This is Phlox pungens. Picture taken today.
It is not a particularly pleasant thing to weed around, or even to touch. Not a cushion phlox. More of a wanderer. Flowers white.
"Perennial forming loose mats, 5cm or less high .....leaves very stiff and pungent, mostly lanceolate or lance-linear. 4-8mm long, 1-1.5 (2mm) wide, pubescent. often glandular, ciliate, punctate, the margins and dorsal midrib strongly thickened, gradually tapering into a sharp terminal bristle..."). (From Dorn's Vascular Plants of Wyoming, 1988.)