Calido - Open-source Thermostat And Home Controller/monitor

About the project

Calido is a smart thermostat and smart-home controller and monitor. Accessible via HomeAssistant, or a wall-mounted connected screen You are able to monitor and (automatically or not) control the temperature, humidity and overall air quality inside your home. It will also be able to control other smart-home devices accordingly.

Project info

Difficulty: Difficult

Platforms: Home AssistantEdge ImpulseNordic Semiconductor

Estimated time: 3 days

License: Apache License 2.0 (Apache-2.0)

Items used in this project

Hardware components

Sensor Tool W nRF52840 & nRF9160 Sensor Tool W nRF52840 & nRF9160 Completely built with the Thingy:91 x 1
USB A To USB MICRO B 1M USB A To USB MICRO B 1M To connect and flash the Thingy:91 to your computer x 1

Software apps and online services

nRF Cloud nRF Cloud With the iBasis SIM card included with your Thingy91
nRF Connect for desktop nRF Connect for desktop To get nRF SDKs and Programmer
nRF Programmer nRF Programmer To flash your Thingy91
an MQTT broker an MQTT broker
Home Assistant Home Assistant


The project code can be found at

Built on a Thingy:91 (nRF9160).


Calido was built to monitor and control a house temperature, humidity, vibrations, overall air quality and its heating system, to control other smart-home devices and to notify the user.

It can send data via MQTT to Home Assistant for user monitoring and automations.

Calido can also use its BLE to fetch data from various external sensors.

Calido can send signal via its GPIOs to relays, for example to turn on and off home heating and cooling.

TinyML can be run on the device to learn and later predict the user's preferred home teperature based on time of day and outside climate.

Data can be sent to Edge Impulse to process it, it could for example be trained with vibrations data to predict earthquakes. This data could be massively crowdsourced in high seismic activity areas to help those regions or countries better predict and prevent future natural disasters.

Set up

  1. Update your Thingy:91's firmware (instructions here).

  2. Put your included iBasis SIM card in your Thingy:91, and register it in nRF Cloud (instructions here).

  3. Build the firmware

  4. Flash it onto your Thingy:91.

  5. Have your MQTT Broker up and linked to HomeAssistant

  6. Connect Edge Impulse (
    Get the Edge Impulse project at Calido's EI project page




Please be welcome to contribute at the project's Github repository.


Project licensed under  an Apache-2.0 license.

made/with/lots/of/lovely/ducks/🦆💖 ....... Lucas Placentino

Schematics, diagrams and documents


Calido's UI


Calido Github Repo

Calido's repository (on Github)


Photo of lplacent


Engineering student at ULB


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