diff --git a/piker/ui/_curve.py b/piker/ui/_curve.py
index ad415031..cb696257 100644
--- a/piker/ui/_curve.py
+++ b/piker/ui/_curve.py
@@ -133,7 +133,7 @@ class Curve(pg.GraphicsObject):
         # self.last_step_pen = pg.mkPen(hcolor(color), width=2)
         self.last_step_pen = pg.mkPen(pen, width=2)
 
-        self._last_line = QLineF()
+        self._last_line: QLineF = QLineF()
 
         # flat-top style histogram-like discrete curve
         # self._step_mode: bool = step_mode
@@ -182,6 +182,13 @@ class Curve(pg.GraphicsObject):
         else:
             return 0
 
+    def x_last(self) -> float:
+        '''
+        Return the last most x value of the last line segment.
+
+        '''
+        return self._last_line.x2()
+
     def px_width(self) -> float:
 
         vb = self.getViewBox()
diff --git a/piker/ui/_ohlc.py b/piker/ui/_ohlc.py
index 9a37bbfa..a7e36146 100644
--- a/piker/ui/_ohlc.py
+++ b/piker/ui/_ohlc.py
@@ -114,12 +114,20 @@ class BarItems(pg.GraphicsObject):
 
         self.setCacheMode(QtWidgets.QGraphicsItem.DeviceCoordinateCache)
         self.path = QPainterPath()
-        self._last_bar_lines: Optional[tuple[QLineF, ...]] = None
+
+        self._last_bar_lines: tuple[QLineF, ...] | None = None
 
     def x_uppx(self) -> int:
         # we expect the downsample curve report this.
         return 0
 
+    def x_last(self) -> float:
+        '''
+        Return the last most x value of the close line segment.
+
+        '''
+        return self._last_bar_lines[-1].x2()
+
     # Qt docs: https://doc.qt.io/qt-5/qgraphicsitem.html#boundingRect
     def boundingRect(self):
         # profiler = Profiler(