Shantel Walker, a Papa John’s employee and Fight for 15 organizer, is challenging tough working conditions faced by fast food and other low-wage workers.

It’s 6 p.m. on a summer evening and the residents of the Bedford-Stuyvesant neighborhood in Brooklyn, New York are winding down after another long week of work. At a concrete school playground surrounded by a mesh wire fence, a small group of kids plays in the amber light while the tinny song of an ice cream truck rings out over the frenzied yells of a pickup basketball game. While many of her neighbors are thinking about dinner and the night’s plans, Shantel Walker’s workday has not yet begun.

Walker arrives at the playground on a bicycle decorated with a Black Lives Matter bandana and “Fight for 15” stickers; Destiny’s Child plays from her makeshift boom box—a tablet with a shattered screen and a portable speaker system, all bungee-corded to some cardboard resting atop her bike. Dressed in a New York City Freedom Fighters T-shirt bearing the words “I can’t breathe,” an enormous wrap-around watch, and a bedazzled cross around her neck, she is all warmth and quick laughs.

Walker, who is 35, has worked for Papa John’s for the better part of two decades, and that experience has fundamentally shaped her beliefs, her identity, and now, her mission in life.

Rather than accept the unlivable wages and unpredictable scheduling that working in fast food often requires, Walker decided to try to make a positive change for herself and other workers like her. In 2013, she joined the Fight for 15—the nationwide advocacy movement that successfully won an increase in the minimum wage in New York City and elsewhere.

She now spends the little free time she has doing unpaid organizing work for Fast Food Justice and Fast Food Forward, two grassroots advocacy nonprofits geared to the needs of fast food industry workers.

Walker never thought she would spend adulthood behind the counter of a fast food joint. At an early age, she had plans for a career in electronics. “When I was a kid, I wanted to be a fiberoptic technician,” she says. “I was really into working with my hands, computer rebuilding. I took classes in high school.”