diff --git a/src/YamlParse/Applicative/Explain.hs b/src/YamlParse/Applicative/Explain.hs
--- a/src/YamlParse/Applicative/Explain.hs
+++ b/src/YamlParse/Applicative/Explain.hs
@@ -63,6 +63,8 @@
         FieldParserRequired p -> FieldSchema k True Nothing $ go p
         FieldParserOptional p -> FieldSchema k False Nothing $ go p
         FieldParserOptionalWithDefault p d -> FieldSchema k False (Just $ T.pack $ show d) $ go p
+        FieldParserOptionalOrNull p -> FieldSchema k False Nothing $ go p
+        FieldParserOptionalOrNullWithDefault p d -> FieldSchema k False (Just $ T.pack $ show d) $ go p
       ParseList p -> ListSchema $ go p
       ParseMap p -> MapSchema $ go p
       ParseMapKeys _ p -> MapKeysSchema $ go p
diff --git a/src/YamlParse/Applicative/IO.hs b/src/YamlParse/Applicative/IO.hs
--- a/src/YamlParse/Applicative/IO.hs
+++ b/src/YamlParse/Applicative/IO.hs
@@ -51,11 +51,11 @@
                         [ "Reference: ",
                           T.unpack $ prettyColourisedSchema $ explainParser (yamlSchema :: YamlParser a)
                         ]
-                  die
-                    $ unlines
-                    $ concat
-                      [ failedMsgs,
-                        triedFilesMsgs,
-                        referenceMsgs
-                      ]
+                  die $
+                    unlines $
+                      concat
+                        [ failedMsgs,
+                          triedFilesMsgs,
+                          referenceMsgs
+                        ]
                 Right (ViaYamlSchema conf) -> pure $ Just conf
diff --git a/src/YamlParse/Applicative/Implement.hs b/src/YamlParse/Applicative/Implement.hs
--- a/src/YamlParse/Applicative/Implement.hs
+++ b/src/YamlParse/Applicative/Implement.hs
@@ -66,12 +66,20 @@
         FieldParserRequired p -> do
           v <- o Yaml..: key
           go p v
-        FieldParserOptional p -> do
+        FieldParserOptional p ->
+          case HM.lookup key o of
+            Nothing -> pure Nothing
+            Just v -> Just <$> go p v
+        FieldParserOptionalWithDefault p d ->
+          case HM.lookup key o of
+            Nothing -> pure d
+            Just v -> go p v
+        FieldParserOptionalOrNull p -> do
           mv <- o Yaml..:? key
           case mv of
             Nothing -> pure Nothing
             Just v -> Just <$> go p v
-        FieldParserOptionalWithDefault p d -> do
+        FieldParserOptionalOrNullWithDefault p d -> do
           mv <- o Yaml..:? key
           case mv of
             Nothing -> pure d
diff --git a/src/YamlParse/Applicative/Parser.hs b/src/YamlParse/Applicative/Parser.hs
--- a/src/YamlParse/Applicative/Parser.hs
+++ b/src/YamlParse/Applicative/Parser.hs
@@ -120,6 +120,8 @@
   FieldParserRequired :: YamlParser o -> FieldParser o
   FieldParserOptional :: YamlParser o -> FieldParser (Maybe o)
   FieldParserOptionalWithDefault :: Show o => YamlParser o -> o -> FieldParser o
+  FieldParserOptionalOrNull :: YamlParser o -> FieldParser (Maybe o)
+  FieldParserOptionalOrNullWithDefault :: Show o => YamlParser o -> o -> FieldParser o
 
 type YamlParser a = Parser Yaml.Value a
 
@@ -253,23 +255,23 @@
 
 -- | A parser for an optional field at a given key with a parser for what is found at that key
 optionalFieldWith :: Text -> Text -> YamlParser a -> ObjectParser (Maybe a)
-optionalFieldWith k h func = ParseComment h $ ParseField k $ FieldParserOptional func
+optionalFieldWith k h func = ParseComment h $ ParseField k $ FieldParserOptionalOrNull func
 
 -- | A parser for an optional field at a given key with a parser for what is found at that key without a help text
 optionalFieldWith' :: Text -> YamlParser a -> ObjectParser (Maybe a)
-optionalFieldWith' k func = ParseField k $ FieldParserOptional func
+optionalFieldWith' k func = ParseField k $ FieldParserOptionalOrNull func
 
 -- | A parser for an optional field at a given key with a default value and a parser for what is found at that key
 --
 -- For the sake of documentation, the default value needs to be showable.
 optionalFieldWithDefaultWith :: Show a => Text -> a -> Text -> YamlParser a -> ObjectParser a
-optionalFieldWithDefaultWith k d h func = ParseComment h $ ParseField k $ FieldParserOptionalWithDefault func d
+optionalFieldWithDefaultWith k d h func = ParseComment h $ ParseField k $ FieldParserOptionalOrNullWithDefault func d
 
 -- | A parser for an optional field at a given key with a default value and a parser for what is found at that key without a help text
 --
 -- For the sake of documentation, the default value needs to be showable.
 optionalFieldWithDefaultWith' :: Show a => Text -> a -> YamlParser a -> ObjectParser a
-optionalFieldWithDefaultWith' k d func = ParseField k $ FieldParserOptionalWithDefault func d
+optionalFieldWithDefaultWith' k d func = ParseField k $ FieldParserOptionalOrNullWithDefault func d
 
 -- | Make a parser that parses a value using the given extra parsing function
 --
diff --git a/yamlparse-applicative.cabal b/yamlparse-applicative.cabal
--- a/yamlparse-applicative.cabal
+++ b/yamlparse-applicative.cabal
@@ -5,7 +5,7 @@
 -- see: https://github.com/sol/hpack
 
 name:           yamlparse-applicative
-version:        0.1.0.3
+version:        0.1.0.4
 synopsis:       Declaritive configuration parsing with free docs
 description:    See https://github.com/NorfairKing/yamlparse-applicative
 homepage:       https://github.com/NorfairKing/yamlparse-applicative#readme