At two in the morning, the device stopped giving raw traces and instead offered a test harness. When Mara ran the harness, the board blinked its LED in a pattern that matched an old lullaby her grandmother used to hum. Her heartbeat sped. She scrolled through the mapped memory and found a block of annotated strings — names, dates, a place: "Shipyard 17 — spring, '09." A picture of hands at a soldering iron floated to mind: heavy hands stained with flux, careful hands that cared.