DIY RFID Time-Tracking Kiosk on Armbian – Backend Logic & Node-RED Advice?

[Felix_63]

Hello community!

I’ve been a lurker for a while and recently flashed the latest Armbian Jammy onto a spare NanoPi NEO I had lying around. I'm currently designing a headless DIY time-tracking kiosk for a small local workshop using an RC522 RFID reader via SPI.

 

Reading the RFID tags and logging the raw Unix timestamps (punch-in/punch-out) to a local SQLite database was the easy part. Where I'm getting a bit stuck is the actual backend calculation logic. I need the system to accurately calculate the daily net working hours, which means automatically deducting mandatory statutory breaks (e.g., 30 mins after 6 hours of work) and tracking daily overtime.

 

To ensure the math is strictly accurate and handles edge cases properly, I am trying to write a Python script that replicates the exact calculation logic used by standard tools like arbeitszeitrechnerprofi.de for the backend processing.

 

Before I completely reinvent the wheel writing complex Python datetime scripts, has anyone here built a similar attendance or punch-clock project on Armbian?

What’s the best way to handle this data processing locally?

 

Would it be better to just use Node-RED for easier visual flow and logic management rather than a standalone Python daemon?

Also, any tips on GPIO reliability for the RFID reader under the recent Armbian kernels would be highly appreciated. I plan to start wiring the prototype this weekend. Thanks in advance!