A jolly jingle electrifies the air in the parking lot at Thumpertown Beach in Eastham. Seconds later, Nicki Waite swings into view, driving her vintage ice cream truck: a 1973 Ford Grumman Olson, originally a Dairy Maid truck. Waite found the truck in disrepair in Brockton 20 years ago. “I rescued it,” she says. Now it’s sparkling clean, advertising Good Humor ice cream bars and Snow Cones, Bomb Pops and Popsicles, Creamsicles and King Size Cones.

Waite was born in Eastham and raised in Harwich. She’s been an “ice cream lady” since 1999, except for one summer five years in, when she worked as a manager and bartender at Luscious Louie’s, now closed. “I didn’t see the beach at all that summer,” she says. All she wanted was to be back on the road. She calls her operation “Good Times Cape Cod.”

She visits the bayside beaches of Eastham during the day and goes all over the Cape for private events after hours. Her customers are like family. “I’ve watched these people grow up, and they’ve watched me grow, too,” she says.

The children of Eastham are loyal to Good Times, she says. During her first season, she competed with another ice cream truck — a chain. When that truck came around, the kids who knew Good Times would “cross their arms and turn their backs in solidarity,” says Waite. After a few seasons, the other truck gave up, she says. “These little kids are ride-or-dies, they’re Good-Timers,” she says.

Behind the truck, Thumpertown Beach looks like a painting: shimmering blue and white, wide-brimmed hats and board shorts, umbrellas and buckets, gleeful children everywhere. A minute after Waite parks, customers form a line.

Julian Gunnison, 8, from Raynham, has been a regular his whole life. The back of his T-shirt reads “I Found Good Times on Cape Cod.” Waite takes his order, then invites him into the truck for a look around.

“He’s a kid with a heart of gold,” says Waite. Last year, on his last day vacationing in Eastham, he delivered her a handwritten card. “He’s the sweetest of the sweets,” she says.