diff --git a/fasta.cabal b/fasta.cabal
--- a/fasta.cabal
+++ b/fasta.cabal
@@ -10,7 +10,7 @@
 -- PVP summary:      +-+------- breaking API changes
 --                   | | +----- non-breaking API additions
 --                   | | | +--- code changes with no API change
-version:             0.5.1.3
+version:             0.5.1.5
 
 -- A short (one-line) description of the package.
 synopsis:            A simple, mindless parser for fasta files.
@@ -64,7 +64,7 @@
   -- other-modules:       
   
   -- Other library packages from which modules are imported.
-  build-depends:       base >=4.6 && <4.8,
+  build-depends:       base >=4.6 && <4.9,
                        parsec >=3.1.0 && <4.0,
                        text >=1.1.0 && <1.4,
                        containers >= 0.5 && <0.6,
diff --git a/src/Data/Fasta/Text/Lazy/Parse.hs b/src/Data/Fasta/Text/Lazy/Parse.hs
--- a/src/Data/Fasta/Text/Lazy/Parse.hs
+++ b/src/Data/Fasta/Text/Lazy/Parse.hs
@@ -41,7 +41,7 @@
                                      . map toUpper
                                      . removeWhitespace $ fseq } )
   where
-    removeWhitespace = filter (`notElem` "\n\r ")
+    removeWhitespace = filter (`notElem` ("\n\r " :: String))
 
 fastaFile :: Parsec T.Text u [FastaSequence]
 fastaFile = do
diff --git a/src/Data/Fasta/Text/Parse.hs b/src/Data/Fasta/Text/Parse.hs
--- a/src/Data/Fasta/Text/Parse.hs
+++ b/src/Data/Fasta/Text/Parse.hs
@@ -42,7 +42,7 @@
                                      . removeWhitespace
                                      $ fseq } )
   where
-    removeWhitespace = filter (`notElem` "\n\r ")
+    removeWhitespace = filter (`notElem` ("\n\r " :: String))
 
 fastaFile :: Parsec T.Text u [FastaSequence]
 fastaFile = do