This piece marks my third by-line in Popular Science. It opens the “Manual” section of the October 2015 issue. Besides designing the circuit, writing the copy, and building the solder-free breadboard-based device shown in the photo, I also carved the pumpkin. Fun fact: Halloween magazine content has to be in bed in the summer, when nobody is selling pumpkins. There is, however, a high quality brand of carve-able fake pumpkin, called a Funkin, which is apparently the industry standard for this sort of thing. It carves easily with a special tool which is somewhere between a paring knife and a fine-tooth hacksaw.

I’m indebted to Lenore and Windell at Evil Mad Scientist Laboratories for the two circuits on which the electronics are based. My breadboard is really just a simple mash-up of their dark detecting jack-o’-lantern and solderless flickery flame designs. Their online store remains the best place to buy candle-flicker and other specialty LEDs in the known universe, as well as tons of other cool open-source electronics you can’t get anywhere else.

Here’s Popular Science Projects Editor Sophie Bushwick building the project on camera: