Separated both component

component/noVNC/buildout.cfg

 [buildout]
-
 parts =
   noVNC
   websockify
@@ -9,9 +8,3 @@ recipe = hexagonit.recipe.download
 url = https://github.com/kanaka/noVNC/tarball/master
 strip-top-level-dir = true
 
-[websockify]
-noVNC_dummy = ${noVNC:location}
-recipe = hexagonit.recipe.download
-url = https://github.com/desaintmartin/websockify/tarball/master
-strip-top-level-dir = true
-destination = ${noVNC:location}/utils/

component/websockify/buildout.cfg

+[buildout]
+extends =
+ ../noVNC/buildout.cfg
+
+parts =
+  websockify
+
+[websockify]
+recipe = hexagonit.recipe.download
+url = https://github.com/desaintmartin/websockify/tarball/master
+strip-top-level-dir = true
+destination = ${noVNC:location}/utils/
\ No newline at end of file