diff --git a/feedback.cabal b/feedback.cabal
--- a/feedback.cabal
+++ b/feedback.cabal
@@ -5,7 +5,7 @@
 -- see: https://github.com/sol/hpack
 
 name:           feedback
-version:        0.1.0.5
+version:        0.2.0.0
 synopsis:       Declarative feedback loop manager
 homepage:       https://github.com/NorfairKing/feedback#readme
 bug-reports:    https://github.com/NorfairKing/feedback/issues
diff --git a/src/Feedback/Common/OptParse.hs b/src/Feedback/Common/OptParse.hs
--- a/src/Feedback/Common/OptParse.hs
+++ b/src/Feedback/Common/OptParse.hs
@@ -1,4 +1,3 @@
-{-# LANGUAGE DeriveGeneric #-}
 {-# LANGUAGE DerivingVia #-}
 {-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE OverloadedLists #-}
@@ -16,9 +15,7 @@
 import Data.Maybe
 import qualified Data.Text as T
 import Data.Version
-import Data.Yaml (FromJSON, ToJSON)
 import qualified Env
-import GHC.Generics (Generic)
 import Options.Applicative as OptParse
 import qualified Options.Applicative.Help as OptParse (pretty)
 import Path
@@ -31,7 +28,7 @@
     loopSettingOutputSettings :: !OutputSettings,
     loopSettingHooksSettings :: !HooksSettings
   }
-  deriving (Show, Eq, Generic)
+  deriving (Show)
 
 combineToLoopSettings :: Flags -> Environment -> Maybe OutputConfiguration -> LoopConfiguration -> IO LoopSettings
 combineToLoopSettings Flags {..} Environment {} mDefaultOutputConfig LoopConfiguration {..} = do
@@ -48,7 +45,7 @@
     runSettingExtraEnv :: !(Map String String),
     runSettingWorkingDir :: !(Maybe (Path Abs Dir))
   }
-  deriving (Show, Eq, Generic)
+  deriving (Show)
 
 combineToRunSettings :: RunConfiguration -> IO RunSettings
 combineToRunSettings RunConfiguration {..} = do
@@ -61,7 +58,7 @@
   { filterSettingGitignore :: !Bool,
     filterSettingFind :: !(Maybe String)
   }
-  deriving (Show, Eq, Generic)
+  deriving (Show)
 
 combineToFilterSettings :: FilterConfiguration -> FilterSettings
 combineToFilterSettings FilterConfiguration {..} =
@@ -72,7 +69,7 @@
 data OutputSettings = OutputSettings
   { outputSettingClear :: !Clear
   }
-  deriving (Show, Eq, Generic)
+  deriving (Show)
 
 combineToOutputSettings :: OutputFlags -> OutputConfiguration -> OutputSettings
 combineToOutputSettings OutputFlags {..} mConf =
@@ -85,7 +82,7 @@
   { hooksSettingBeforeAll :: Maybe RunSettings,
     hooksSettingAfterFirst :: Maybe RunSettings
   }
-  deriving (Show, Eq, Generic)
+  deriving (Show)
 
 combineToHooksSettings :: HooksConfiguration -> IO HooksSettings
 combineToHooksSettings HooksConfiguration {..} = do
@@ -97,8 +94,6 @@
   { configLoops :: !(Map String LoopConfiguration),
     configOutputConfiguration :: !(Maybe OutputConfiguration)
   }
-  deriving stock (Show, Eq, Generic)
-  deriving (FromJSON, ToJSON) via (Autodocodec Configuration)
 
 instance HasCodec Configuration where
   codec =
@@ -123,8 +118,7 @@
     loopConfigOutputConfiguration :: !OutputConfiguration,
     loopConfigHooksConfiguration :: !HooksConfiguration
   }
-  deriving stock (Show, Eq, Generic)
-  deriving (FromJSON, ToJSON) via (Autodocodec LoopConfiguration)
+  deriving (Eq)
 
