diff --git a/hedgehog-extras.cabal b/hedgehog-extras.cabal
--- a/hedgehog-extras.cabal
+++ b/hedgehog-extras.cabal
@@ -1,7 +1,7 @@
 cabal-version: 2.4
 
 name:                   hedgehog-extras
-version:                0.6.0.2
+version:                0.6.1.0
 synopsis:               Supplemental library for hedgehog
 description:            Supplemental library for hedgehog.
 category:               Test
@@ -16,7 +16,7 @@
   type:                 git
   location:             https://github.com/input-output-hk/hedgehog-extras
 
-common aeson                        { build-depends: aeson                            >= 2.1.0.0                  }
+common aeson                        { build-depends: aeson                            >= 2.0.0.0                  }
 common aeson-pretty                 { build-depends: aeson-pretty                     >= 0.8.5                    }
 common async                        { build-depends: async                                                        }
 common base                         { build-depends: base                             >= 4.12       && < 4.20     }
diff --git a/src/Hedgehog/Extras/Test/File.hs b/src/Hedgehog/Extras/Test/File.hs
--- a/src/Hedgehog/Extras/Test/File.hs
+++ b/src/Hedgehog/Extras/Test/File.hs
@@ -1,5 +1,6 @@
 {-# LANGUAGE BangPatterns #-}
 {-# LANGUAGE TypeApplications #-}
+{-# LANGUAGE RankNTypes #-}
 
 module Hedgehog.Extras.Test.File
   ( createDirectoryIfMissing
@@ -193,60 +194,61 @@
   void . H.annotate $ "Reading file: " <> filePath
   H.evalIO $ T.readFile filePath
 
--- | Read the 'filePath' file as JSON.
-readJsonFile :: (MonadTest m, MonadIO m, HasCallStack) => FilePath -> m (Either String Value)
+-- | Read the 'filePath' file as JSON. Use @readJsonFile \@'Value'@ to decode into 'Value'.
+readJsonFile :: forall a m. (MonadTest m, MonadIO m, Y.FromJSON a, HasCallStack) => FilePath -> m (Either String a)
 readJsonFile filePath = GHC.withFrozenCallStack $ do
   void . H.annotate $ "Reading JSON file: " <> filePath
-  H.evalIO $ J.eitherDecode @Value <$> LBS.readFile filePath
+  H.evalIO $ J.eitherDecode <$> LBS.readFile filePath
 
--- | Read the 'filePath' file as JSON. Same as 'readJsonFile' but fails on error.
-readJsonFileOk :: (MonadTest m, MonadIO m, HasCallStack) => FilePath -> m Value
+-- | Read the 'filePath' file as JSON. Same as 'readJsonFile' but fails on error.  Use
+-- @readJsonFileOk \@'Value'@ to decode into 'Value'.
+readJsonFileOk :: forall a m.(MonadTest m, MonadIO m, Y.FromJSON a, HasCallStack) => FilePath -> m a
 readJsonFileOk filePath = GHC.withFrozenCallStack $
   H.leftFailM $ readJsonFile filePath
 
-rewriteLbsJson :: (MonadTest m, HasCallStack) => (Value -> Value) -> LBS.ByteString -> m LBS.ByteString
+rewriteLbsJson :: forall a m. (MonadTest m, Y.FromJSON a, Y.ToJSON a, HasCallStack) => (a -> a) -> LBS.ByteString -> m LBS.ByteString
 rewriteLbsJson f lbs = GHC.withFrozenCallStack $ do
   case J.eitherDecode lbs of
     Right iv -> return (J.encode (f iv))
     Left msg -> H.failMessage GHC.callStack msg
 
 -- | Rewrite the 'filePath' JSON file using the function 'f'.
-rewriteJsonFile :: (MonadTest m, MonadIO m, HasCallStack) => FilePath -> (Value -> Value) -> m ()
+rewriteJsonFile :: forall a m. (MonadTest m, MonadIO m, Y.FromJSON a, Y.ToJSON a, HasCallStack) => FilePath -> (a -> a) -> m ()
 rewriteJsonFile filePath f = GHC.withFrozenCallStack $ do
   void . H.annotate $ "Rewriting JSON file: " <> filePath
   lbsReadFile filePath >>= rewriteLbsJson f >>= lbsWriteFile filePath
 
