diff --git a/src/Data/RandomWalkSimilarity.hs b/src/Data/RandomWalkSimilarity.hs
index f386237bb..0e39d53e6 100644
--- a/src/Data/RandomWalkSimilarity.hs
+++ b/src/Data/RandomWalkSimilarity.hs
@@ -32,7 +32,7 @@ rws compare getLabel as bs
         fbs = featurize bs
         kdas = KdTree.build (Vector.toList . fst . fst) fas
         featurize a = zip ((featureVector d . pqGrams p q getLabel &&& identity) <$> a) ([0..] :: [Integer])
-        findNearestNeighbourTo kv@((_, v), i) = do
+        findNearestNeighbourTo kv@((_, v), _) = do
           mapped <- get
           let ((k, nearest), j) = KdTree.nearest kdas kv
           if k `Set.member` mapped