BalletX’s dancers will bring “The Last Glass” to Union Market this weekend. (Erin Baiano)

If you go shopping at Union Market this weekend, you may see dancers sashaying through the parking lot or twirling on a neighboring roof. Before you join in and start dancing through the aisles yourself, consider leaving things to the professionals.

“We have portable dance floors and we’re up for anything,” says Christine Cox, co-founder and artistic/executive director of Philadelphia’s BalletX, the experimental ballet company behind this weekend’s performances at the marketplace. “We’re up for any unique challenge to show the world what ballet can be.”

Founded in 2005, BalletX was “created as an experiment to play and have fun,” says Cox, who was a company member with the Pennsylvania Ballet at the time. “Now we focus on world-premiere choreography. We’re like an incubator/lab for choreographers to create new works that stem from ballet technique and go into world dance.”

Choreographed by BalletX co-founder Matthew Neenan to the music of indie band Beirut, the frolic through the market Sunday afternoon will feature all 10 of the company’s dancers and launch the new Halcyon Stage Pop-Up @ Union Market series, which brings free dance, classical music and opera performances to the public market.

BalletX has never performed in a public market before (Halcyon Stage artistic director Septime Webre came up with the idea), but as a company of dancers and choreographers trained in classical ballet seeking to “create a new language of dance,” they’re up to the task, Cox says.

“The dancers are very used to working together. They’re daring and courageous, and they’ll be in sneakers, not pointe shoes,” Cox says. “They’ll be more like moving sculptures in 5-by-5-foot areas throughout the market, with boomboxes in each area playing Beirut.”

If you’re the kind of person who’d rather sit down to watch dancers instead of chasing them around a busy market, there will also be a more traditional performance Saturday night at Dock 5, the market’s warehouse event space. The program will include the full Neenan-Beirut piece, “The Last Glass,” which Cox describes as “a kaleidoscope of stories.” (The piece was shortened and reworked for Sunday’s pop-up performance.) A second piece to be performed at Dock 5, “Big Ones,” is choreographer Trey McIntyre’s take on the life story of Amy Winehouse, featuring the late singer’s music.

Wherever they perform, the members of BalletX are always eager to take on something new. “We dance because we love it,” Cox says, “and when a performer truly wants to connect, the community welcomes them with open arms.”

Union Market, 1309 Fifth St. NE; Sat., 8 p.m., $40; Sun., noon–2 p.m., free.