Finely grate zest from limes. Cut limes crosswise in half; squeeze juice from limes. Transfer zest and juice to a small saucepan. Stir in remaining ingredients. Bring to a boil, stirring to dissolve sugar. Reduce heat to medium; cook, uncovered, until berries pop, 12-15 minutes, stirring occasionally. Remove from heat.
Transfer to a small bowl; refrigerate, covered, until cold.
