Heat the oven to 400ºF.
Remove the casing from the merguez and discard. Crumble the sausage into a pan set over medium high heat. Sauté until just cooked through, 4-5 minutes. Drain.
Arrange the flatbreads on a baking sheet. Spread each flatbread with 2 tablespoons hummus; season with za'atar. Top with cooked merguez and feta.
Bake 13-15 minutes, or until the flatbreads are crisp and golden brown around the edges. Remove from the oven and top with mint.