 -- | Rewrite the 'filePath' JSON file using the function 'f'.
-copyRewriteJsonFile :: (MonadTest m, MonadIO m, HasCallStack) => FilePath -> FilePath -> (Value -> Value) -> m ()
+copyRewriteJsonFile :: forall a m. (MonadTest m, MonadIO m, Y.FromJSON a, Y.ToJSON a, HasCallStack) => FilePath -> FilePath -> (a -> a) -> m ()
 copyRewriteJsonFile src dst f = GHC.withFrozenCallStack $ do
   void . H.annotate $ "Rewriting JSON from file: " <> src <> " to file " <> dst
   lbsReadFile src >>= rewriteLbsJson f >>= lbsWriteFile dst
 
 -- | Read the 'filePath' file as YAML.
-readYamlFile :: (MonadTest m, MonadIO m, HasCallStack) => FilePath -> m (Either Y.ParseException Value)
+readYamlFile :: forall a m. (MonadTest m, MonadIO m, Y.FromJSON a, HasCallStack) => FilePath -> m (Either Y.ParseException a)
 readYamlFile filePath = GHC.withFrozenCallStack $ do
   void . H.annotate $ "Reading YAML file: " <> filePath
-  H.evalIO $ Y.decodeEither' @Value . LBS.toStrict <$> LBS.readFile filePath
+  H.evalIO $ Y.decodeEither' . LBS.toStrict <$> LBS.readFile filePath
 
 -- | Read the 'filePath' file as YAML.  Same as 'readYamlFile' but fails on error.
-readYamlFileOk :: (MonadTest m, MonadIO m, HasCallStack) => FilePath -> m Value
+readYamlFileOk :: forall a m. (MonadTest m, MonadIO m, Y.FromJSON a, HasCallStack) => FilePath -> m a
 readYamlFileOk filePath = GHC.withFrozenCallStack $
   H.leftFailM $ readYamlFile filePath
 
-rewriteLbsYaml :: (MonadTest m, HasCallStack) => (Value -> Value) -> LBS.ByteString -> m LBS.ByteString
+rewriteLbsYaml :: forall a m. (MonadTest m, Y.FromJSON a, Y.ToJSON a, HasCallStack) => (a -> a) -> LBS.ByteString -> m LBS.ByteString
 rewriteLbsYaml f lbs = GHC.withFrozenCallStack $ do
   case Y.decodeEither' (LBS.toStrict lbs) of
     Right iv -> return (J.encode (f iv))
     Left msg -> H.failMessage GHC.callStack (show msg)
 
 -- | Rewrite the 'filePath' YAML file using the function 'f'.
-rewriteYamlFile :: (MonadTest m, MonadIO m, HasCallStack) => FilePath -> (Value -> Value) -> m ()
+rewriteYamlFile :: forall a m. (MonadTest m, MonadIO m, Y.FromJSON a, Y.ToJSON a, HasCallStack) => FilePath -> (a -> a) -> m ()
 rewriteYamlFile filePath f = GHC.withFrozenCallStack $ do
   void . H.annotate $ "Rewriting YAML file: " <> filePath
   lbsReadFile filePath >>= rewriteLbsYaml f >>= lbsWriteFile filePath
 