 instance HasCodec LoopConfiguration where
   codec =
@@ -192,8 +186,7 @@
     runConfigExtraEnv :: !(Map String String),
     runConfigWorkingDir :: !(Maybe FilePath)
   }
-  deriving stock (Show, Eq, Generic)
-  deriving (FromJSON, ToJSON) via (Autodocodec RunConfiguration)
+  deriving (Eq)
 
 instance HasCodec RunConfiguration where
   codec =
@@ -234,8 +227,7 @@
   { filterConfigGitignore :: !(Maybe Bool),
     filterConfigFind :: !(Maybe String)
   }
-  deriving stock (Show, Eq, Generic)
-  deriving (FromJSON, ToJSON) via (Autodocodec FilterConfiguration)
+  deriving (Eq)
 
 instance HasCodec FilterConfiguration where
   codec =
@@ -269,8 +261,7 @@
 data OutputConfiguration = OutputConfiguration
   { outputConfigClear :: !(Maybe Clear)
   }
-  deriving stock (Show, Eq, Generic)
-  deriving (FromJSON, ToJSON) via (Autodocodec OutputConfiguration)
+  deriving (Eq)
 
 instance HasCodec OutputConfiguration where
   codec =
@@ -299,7 +290,7 @@
   { hooksConfigurationBeforeAll :: !(Maybe RunConfiguration),
     hooksConfigurationAfterFirst :: !(Maybe RunConfiguration)
   }
-  deriving (Show, Eq, Generic)
+  deriving (Eq)
 
 instance HasCodec HooksConfiguration where
   codec =
@@ -339,7 +330,6 @@
 data Environment = Environment
   { envConfigFile :: !(Maybe FilePath)
   }
-  deriving (Show, Eq, Generic)
 
 getEnvironment :: IO Environment
 getEnvironment = Env.parse (Env.header "Environment") environmentParser
@@ -386,13 +376,11 @@
     flagConfigFile :: !(Maybe FilePath),
     flagOutputFlags :: !OutputFlags
   }
-  deriving (Show, Eq, Generic)
 
 data OutputFlags = OutputFlags
   { outputFlagClear :: !(Maybe Clear),
     outputFlagDebug :: Bool
   }
-  deriving (Show, Eq, Generic)
 
 parseFlags :: OptParse.Parser Flags
 parseFlags =
@@ -440,7 +428,7 @@
       )
 
 newtype Command = CommandScript {unScript :: String}
-  deriving (Show, Eq, Generic)
+  deriving (Show, Eq)
 
 instance HasCodec Command where
   codec = dimapCodec CommandScript unScript codec
@@ -452,7 +440,7 @@
     (requiredField "command" "the command to run on change (alias for 'script' for backward compatibility)")
 
 data Clear = ClearScreen | DoNotClearScreen
-  deriving (Show, Eq, Generic)
+  deriving (Show, Eq)
 
 instance HasCodec Clear where
   codec = dimapCodec f g codec
diff --git a/src/Feedback/Common/Output.hs b/src/Feedback/Common/Output.hs
--- a/src/Feedback/Common/Output.hs
+++ b/src/Feedback/Common/Output.hs
@@ -37,9 +37,6 @@
 loopNameChunk :: String -> Chunk
 loopNameChunk = fore yellow . chunk . T.pack
 
-commandChunk :: String -> Chunk
-commandChunk = fore blue . chunk . T.pack
-
 startingLines :: RunSettings -> [[Chunk]]
 startingLines RunSettings {..} =
   let RunSettings _ _ _ = undefined
diff --git a/src/Feedback/Loop.hs b/src/Feedback/Loop.hs
--- a/src/Feedback/Loop.hs
+++ b/src/Feedback/Loop.hs
@@ -150,18 +150,7 @@
 
