diff --git a/src/cairo-beos-surface.cpp b/src/cairo-beos-surface.cpp
index b6448fa69..c952e018b 100644
--- a/src/cairo-beos-surface.cpp
+++ b/src/cairo-beos-surface.cpp
@@ -777,6 +777,7 @@ _cairo_beos_surface_get_extents (void              *abstract_surface,
 }
 
 static const struct _cairo_surface_backend cairo_beos_surface_backend = {
+    CAIRO_SURFACE_TYPE_BEOS,
     NULL, /* create_similar */
     _cairo_beos_surface_finish,
     _cairo_beos_surface_acquire_source_image,