Yes I am the guy who asked the question on the RTC DS3231 + RPi on github and thanks to MichaIng I succeed in connecting my DS3231 to the Rpi but it was not enough to automatically update the system time at startup before updating it via ntp.
To make it fully functional on my RPi I had to do the same kind of thing that vmiceli did.
If it can be useful for other RPi user, I followed the tutorial here : https://learn.adafruit.com/adding-a-rea ... t-rtc-time
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