In January 2022, together with the Petrópolis City Hall, we responded to the tragedy: 240 deaths in the heavy rains of February. Fourteen days after the event, the Petrópolis Civil Defense was activated and warned that the heaviest rainfall in the country's history was approaching. We helped build a telemetry system to monitor Morro 24 de Maio, where a 9-ton rock was threatening lives. Four days after installation, a historic 530mm storm surge, including a landslide, led to evacuations and saved 51 people, with great pride, as the hill actually collapsed that night. Our work proved that technology saves lives, strengthens cities, and promotes resilience.