I mainly find notifications on my mobile phone annoying and have disabled most of them. But things are different when something requires my attention at home. The classic example is the doorbell: I want to know when a delivery person is standing at my front door even if I'm flooding my noise-killing headset with electric guitar music. I already solved this problem back in 2016 with a Raspberry Pi and described the setup in this column [1].

With my earlier solution, notifications reached me as Twitter direct messages, mainly because I didn't want to install a notification app just for this purpose. Twitter is already installed on my phone and provides a useful programming interface. However, Twitter is increasingly setting up hurdles for access to the API. For example, you now need to describe in a small, free text essay the purpose of your proposed use of the API. This may be understandable from the supplier's point of view, but I would prefer things to be a little simpler.

This explains why I now use the Telegram API [2]. Among other things, I can create bots that can be used to do many funny things. On top of this, I can get the bot to send me messages. You can create a bot by starting a chat with BotFather in the Telegram app (Figure 1).

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