diff --git a/hyraxAbif.cabal b/hyraxAbif.cabal
--- a/hyraxAbif.cabal
+++ b/hyraxAbif.cabal
@@ -1,6 +1,6 @@
 cabal-version:       2.2
 name:                hyraxAbif
-version:             0.2.4.4
+version:             0.2.4.5
 synopsis:            Modules for parsing, generating and manipulating AB1 files.
 homepage:            https://github.com/hyraxbio/hyraxAbif/#readme
 license:             BSD-3-Clause OR Apache-2.0
@@ -17,7 +17,7 @@
                      <<data:image/png;base64,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>>
                      .
                      Any AB1 file conforming to the standard at <http://www6.appliedbiosystems.com/support/software_community/ABIF_File_Format.pdf> should be supported.
-                     .   
+                     .
                      This library also support generating a minimal ABIF file from a FASTA input sequence.
                      .
                      A basic terminal application that can dump and generate AB1s is included. See <https://github.com/hyraxbio/hyraxAbif/blob/master/app/Main.hs>
@@ -44,13 +44,13 @@
                      , Examples.ReadAb1
   build-depends:       base            >= 4.9.1.0 && < 5
                      , verset          >= 0.0.1.8 && < 0.0.2.0
-                     , binary          >= 0.8.9 && < 0.9
-                     , bytestring      >= 0.11.3 && < 0.12
+                     , binary          >= 0.8.9 && < 0.10
+                     , bytestring      >= 0.11.3 && < 0.13
                      , directory       >= 1.3.6 && < 1.4
-                     , filepath        >= 1.4.2 && < 1.5
-                     , hscolour        >= 1.24.4 && < 1.25
+                     , filepath        >= 1.4.2 && < 1.6
+                     , hscolour        >= 1.24.4 && < 1.26
                      , pretty-show     >= 1.10 && < 1.11
-                     , text            >= 1.2.5 && < 2.1
+                     , text            >= 1.2.5 && < 2.2
   default-language:    Haskell2010
 
 
@@ -61,10 +61,10 @@
   build-depends:       base            >= 4.9.1.0 && < 5
                      , hyraxAbif
                      , verset          >= 0.0.1.8 && < 0.0.2.0
-                     , text            >= 1.2.5 && < 2.1
-                     , bytestring      >= 0.11.3 && < 0.12
+                     , text            >= 1.2.5 && < 2.2
+                     , bytestring      >= 0.11.3 && < 0.13
                      , pretty-show     >= 1.10 && < 1.11
-                     , hscolour        >= 1.24.4 && < 1.25
+                     , hscolour        >= 1.24.4 && < 1.26
   default-language:    Haskell2010
 
 test-suite hyraxAbif-test
@@ -74,10 +74,10 @@
   build-depends:       base            >= 4.9.1.0  && < 5
                      , hyraxAbif
                      , verset          >= 0.0.1.8 && < 0.0.2.0
-                     , text            >= 1.2.5 && < 2.1
-                     , bytestring      >= 0.11.3 && < 0.12
-                     , binary          >= 0.8.9 && < 0.9
-                     , hedgehog
+                     , text            >= 1.2.5 && < 2.2
+                     , bytestring      >= 0.11.3 && < 0.13
+                     , binary          >= 0.8.9 && < 0.10
+                     , hedgehog        >= 1.2 && < 1.5
   other-modules:       AbifTests
                      , FastaTests
                      , Generators
diff --git a/test/AbifTests.hs b/test/AbifTests.hs
--- a/test/AbifTests.hs
+++ b/test/AbifTests.hs
@@ -32,10 +32,10 @@
 
   nucs === n2
 
-  
+
 -- | Test that an ab1 (write, read, write, read) results in the original data
 prop_roundtrip :: Property
-prop_roundtrip = property $ do 
+prop_roundtrip = property $ do
   fdata <- forAll $ genFastaData 2
   let fasta = TxtE.encodeUtf8 $ toFastaTxt False fdata
 
