New to Raspberry Pi - I want to create a device which upon hearing a particular word it will activate/deactivate something. E.g. if I say the word "light", it will turn on/off an LED light. The device will only recognize this one and only word that I program it with. Hoping to use it at home which might have some background noise. 

The key part that I'm not sure how to implement is the voice recognition. Would open-source libraries like mycroft and jasper help with this, or is there any other solution? If I were to use it in a home setting with various background noises is rnnnoise the state-of-the-art noise cancelling technique or are the open-source packages enough?

Edit: Sorry I should've specified, I want this device to be disconnected from the internet, so using Alexa / Google would be off the table.