The circuitry for this one is much simpler, due to it being an IoT project and not a stand-alone datalogging project.  As the internet already knows the time we don't need an RTC, and as Blynk logs data we don't need an SD card reader.  

I decided to use the Sparkfun Photon battery shield, as I want this to be battery powered and it contains a "fuel gauge" chip in it.  For $13 it seems like a very convenient solution.

This shield has the pins broken out for soldering.  I just needed to wire up 2 photo-interrupters and attach them to 3.3V, GND, and D2/D3 (left/right).  And then plug in a battery.

More detailed schematics coming, but that's it for the hardware!