   -- Set up the fsnotify watchers based on that filter
   sendOutput OutputWatching
-  let descendHandler :: Path Abs Dir -> [Path Abs Dir] -> [Path Abs File] -> IO (WalkAction Abs)
-      descendHandler dir subdirs _ =
-        -- Don't descent into hidden directories
-        pure $ WalkExclude $ filter (isHiddenIn dir) subdirs
-      outputWriter :: Path Abs Dir -> [Path Abs Dir] -> [Path Abs File] -> IO StopListening
-      outputWriter dir _ _ =
-        if filterDirFilter f dir
-          then do
-            let eventFilter fsEvent = maybe False (filterFileFilter f) $ parseAbsFile (eventPath fsEvent)
-            watchDirChan watchManager (fromAbsDir dir) eventFilter eventChan
-          else pure (pure ())
-  walkDirAccum (Just descendHandler) outputWriter here
+  watchBasedOnFilter here watchManager eventChan f
 
 #ifdef MIN_VERSION_safe_coloured_text_terminfo
 getTermCaps :: IO TerminalCapabilities
@@ -174,7 +163,6 @@
 data RestartEvent
   = FSEvent !FS.Event
   | StdinEvent !Char
-  deriving (Show, Eq)
 
 worker ::
   ThreadId ->
@@ -308,7 +296,6 @@
   | OutputKilled
   | OutputProcessStarted !RunSettings
   | OutputProcessExited !ExitCode !Word64
-  deriving (Show)
 
 putOutput :: OutputSettings -> TerminalCapabilities -> ZonedTime -> Output -> IO ()
 putOutput OutputSettings {..} terminalCapabilities loopBegin =
diff --git a/src/Feedback/Loop/Filter.hs b/src/Feedback/Loop/Filter.hs
--- a/src/Feedback/Loop/Filter.hs
+++ b/src/Feedback/Loop/Filter.hs
@@ -1,4 +1,5 @@
 {-# LANGUAGE CPP #-}
+{-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE QuasiQuotes #-}
 {-# LANGUAGE RecordWildCards #-}
@@ -13,7 +14,10 @@
 import qualified Data.Conduit.Combinators as C
 import qualified Data.Conduit.List as CL
 import Data.List
-import Data.Set
+import Data.Map (Map)
+import qualified Data.Map as M
+import Data.Maybe
+import Data.Set (Set)
 import qualified Data.Set as S
 import qualified Data.Text as T
 import qualified Data.Text.Encoding as TE
@@ -21,6 +25,7 @@
 import Path
 import Path.IO
 import System.Exit
+import System.FSNotify as FS
 import System.Process.Typed as Typed
 #ifdef MIN_VERSION_Win32
 import System.Win32.MinTTY (isMinTTYHandle)
@@ -36,29 +41,26 @@
 getMinTTY = pure False
 #endif
 
-data Filter = Filter
-  { filterDirFilter :: Path Abs Dir -> Bool,
-    filterFileFilter :: Path Abs File -> Bool
-  }
+data Filter
+  = FilterWatchlist !(Set (Path Abs File))
+  | FilterPredicate !(Path Abs Dir -> Bool) !(Path Abs File -> Bool)
 
 instance Semigroup Filter where
-  f1 <> f2 =
-    Filter
-      { filterDirFilter = \d -> filterDirFilter f1 d && filterDirFilter f2 d,
-        filterFileFilter = \f -> filterFileFilter f1 f && filterFileFilter f2 f
-      }
+  f1 <> f2 = case (f1, f2) of
+    (FilterWatchlist s1, FilterWatchlist s2) -> FilterWatchlist (S.intersection s1 s2)
+    (FilterWatchlist s, FilterPredicate dirPredicate filePredicate) ->
+      FilterWatchlist $ S.filter filePredicate $ S.filter (dirPredicate . parent) s
+    (FilterPredicate dirPredicate filePredicate, FilterWatchlist s) ->
+      FilterWatchlist $ S.filter filePredicate $ S.filter (dirPredicate . parent) s
+    (FilterPredicate dirPredicate1 filePredicate1, FilterPredicate dirPredicate2 filePredicate2) ->
+      FilterPredicate (\d -> dirPredicate1 d && dirPredicate2 d) (\f -> filePredicate1 f && filePredicate2 f)
 
