diff --git a/indexation.cabal b/indexation.cabal
--- a/indexation.cabal
+++ b/indexation.cabal
@@ -1,5 +1,5 @@
 name: indexation
-version: 0.6.3
+version: 0.6.4
 category: Data
 synopsis: Tools for entity indexation
 description: A set of tools for indexing entities
@@ -49,8 +49,8 @@
     hashable >=1 && <2,
     list-t >=1 && <1.1,
     mmorph >=1 && <2,
-    potoki >=2.1 && <2.2,
-    potoki-cereal >=0.3 && <0.4,
+    potoki >=2.1.3 && <2.2,
+    potoki-cereal >=0.3.1 && <0.4,
     profunctors >=5.2 && <6,
     stm-containers >=1.1 && <1.2,
     text >=1 && <2,
diff --git a/library/Indexation/IO.hs b/library/Indexation/IO.hs
--- a/library/Indexation/IO.hs
+++ b/library/Indexation/IO.hs
@@ -17,6 +17,7 @@
 import Indexation.Types
 import Indexation.Instances ()
 import qualified Potoki.IO as PotokiIo
+import qualified Potoki.Cereal.IO as PotokiIo
 import qualified Potoki.Produce as PotokiProduce
 import qualified Potoki.Consume as PotokiConsume
 import qualified Potoki.Cereal.Consume as PotokiConsume
@@ -68,13 +69,7 @@
       Left x -> error ("Unexpected binary parsing error: " <> x)
 
 readEntityTableFromFile :: Serialize entity => FilePath -> IO (Either IOException (Either Text (EntityTable entity)))
-readEntityTableFromFile filePath =
-  PotokiIo.produceAndConsume
-    (PotokiProduce.fileBytes filePath)
-    (right' (PotokiConsume.get Cereal.get))
+readEntityTableFromFile = PotokiIo.deserializeFromFile
 
 readIndexTableFromFile :: (Serialize entity, Eq entity, Hashable entity) => FilePath -> IO (Either IOException (Either Text (IndexTable entity)))
-readIndexTableFromFile filePath =
-  PotokiIo.produceAndConsume
-    (PotokiProduce.fileBytes filePath)
-    (right' (PotokiConsume.get Cereal.get))
+readIndexTableFromFile = PotokiIo.deserializeFromFile
diff --git a/library/Indexation/Potoki/Produce.hs b/library/Indexation/Potoki/Produce.hs
--- a/library/Indexation/Potoki/Produce.hs
+++ b/library/Indexation/Potoki/Produce.hs
@@ -3,6 +3,7 @@
   entities,
   counts,
   indexedCounts,
+  indices,
 )
 where
 
@@ -10,6 +11,7 @@
 import Indexation.Types
 import qualified Potoki.Produce as Produce
 import qualified Data.Vector.Generic as GenericVector
+import qualified DenseIntSet
 
 
 entities :: EntityTable a -> Produce a
@@ -26,3 +28,9 @@
 -}
 indexedCounts :: IndexCounts a -> Produce (Int, Word32)
 indexedCounts (IndexCounts vector) = Produce.vectorWithIndices vector
+
+{-|
+Indices, which are present in the set.
+-}
+indices :: IndexSet a -> Produce (Index a)
+indices (IndexSet set) = coerce (Produce.unfoldr (DenseIntSet.presentElementsUnfoldr set))