diff --git a/ext/GalerkinToolkitWriteVTKExt.jl b/ext/GalerkinToolkitWriteVTKExt.jl
index 823610b6..5445b5c6 100644
--- a/ext/GalerkinToolkitWriteVTKExt.jl
+++ b/ext/GalerkinToolkitWriteVTKExt.jl
@@ -1,7 +1,7 @@
 module GalerkinToolkitWriteVTKExt
 
 using GalerkinToolkit
-import GalerkinToolkit: plot, plot!, translate_vtk_data, translate_vtk_data!
+import GalerkinToolkit: plot, plot!, translate_vtk_data, translate_vtk_data!, vtk_close_impl, vtk_close_impl!
 import GalerkinToolkit: vtk_points, vtk_points!, vtk_cells, vtk_cells!, vtk_args, vtk_args!
 import GalerkinToolkit: vtk_physical_faces, vtk_physical_faces!, vtk_physical_nodes, vtk_physical_nodes!
 import GalerkinToolkit: vtk_mesh_cell, vtk_mesh_cell!
diff --git a/src/visualization.jl b/src/visualization.jl
index a11649de..e38c8121 100644
--- a/src/visualization.jl
+++ b/src/visualization.jl
@@ -432,6 +432,8 @@ end
 
 function translate_vtk_data end
 function translate_vtk_data! end
+function vtk_close_impl end
+function vtk_close_impl! end
 
 # Makie prototype functions to be defined inside Makie's extension module; see ext/GalerkinToolkitMakieExt.jl