 instance Monoid Filter where
-  mempty = Filter {filterDirFilter = const True, filterFileFilter = const True}
+  mempty = FilterPredicate (const True) (const True)
   mappend = (<>)
 
 fileSetFilter :: Set (Path Abs File) -> Filter
-fileSetFilter fileSet =
-  let dirSet = S.map parent fileSet
-   in Filter
-        { filterDirFilter = (`S.member` dirSet),
-          filterFileFilter = (`S.member` fileSet)
-        }
+fileSetFilter = FilterWatchlist
 
 mkCombinedFilter :: Path Abs Dir -> FilterSettings -> IO Filter
 mkCombinedFilter here filterSettings =
@@ -94,13 +96,20 @@
 gitLsFiles here = do
   -- If there is no git directory, we'll get a 'fatal' message on stderr.
   -- We don't need the user to see this, so we setStderr nullStream.
-  let processConfig = setStderr nullStream $ shell "git ls-files"
+  let processConfig = setStderr nullStream $ shell "git ls-files -z"
   (ec, out) <- readProcessStdout processConfig
-  set <- bytesFileSet here out
+  set <- nullBytesFileSet here out
   pure $ case ec of
     ExitFailure _ -> Nothing
     ExitSuccess -> Just set
 
+nullBytesFileSet :: Path Abs Dir -> LB.ByteString -> IO (Set (Path Abs File))
+nullBytesFileSet here lb =
+  runConduit $
+    CL.sourceList (LB8.split '\NUL' lb)
+      .| C.map LB.toStrict
+      .| fileSetBuilder here
+
 mkFindFilter :: Path Abs Dir -> FilterSettings -> IO Filter
 mkFindFilter here FilterSettings {..} = case filterSettingFind of
   Nothing -> pure mempty
@@ -110,13 +119,13 @@
 filesFromFindArgs here args = do
   let processConfig = setStdout createPipe $ shell $ "find " <> args
   (ec, out) <- readProcessStdout processConfig
-  set <- bytesFileSet here out
+  set <- lineBytesFileSet here out
   case ec of
     ExitFailure _ -> die $ "Find failed: " <> show ec
     ExitSuccess -> pure set
 
-bytesFileSet :: Path Abs Dir -> LB.ByteString -> IO (Set (Path Abs File))
-bytesFileSet here lb =
+lineBytesFileSet :: Path Abs Dir -> LB.ByteString -> IO (Set (Path Abs File))
+lineBytesFileSet here lb =
   runConduit $
     CL.sourceList (LB8.lines lb)
       .| C.map LB.toStrict
@@ -138,29 +147,54 @@
 
 standardFilter :: Path Abs Dir -> Filter
 standardFilter here =
-  Filter
-    { filterDirFilter = not . isHiddenIn here,
-      filterFileFilter = \f ->
+  FilterPredicate
+    (not . isHiddenIn here)
+    ( \f ->
         and
           [ not $ isHiddenIn here f,
             -- It's not one of those files that vim makes
             not $ "~" `isSuffixOf` fromAbsFile f,
             filename f /= [relfile|4913|]
           ]
-    }
-
-hidden :: Path Rel File -> Bool
-hidden = goFile
-  where
-    goFile :: Path Rel File -> Bool
-    goFile f = isHiddenIn (parent f) f || goDir (parent f)
-    goDir :: Path Rel Dir -> Bool
-    goDir f
-      | parent f == f = False
-      | otherwise = isHiddenIn (parent f) f || goDir (parent f)
+    )
 
