--- a/commitwatcher/store.py	Thu Sep 26 22:27:11 2013 -0700
+++ b/commitwatcher/store.py	Fri Sep 27 11:17:27 2013 -0700
@@ -1,15 +1,27 @@
 from abc import abstractmethod
 
 class CommitStore(object):
-    """ABC for commits"""
+    """
+    ABC for commits
+    """
 
     @abstractmethod
     def add(self, commit):
         """adds a commit to the store"""
 
+    @abstractmethod
+    def paths(self, *commits):
+        """return all paths touched for a given commit"""
+
+
 class MemoryStore(CommitStore):
     """store in volatile memory"""
     # volatile!
 
     def add(self, commit):
-        raise NotImplementedError
+        raise NotImplementedError()
+
+    def paths(self, *commits):
+        """
+        return touched by commits
+        """