@@ -47,8 +47,8 @@
   ab1Read2 <- evalEither $ H.getAbif ab1Written2
 
   ab1Read1 === ab1Read2
-  
-  
+
+
 -- | Generate an ab1 from a fasta and then confirm that the generated peaks of the
 --    chromatogram match the original fasta.
 --    Note that we are only testing the simple/single fasta case (i.e. no mixes)
@@ -93,15 +93,17 @@
       case reverse $ Lst.sortOn snd [('A', a), ('C', c), ('G', g), ('T', t)] of
         ((n,_) : _) -> n
         _ -> '?'
-    
+
     readDataPeaks :: H.Abif -> Int -> [Int] -> Either Text [Int]
     readDataPeaks ab1 dirNum peaks =
       case readShorts <$> getDirEntry ab1 "DATA" dirNum of
         Left e -> Left e
         Right vs ->
           let valsAtPeaks = atMay vs <$> peaks in
-          maybeToRight "peaks" $ sequenceA valsAtPeaks
-  
+          case sequenceA valsAtPeaks of
+            Nothing -> Left "Could not read peaks"
+            Just vs' -> Right vs'
+
 
 getDirEntry :: H.Abif -> Text -> Int -> Either Text BSL.ByteString
 getDirEntry ab1 dirName dirNum =
diff --git a/test/Generators.hs b/test/Generators.hs
--- a/test/Generators.hs
+++ b/test/Generators.hs
@@ -13,21 +13,21 @@
 
 -- | Generate random set of nucleotides, including ambiguous ones
 nucsGen :: GenT Identity Text
-nucsGen = 
-  Gen.text (Range.linear 1 1000) (Gen.element "ACGTMRWSYKVHDBNX")
+nucsGen =
+  Gen.text (Range.linear 1 1000) (Gen.element ("ACGTMRWSYKVHDBNX" :: [Char]))
 
 
 -- | Generate random set of nucleotides, no ambiguous ones
 nucsNoIupacGen :: (Monad m) => PropertyT m Text
-nucsNoIupacGen = 
-  forAll $ Gen.text (Range.linear 1 1000) (Gen.element "ACGT")
+nucsNoIupacGen =
+  forAll $ Gen.text (Range.linear 1 1000) (Gen.element ("ACGT" :: [Char]))
 
-  
+
 -- | Generate data to construct a fasta "file"
 --   List of tuples of (name, lines of reads)
 --      maxReads controls the max number in the list
 genFastaData :: Int -> Gen [(Int, [Text])]
-genFastaData maxReads = 
+genFastaData maxReads =
   Gen.list (Range.linear 1 maxReads) $
     (,) <$> Gen.int (Range.linear 1 9999) <*> Gen.list (Range.linear 1 15) nucsGen
 
@@ -36,7 +36,7 @@
 toFastaTxt :: Bool -> [(Int, [Text])] -> Text
 toFastaTxt addSpaces is =
   Txt.intercalate "\n" $ toRead <$> is
-  
+
   where
     toRead (weight, ls) =
       let sp = if addSpaces then "  " else "" in
@@ -47,7 +47,7 @@
 toFasta :: [(Int, [Text])] -> [F.Fasta]
 toFasta is =
   toRead <$> is
-  
+
   where
     toRead (weight, ls) = F.Fasta (show weight) $ Txt.concat ls
 
diff --git a/test/Tests.hs b/test/Tests.hs
--- a/test/Tests.hs
+++ b/test/Tests.hs
@@ -2,6 +2,7 @@
 
 import           Verset
 import qualified System.IO as IO
+import           System.Exit (exitFailure)
 
 import qualified AbifTests
 import qualified FastaTests
@@ -11,9 +12,9 @@
   IO.hSetBuffering IO.stdout IO.LineBuffering
   IO.hSetBuffering IO.stderr IO.LineBuffering
 
-  results <- sequence [ AbifTests.tests
-                      , FastaTests.tests
-                      ]
+  results <- sequenceA [ AbifTests.tests
+                       , FastaTests.tests
+                       ]
 
   if and results
     then pass
