The espresso machine was warming up and Liliia Korneva was counting cash at the coffee shop in Kharkiv where she works when a powerful Russian bomb detonated nearby, sending up a deafening explosion and knocking her to the floor.

“I can’t describe in words how it felt, it was terrifying,” said Ms. Korneva, 20. She was not hurt, though the courtyard where the bomb fell was destroyed and a man riding a bicycle nearby was killed, according to city officials.

Just a day later, the cafe was open again. Kharkiv, Ukraine’s second largest city, is open for business, too, despite a sustained bombing campaign that is among the most devastating of the entire war and growing fears that Russia might launch a renewed offensive aimed at taking the city.

Russian attacks have destroyed all three major power stations, but residents continue to live and work with only a few, often unpredictable, hours of electricity each day. More than 100 schools have been damaged or destroyed but classes go on, deep underground in subway stations. Dozens of fire and paramedic stations have been blown up, putting first responders in daily jeopardy but failing to deter them from their jobs.