diff --git a/default.nix b/default.nix
index 545f676..314ae3b 100644
--- a/default.nix
+++ b/default.nix
@@ -9,5 +9,4 @@ bcd-lts.mkBiocadProject {
   shellArgs = {
     buildInputs = [ bcd-lts.pkgs.RNA ];
   };
-  compiler = "ghc925";
 }
diff --git a/src/Bio/FASTA/Type.hs b/src/Bio/FASTA/Type.hs
index f599e5c..262d70c 100644
--- a/src/Bio/FASTA/Type.hs
+++ b/src/Bio/FASTA/Type.hs
@@ -27,7 +27,7 @@ data FastaItem a
       , sequ :: BareSequence a
         -- ^ bare sequence
       }
-  deriving (Eq, Show, Functor)
+  deriving (Eq, Ord, Show, Functor)
 
 class ParsableFastaToken a where
     parseToken :: (Char -> Bool) -> Parsec Void Text a
diff --git a/src/Bio/Sequence/Class.hs b/src/Bio/Sequence/Class.hs
index 8503fe3..14b4297 100644
--- a/src/Bio/Sequence/Class.hs
+++ b/src/Bio/Sequence/Class.hs
@@ -73,7 +73,7 @@ data Sequence mk w a
       , _weights  :: Vector w
         -- ^ weights for all elements in sequence
       }
-  deriving (Eq, Show, Generic, NFData, Functor)
+  deriving (Eq, Ord, Show, Generic, NFData, Functor)
 
 instance Semigroup (Sequence mk w a) where
   sequA <> sequB = res
diff --git a/src/Bio/Sequence/Range.hs b/src/Bio/Sequence/Range.hs
index 6e14f56..26545c5 100644
--- a/src/Bio/Sequence/Range.hs
+++ b/src/Bio/Sequence/Range.hs
@@ -35,7 +35,7 @@ import GHC.Generics    (Generic)
 data Border
   = Precise
   | Exceeded
-  deriving (Eq, Show, Generic, NFData)
+  deriving (Eq, Ord, Show, Generic, NFData)
 
 -- | The end point of a range with indication whether it is @Precise@ of @Exceeded@ (see @Border@).
 --
@@ -44,7 +44,7 @@ data RangeBorder
       { _borderType     :: Border
       , _borderLocation :: Int
       }
-  deriving (Eq, Show, Generic, NFData)
+  deriving (Eq, Ord, Show, Generic, NFData)
 
 makeLenses ''RangeBorder
 
@@ -80,7 +80,7 @@ data Range
       }
   -- ^ Indicates that the range is complementary.
   -- Example in GB:  rep             complement(69..420)
-  deriving (Eq, Show, Generic, NFData)
+  deriving (Eq, Ord, Show, Generic, NFData)
 
 makeLenses ''Range