diff --git a/lib/plot.py b/lib/plot.py
index 72c0129..5ee70c5 100644
--- a/lib/plot.py
+++ b/lib/plot.py
@@ -178,6 +178,7 @@ class SVGPlotter(Plotter):
         self.context = cairo.Context(self.surface)
         self.context.scale(dpi / 25.4, dpi / 25.4)
         self.context.set_line_cap(cairo.LINE_CAP_ROUND)
+        self.context.set_line_join(cairo.LINE_JOIN_ROUND)
 
         super().__init__(paper, line_width, colour)