Posted identically in the Home Assistant Community
The more I work on sophisticated automations, the more I realise that neither YAML, Jinja, Helpers, Home Assistant’s visual editor nor Homey’s Advanced Flow are the real challenge.
The real challenge is complexity — and trying to foresee every possible interaction and edge case.
My roller shutter system is a good example.
It has several operating modes:
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Manual
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Manual (temporary)
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Sun protection
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TV
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Sun protection + TV
And each mode behaves differently.
The sun-protection logic doesn’t simply check whether the sun is shining. Depending on the window, it evaluates solar azimuth, solar elevation and luminance to determine whether that window actually needs protection.
On colder days, it becomes more complex. The system compares the temperature measured on the sun-exposed facade with a sensor in the shade. From the temperature difference, it estimates whether the sun currently has enough heating power to justify closing the shutter.
In bedrooms, the logic changes again depending on whether the window is open or closed.
With the window closed, the shutter primarily provides sun protection.
With the window open, indoor and outdoor temperatures are compared and the shutter effectively becomes part of the ventilation control, adjusting how much air exchange is possible.
There is also winter protection: if the room gets too cold while a window is open, the shutter closes completely to slow further cooling.
Then there are exceptional situations.
If a smoke alarm is triggered, all shutters open to clear possible escape routes. A central override prevents any other automation from closing them again while the alarm is active.
Manual operation also has priority. If somebody operates a shutter using the physical switch, that window changes to Manual (temporary) and normal automations leave it alone. At 03:00, it automatically returns to its previous mode.
All of this is already quite complex, and I honestly don’t think I could have built and maintained the complete logic without AI helping me analyse it.
But then my son found an edge case that neither I nor the AI had considered.
He was doing homework when the sun-protection automation started lowering the shutter. He didn’t want it closed, so he stopped it while it was moving and then raised it again manually.
A few minutes later, the shutter went down again.
Normally, manually moving a shutter should activate Manual (temporary) and prevent sun protection from touching it again.
So what happened?
The automation had marked the downward movement as an automatic movement. That flag was supposed to be cleared when the shutter reached its target position.
But my son interrupted the movement before it arrived there.
The flag therefore remained set.
When he subsequently raised the shutter manually, the system still believed that the movement belonged to the automation and did not activate Manual (temporary).
Technically, every part of the logic worked exactly as designed.
The problem was that we had never considered the sequence:
Automatic movement → manually interrupted → manual movement in the opposite direction.
We changed the logic so that interrupted movements are handled correctly as well.
And that brought me to what I now think is the real difficulty of sophisticated home automation:
Building the automation is not necessarily the hardest part. Foreseeing every possible state, interruption, timing issue and interaction between automations is.
AI helps enormously, but even AI doesn’t automatically think of every real-world situation that someone in the house may create.
So I’m curious how others approach this.
Do you also build increasingly sophisticated automation logic and deal with these edge cases as they appear?
Or do you deliberately keep your automations simpler and accept giving up some of the “ultimate” automation experience in exchange for easier maintenance and predictability?