 isHiddenIn :: Path b Dir -> Path b t -> Bool
 isHiddenIn curdir ad =
   case stripProperPrefix curdir ad of
     Nothing -> False
     Just rp -> "." `isPrefixOf` toFilePath rp
+
+watchBasedOnFilter :: Path Abs Dir -> WatchManager -> Chan FS.Event -> Filter -> IO StopListening
+watchBasedOnFilter here watchManager eventChan = \case
+  -- If we have a watchlist of all the, then we don't need to list any files.
+  -- We just watch all the relevant directories.
+  FilterWatchlist fileSet -> do
+    let dirMap :: Map (Path Abs Dir) (Set (Path Rel File))
+        dirMap =
+          M.unionsWith S.union $
+            map (\f -> M.singleton (parent f) (S.singleton (filename f))) $
+              S.toList fileSet
+        subdirPredicate :: Path Abs Dir -> Set (Path Rel File) -> Event -> Bool
+        subdirPredicate subdir subFileSet e = fromMaybe False $ do
+          absFile <- parseAbsFile $ eventPath e
+          relFile <- stripProperPrefix subdir absFile
+          pure $ S.member relFile subFileSet
+        watchSubdir :: Path Abs Dir -> Set (Path Rel File) -> IO StopListening
+        watchSubdir subdir subFileSet = do
+          watchDirChan watchManager (fromAbsDir subdir) (subdirPredicate subdir subFileSet) eventChan
+    mconcat <$> mapM (uncurry watchSubdir) (M.toList dirMap)
+  -- If we use a predicate then we have no choice but to walk the directory tree.
+  FilterPredicate dirPredicate filePredicate ->
+    let descendHandler :: Path Abs Dir -> [Path Abs Dir] -> [Path Abs File] -> IO (WalkAction Abs)
+        descendHandler dir subdirs _ =
+          pure $
+            WalkExclude $
+              -- Don't descend into directories that are not in the filter, so we don't spend time listing them.
+              filter (not . dirPredicate) $
+                -- Don't descent into hidden directories
+                filter (isHiddenIn dir) subdirs
+        outputWriter :: Path Abs Dir -> [Path Abs Dir] -> [Path Abs File] -> IO StopListening
+        outputWriter dir _ _ = do
+          let eventFilter fsEvent = maybe False filePredicate $ parseAbsFile (eventPath fsEvent)
+          watchDirChan watchManager (fromAbsDir dir) eventFilter eventChan
+     in walkDirAccum (Just descendHandler) outputWriter here
diff --git a/src/Feedback/Loop/OptParse.hs b/src/Feedback/Loop/OptParse.hs
--- a/src/Feedback/Loop/OptParse.hs
+++ b/src/Feedback/Loop/OptParse.hs
@@ -70,7 +70,7 @@
       [""],
       layoutAsTable
         ( map
-            (uncurry loopConfigLine)
+            (pure . uncurry loopConfigLine)
             (M.toList (configLoops conf))
         ),
       [fore blue "Run ", fore yellow "feedback loopname", fore blue " to activate a feedback loop."]
@@ -78,6 +78,7 @@
 
 loopConfigLine :: String -> LoopConfiguration -> [Chunk]
 loopConfigLine loopName LoopConfiguration {..} =
-  [ loopNameChunk $ loopName <> ":",
+  [ loopNameChunk loopName,
+    ": ",
     maybe "no description" (chunk . T.pack) loopConfigDescription
   ]
diff --git a/src/Feedback/Test/OptParse.hs b/src/Feedback/Test/OptParse.hs
--- a/src/Feedback/Test/OptParse.hs
+++ b/src/Feedback/Test/OptParse.hs
@@ -18,7 +18,7 @@
 data TestSettings = TestSettings
   { testSettingLoops :: !(Map String LoopSettings)
   }
-  deriving (Show, Eq)
+  deriving (Show)
 
 combineToTestSettings :: Flags -> Environment -> Maybe Configuration -> IO TestSettings
 combineToTestSettings flags@Flags {..} environment mConf = do