if unset).

make upload-spiffs-via-http-inotifywait
This will automatically upload any changed files in data/ directory on save

• Set up WiFi SSID/Passwords in secrets.h (copy secrets.h.example). These credentials are for the AP on the controller, not your home network.
• Connect to this network with your phone or laptop
• Browse to http://192.168.4.1
• Click the tiny gear button in the bottom-right corner
• The controller will reboot. Disconnect from the temporary network.