diff --git a/redo-ifchange.py b/redo-ifchange.py
index 62203b8..2d4b207 100755
--- a/redo-ifchange.py
+++ b/redo-ifchange.py
@@ -4,7 +4,7 @@ import vars, state, builder
 from helpers import debug, err, mkdirp, unlink
 
 
-def _dirty_deps(t, depth):
+def dirty_deps(t, depth):
     debug('%s?%s\n' % (depth, t))
     if state.isbuilt(t):
         debug('%s-- DIRTY (built)\n' % depth)
@@ -35,18 +35,12 @@ def _dirty_deps(t, depth):
         elif mode == 'm':
             if dirty_deps(os.path.join(vars.BASE, name), depth + '  '):
                 debug('%s-- DIRTY (sub)\n' % depth)
+                state.unstamp(t)  # optimization for future callers
                 return True
     state.mark(t)
     return False
 
 
-def dirty_deps(t, depth):
-    if _dirty_deps(t, depth):
-        state.unstamp(t)
-        return True
-    return False
-
-
 def should_build(t):
     return not state.isbuilt(t) and dirty_deps(t, depth = '')