diff --git a/x/backend.go b/x/backend.go
index 3fc3cc5..a73f79d 100644
--- a/x/backend.go
+++ b/x/backend.go
@@ -126,7 +126,7 @@ func (this *Backend) NewTexture (source image.Image) canvas.TextureCloser {
 	return xcanvas.NewTextureFrom(source)
 }
 
-func (this *Backend) NewCanvas (bounds image.Rectangle) canvas.Canvas {
+func (this *Backend) NewCanvas (bounds image.Rectangle) canvas.CanvasCloser {
 	return xcanvas.NewCanvas(this.x, bounds)
 }
 
diff --git a/x/canvas/canvas.go b/x/canvas/canvas.go
index 748bfe5..8b6a72a 100644
--- a/x/canvas/canvas.go
+++ b/x/canvas/canvas.go
@@ -49,9 +49,10 @@ func (this *Canvas) Push (window xproto.Window) {
 }
 
 // Close frees this canvas from the X server.
-func (this *Canvas) Close () {
+func (this *Canvas) Close () error {
 	this.assert()
 	this.Image.Destroy()
+	return nil
 }
 
 func (this *Canvas) assert () {