diff --git a/Unique.cabal b/Unique.cabal
--- a/Unique.cabal
+++ b/Unique.cabal
@@ -1,6 +1,6 @@
 name:                Unique
 
-version:             0.4.6
+version:             0.4.6.1
 
 synopsis:            It provides the functionality like unix "uniq" utility
 description:         Library provides the functions to find unique and duplicate elements in the list
@@ -21,7 +21,7 @@
                         Data.List.UniqueStrict,
                         Data.List.UniqueUnsorted
 
-  build-depends:         base >=4.0 && < 5
+  build-depends:         base >=4.0 && < 4.10
                        , extra
                        , containers
                        , hashable
@@ -39,7 +39,7 @@
                      , RepeatedBy
                      , SortUniq
 
-  build-depends:       base >=4.8 && <4.9
+  build-depends:       base >=4.0 && < 4.10
                      , hspec
                      , containers
                      , QuickCheck
diff --git a/tests/IsUnique.hs b/tests/IsUnique.hs
--- a/tests/IsUnique.hs
+++ b/tests/IsUnique.hs
@@ -47,16 +47,14 @@
 
   it "isUnique should return (Just ANY) when element is exist in the list" $
     property $
-    \ ( NonEmpty ls@(x:xs) )
-    -> not (null xs)
-       ==>  isJust (isUnique (x :: Char) ls)
+    \ ( NonEmpty ls@(x:_) )
+    -> isJust (isUnique (x :: Char) ls)
 
   context "isUnique should return (Just False) when at least two elements are exist in the list" $
     it "- It checks laziness as well" $
       property $
-        \ ( NonEmpty ls@(x:xs) )
-        -> not (null xs)
-           ==>  isJust $ isUnique (x :: Char) (ls ++ [x, undefined])
+      \ ( NonEmpty ls@(x:_) )
+      ->  isJust $ isUnique (x :: Char) (ls ++ [x, undefined])
 
   it "isUnique should return Nothing when element is absent in the list" $
     property $
@@ -70,5 +68,3 @@
     -> notElem x xs
        ==> isNothing (isUnique (x :: Char) xs)
        &&  isNothing (isRepeated x xs)
-
-
diff --git a/tests/RepeatedBy.hs b/tests/RepeatedBy.hs
--- a/tests/RepeatedBy.hs
+++ b/tests/RepeatedBy.hs
@@ -51,6 +51,10 @@
     property $
     \ xs -> unique (xs :: String) == unique (unique xs)
 
+  it "repeated: multiple execution should return []" $
+    property $
+    \ xs -> null (repeated (repeated (xs :: String) ))
+
   it "repeated && unique: should return different result on the same non empty list" $
     property $
     \ xs -> not (null xs)