Privacy-Preserving Active Learning for heritage language revitalization programs across multilingual stakeholder groups Introduction: When a Dying Language Met Differential Privacy Last spring, I found myself hunched over a laptop at 2 AM, staring at a dataset of 4,200 annotated sentences in Nahuatl — a language with roughly 1.7 million speakers, most of them elders, scattered across central Mexico. A community organization had reached out to me after reading one of my earlier a...