edge to cache test variations 8. In VCL_RECV, add a second bucket assignment: set var.testKey = req.http.ab "buttonSize"; set var.userTestSlot = fastly.hash(var.testKey, 0, 1, 100); set req.http.ab-buttonSize = if (var.userTestSlot <= 20, "small", if (var.userTestSlot <= 30, "medium", "large" ));