 -- | Rewrite the 'filePath' YAML file using the function 'f'.
-copyRewriteYamlFile :: (MonadTest m, MonadIO m, HasCallStack) => FilePath -> FilePath -> (Value -> Value) -> m ()
+copyRewriteYamlFile :: forall a m. (MonadTest m, MonadIO m, Y.FromJSON a, Y.ToJSON a, HasCallStack) => FilePath -> FilePath -> (a -> a) -> m ()
 copyRewriteYamlFile src dst f = GHC.withFrozenCallStack $ do
   void . H.annotate $ "Rewriting YAML from file: " <> src <> " to file " <> dst
   lbsReadFile src >>= rewriteLbsYaml f >>= lbsWriteFile dst
@@ -264,7 +266,7 @@
 -- | Assert the 'filePath' can be parsed as JSON.
 assertIsJsonFile :: (MonadTest m, MonadIO m, HasCallStack) => FilePath -> m ()
 assertIsJsonFile fp = GHC.withFrozenCallStack $ do
-  jsonResult <- readJsonFile fp
+  jsonResult <- readJsonFile @Value fp
   case jsonResult of
     Right _ -> return ()
     Left msg -> H.failMessage GHC.callStack msg
@@ -272,7 +274,7 @@
 -- | Assert the 'filePath' can be parsed as YAML.
 assertIsYamlFile :: (MonadTest m, MonadIO m, HasCallStack) => FilePath -> m ()
 assertIsYamlFile fp = GHC.withFrozenCallStack $ do
-  result <- readJsonFile fp
+  result <- readJsonFile @Value fp
   case result of
     Right _ -> return ()
     Left msg -> H.failMessage GHC.callStack msg
diff --git a/src/Hedgehog/Extras/Test/Process.hs b/src/Hedgehog/Extras/Test/Process.hs
--- a/src/Hedgehog/Extras/Test/Process.hs
+++ b/src/Hedgehog/Extras/Test/Process.hs
@@ -34,7 +34,7 @@
 import           Data.Either (Either (..))
 import           Data.Eq (Eq (..))
 import           Data.Function (($), (&), (.))
-import           Data.Functor (Functor (..))
+import           Data.Functor ((<$>))
 import           Data.Int (Int)
 import           Data.Maybe (Maybe (..))
 import           Data.Monoid (Last (..), mempty, (<>))
@@ -170,10 +170,7 @@
   case exitResult of
     IO.ExitFailure exitCode -> do
       H.annotate $ L.unlines $
-        [ "Process exited with non-zero exit-code: " ++ show @Int exitCode
-        , "━━━━ command ━━━━"
-        , pkgBin <> " " <> L.unwords (fmap argQuote arguments)
-        ]
+        [ "Process exited with non-zero exit-code: " ++ show @Int exitCode ]
         ++ (if L.null stdout then [] else ["━━━━ stdout ━━━━" , stdout])
         ++ (if L.null stderr then [] else ["━━━━ stderr ━━━━" , stderr])
       H.failMessage GHC.callStack "Execute process failed"
@@ -191,9 +188,9 @@
   -> m (ExitCode, String, String) -- ^ exit code, stdout, stderr
 execFlexAny' execConfig pkgBin envBin arguments = GHC.withFrozenCallStack $ do
   cp <- procFlex' execConfig pkgBin envBin arguments
-  H.annotate . ("Command: " <>) $ case IO.cmdspec cp of
+  H.annotate . ("━━━━ command ━━━━\n" <>) $ case IO.cmdspec cp of
     IO.ShellCommand cmd -> cmd
-    IO.RawCommand cmd args -> cmd <> " " <> L.unwords args
+    IO.RawCommand cmd args -> cmd <> " " <> L.unwords (argQuote <$> args)
   H.evalIO $ IO.readCreateProcessWithExitCode cp ""
 
 -- | Execute a process, returning '()'.
@@ -218,10 +215,7 @@
   (exitResult, stdout, stderr) <- execAny execConfig bin arguments
   case exitResult of
     IO.ExitFailure exitCode -> H.failMessage GHC.callStack . L.unlines $
-      [ "Process exited with non-zero exit-code: " ++ show @Int exitCode
-      , "━━━━ command ━━━━"
-      , bin <> " " <> L.unwords (fmap argQuote arguments)
-      ]
+      [ "Process exited with non-zero exit-code: " ++ show @Int exitCode ]
       ++ (if L.null stdout then [] else ["━━━━ stdout ━━━━" , stdout])
       ++ (if L.null stderr then [] else ["━━━━ stderr ━━━━" , stderr])
     IO.ExitSuccess -> return stdout
@@ -238,7 +232,7 @@
         { IO.env = getLast $ execConfigEnv execConfig
         , IO.cwd = getLast $ execConfigCwd execConfig
         }
-  H.annotate . ("Command: " <>) $ bin <> " " <> L.unwords arguments
+  H.annotate . ( "━━━━ command ━━━━\n" <>) $ bin <> " " <> L.unwords (argQuote <$> arguments)
   H.evalIO $ IO.readCreateProcessWithExitCode cp ""
 
 -- | Wait for process to exit.