diff --git a/app/MimaAsm/Main.hs b/app/MimaAsm/Main.hs
index c8dcbe6..bd7b34e 100644
--- a/app/MimaAsm/Main.hs
+++ b/app/MimaAsm/Main.hs
@@ -4,6 +4,7 @@ module Main where
 
 import           Control.Monad.Trans.Class
 import qualified Data.Map as Map
+import           Data.Maybe
 import qualified Data.Text as T
 import qualified Data.Text.IO as T
 import           Options.Applicative
@@ -27,10 +28,7 @@ data Settings = Settings
   } deriving (Show)
 
 getOutfile :: Settings -> FilePath
-getOutfile settings =
-  case outfile settings of
-    Just path -> path
-    Nothing   -> discoveredPath
+getOutfile settings = fromMaybe discoveredPath $ outfile settings
   where
     discoveredPath = dropExtension (infile settings) ++ ".mima"
 
@@ -38,9 +36,9 @@ getFlagFile :: Settings -> File
 getFlagFile settings =
   case flagFile settings of
     Just path -> RequiredFile path
-    Nothing   -> case discover settings of
-      False -> NoFile
-      True  -> OptionalFile discoveredPath
+    Nothing   -> if discover settings
+      then OptionalFile discoveredPath
+      else NoFile
   where
     discoveredPath = dropExtension (getOutfile settings) ++ ".mima-flags"
 
@@ -48,9 +46,9 @@ getSymbolFile :: Settings -> File
 getSymbolFile settings =
   case symbolFile settings of
     Just path -> RequiredFile path
-    Nothing   -> case discover settings of
-      False -> NoFile
-      True  -> OptionalFile discoveredPath
+    Nothing   -> if discover settings
+      then OptionalFile discoveredPath
+      else NoFile
   where
     discoveredPath = dropExtension (getOutfile settings) ++ ".mima-symbols"
 
diff --git a/app/MimaRun/Main.hs b/app/MimaRun/Main.hs
index 261c75e..85742dc 100644
--- a/app/MimaRun/Main.hs
+++ b/app/MimaRun/Main.hs
@@ -41,9 +41,9 @@ getFlagFile :: Settings -> File
 getFlagFile settings =
   case flagFile settings of
     Just path -> RequiredFile path
-    Nothing   -> case discover settings of
-      False -> NoFile
-      True  -> OptionalFile discoveredPath
+    Nothing   -> if discover settings
+      then OptionalFile discoveredPath
+      else NoFile
   where
     discoveredPath = dropExtension (infile settings) ++ ".mima-flags"
 
@@ -51,9 +51,9 @@ getSymbolFile :: Settings -> File
 getSymbolFile settings =
   case symbolFile settings of
     Just path -> RequiredFile path
-    Nothing   -> case discover settings of
-      False -> NoFile
-      True  -> OptionalFile discoveredPath
+    Nothing   -> if discover settings
+      then OptionalFile discoveredPath
+      else NoFile
   where
     discoveredPath = dropExtension (infile settings) ++ ".mima-symbols"
 
diff --git a/src/Mima/Flag.hs b/src/Mima/Flag.hs
index 4dd22f9..4e47533 100644
--- a/src/Mima/Flag.hs
+++ b/src/Mima/Flag.hs
@@ -1,4 +1,3 @@
-{-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE RecordWildCards #-}
 
 module Mima.Flag
@@ -122,7 +121,7 @@ getFlagSpec af =
       isInSet f s = flagChar f `Set.member` s
       getAddressSpec :: Flag -> AddressSpec
       getAddressSpec f = rangesToSpec $ map fst $ filter (isInSet f . snd) $ Map.assocs af
-  in  pure getAddressSpec <*> rawFlags
+  in  getAddressSpec <$> rawFlags
 
 interpretFlagSpec :: FlagSpec -> Flags (MimaAddress -> Bool)
 interpretFlagSpec spec =
diff --git a/src/Mima/Format/State.hs b/src/Mima/Format/State.hs
index c80665f..a42d52a 100644
--- a/src/Mima/Format/State.hs
+++ b/src/Mima/Format/State.hs
@@ -113,9 +113,9 @@ fAddress :: MimaAddress -> Formatter
 fAddress a = do
   env <- ask
   let conf = feConf env
-      dec = if fcShowAddressDec conf then [fAddressDec] else []
-      hex = if fcShowAddressHex conf then [fAddressHex] else []
-      bin = if fcShowAddressBin conf then [fAddressBin] else []
+      dec = [fAddressDec | fcShowAddressDec conf]
+      hex = [fAddressHex | fcShowAddressHex conf]
+      bin = [fAddressBin | fcShowAddressBin conf]
       formats = (dec ++ hex ++ bin) <*> pure a
   pure $ "[" <> T.intercalate ", " formats <> "]"
 
