diff --git a/src/xrt/auxiliary/util/u_var.h b/src/xrt/auxiliary/util/u_var.h
index 55288dd42..0cd2417ce 100644
--- a/src/xrt/auxiliary/util/u_var.h
+++ b/src/xrt/auxiliary/util/u_var.h
@@ -162,6 +162,7 @@ enum u_var_kind
 	U_VAR_KIND_U16,
 	U_VAR_KIND_U64,
 	U_VAR_KIND_I32,
+	U_VAR_KIND_I64,
 	U_VAR_KIND_F32,
 	U_VAR_KIND_DRAGGABLE_F32,
 	U_VAR_KIND_F64,
@@ -273,6 +274,7 @@ u_var_force_on(void);
 	ADD_FUNC(u16, uint16_t, U16)                                                                                   \
 	ADD_FUNC(u64, uint64_t, U64)                                                                                   \
 	ADD_FUNC(i32, int32_t, I32)                                                                                    \
+	ADD_FUNC(i64, int64_t, I64)                                                                                    \
 	ADD_FUNC(f32, float, F32)                                                                                      \
 	ADD_FUNC(f64, double, F64)                                                                                     \
 	ADD_FUNC(f32_arr, struct u_var_f32_arr, F32_ARR)                                                               \
diff --git a/src/xrt/state_trackers/gui/gui_scene_debug.c b/src/xrt/state_trackers/gui/gui_scene_debug.c
index 7231c4135..7c0adaa8d 100644
--- a/src/xrt/state_trackers/gui/gui_scene_debug.c
+++ b/src/xrt/state_trackers/gui/gui_scene_debug.c
@@ -359,6 +359,7 @@ on_elem(struct u_var_info *info, void *priv)
 	case U_VAR_KIND_U16: igDragScalar(name, ImGuiDataType_U16, ptr, drag_speed, NULL, NULL, NULL, power); break;
 	case U_VAR_KIND_U64: igDragScalar(name, ImGuiDataType_U64, ptr, drag_speed, NULL, NULL, NULL, power); break;
 	case U_VAR_KIND_I32: igInputInt(name, (int *)ptr, 1, 10, i_flags); break;
+	case U_VAR_KIND_I64: igInputScalar(name, ImGuiDataType_S64, ptr, NULL, NULL, NULL, i_flags); break;
 	case U_VAR_KIND_VEC3_I32: igInputInt3(name, (int *)ptr, i_flags); break;
 	case U_VAR_KIND_F32: igInputFloat(name, (float *)ptr, 1, 10, "%+f", i_flags); break;
 	case U_VAR_KIND_F64: igInputDouble(name, (double *)ptr, 0.1, 1, "%+f", i_flags); break;