And that’s how a sticky note saved a robot. In real life, you can download the Adafruit Motor Shield library via the Arduino Library Manager (search "Adafruit Motor Shield") or from GitHub .

Leo nodded wisely, then handed her a crumpled sticky note. On it, he’d drawn a motor, a shield, and an arrow pointing to a link: adafruit.com/afmotor . Zara laughed, typed the URL into her phone’s browser, and—miraculously—the page loaded.

"fatal error: AFMotor.h: No such file or directory"

Her little brother, Leo, wandered in. "Robot broken?"

Mech's LEDs flickered once, then died.