@@ -134,9 +134,9 @@ fWord :: MimaWord -> Formatter
 fWord a = do
   env <- ask
   let conf = feConf env
-      dec = if fcShowWordDec conf then [fWordDec] else []
-      hex = if fcShowWordHex conf then [fWordHex] else []
-      bin = if fcShowWordBin conf then [fWordBin] else []
+      dec = [fWordDec | fcShowWordDec conf]
+      hex = [fWordHex | fcShowWordHex conf]
+      bin = [fWordBin | fcShowWordBin conf]
       formats = (dec ++ hex ++ bin) <*> pure a
   pure $ "{" <> T.intercalate ", " formats <> "}"
 
diff --git a/src/Mima/Instruction.hs b/src/Mima/Instruction.hs
index c82af36..1de42e8 100644
--- a/src/Mima/Instruction.hs
+++ b/src/Mima/Instruction.hs
@@ -112,8 +112,8 @@ parseSmallInstruction mw = do
 parseSmallOpcode :: Opcode -> Either T.Text SmallOpcode
 parseSmallOpcode w = case smallOpcodeMap Map.!? w of
   Just oc -> pure oc
-  Nothing -> Left $ "Unknown small opcode " <> toDec w <> " (" <> (fixWidthHex 1 $ toHex w)
-                     <> ", " <> (fixWidthBin 4 $ toBin w) <> ")"
+  Nothing -> Left $ "Unknown small opcode " <> toDec w <> " (" <> fixWidthHex 1 (toHex w)
+                     <> ", " <> fixWidthBin 4 (toBin w) <> ")"
 
 parseLargeInstruction :: MimaWord -> Either T.Text Instruction
 parseLargeInstruction mw = do
@@ -125,8 +125,8 @@ parseLargeInstruction mw = do
 parseLargeOpcode :: Opcode -> Either T.Text LargeOpcode
 parseLargeOpcode w = case largeOpcodeMap Map.!? w of
   Just oc -> pure oc
-  Nothing -> Left $ "Unknown large opcode " <> toDec w <> " (" <> (fixWidthHex 1 $ toHex w)
-                     <> ", " <> (fixWidthBin 4 $ toBin w) <> ")"
+  Nothing -> Left $ "Unknown large opcode " <> toDec w <> " (" <> fixWidthHex 1 (toHex w)
+                     <> ", " <> fixWidthBin 4 (toBin w) <> ")"
 
 instructionToWord :: Instruction -> MimaWord
 instructionToWord (SmallInstruction so lv) = wordFromSmallOpcode (smallOpcodeNr so) lv
diff --git a/src/Mima/Load.hs b/src/Mima/Load.hs
index aee910e..2b07b65 100644
--- a/src/Mima/Load.hs
+++ b/src/Mima/Load.hs
@@ -29,11 +29,11 @@ instance Binary (LD MimaWord) where
 
 instance Binary (LD LargeValue) where
   put = put . LD . largeValueToWord . unLD
-  get = (LD . getLargeValue) <$> unLD <$> get
+  get = LD . getLargeValue . unLD <$> get
 
 instance Binary (LD MimaMemory) where
   put = mapM_ (put . LD) . memoryToWords . unLD
-  get = (LD . wordsToMemory . map unLD) <$> many get
+  get = LD . wordsToMemory . map unLD <$> many get
 
 instance Binary (LD MimaState) where
   put ldms = do
diff --git a/src/Mima/Parse/Assembly.hs b/src/Mima/Parse/Assembly.hs
index 2ac7dd0..cc504aa 100644
--- a/src/Mima/Parse/Assembly.hs
+++ b/src/Mima/Parse/Assembly.hs
@@ -36,7 +36,7 @@ almostWordToWord (ALiteral w)     = w
 
 formatAssembly :: WeedResult MimaAddress -> (MimaState, LabelSpec, RawFlags)
 formatAssembly res =
-  let mem = fmap almostWordToWord $ wrMemory res
+  let mem = almostWordToWord <$> wrMemory res
       s = registersToState (wrRegisters res) (mapToMemory mem)
   in  (s, wrLabels res, wrFlags res)
 
diff --git a/src/Mima/Parse/Assembly/RawInstruction.hs b/src/Mima/Parse/Assembly/RawInstruction.hs
index 4ca5506..2984696 100644
--- a/src/Mima/Parse/Assembly/RawInstruction.hs
+++ b/src/Mima/Parse/Assembly/RawInstruction.hs
@@ -66,7 +66,7 @@ lRawInstruction = label "instruction" $ smallInstruction <|> largeInstruction
   where
     smallInstruction = do
       so <- smallOpcode
-      void $ lSpace
+      void lSpace
       lv <- lexeme address
       pure $ RawSmallInstruction so lv
     largeInstruction = do
diff --git a/src/Mima/Parse/Assembly/Weed/Common.hs b/src/Mima/Parse/Assembly/Weed/Common.hs
index 2ee863f..2f16e5c 100644
--- a/src/Mima/Parse/Assembly/Weed/Common.hs
+++ b/src/Mima/Parse/Assembly/Weed/Common.hs
@@ -34,8 +34,8 @@ emptyRegisters = Registers
   }
 
 registersToState :: Registers MimaAddress -> MimaMemory -> MimaState
-registersToState r mem = MimaState (fromMaybe 0 $ rIAR r) (fromMaybe 0 $ rACC r)
-  (fromMaybe 0 $ rRA r) (fromMaybe 0 $ rSP r) (fromMaybe 0 $ rFP r) mem
+registersToState r = MimaState (fromMaybe 0 $ rIAR r) (fromMaybe 0 $ rACC r)
+  (fromMaybe 0 $ rRA r) (fromMaybe 0 $ rSP r) (fromMaybe 0 $ rFP r)
 
 data AlmostWord a
   = AInstruction (RawInstruction a)
diff --git a/src/Mima/Parse/Assembly/Weed/Statement.hs b/src/Mima/Parse/Assembly/Weed/Statement.hs
index 853ad2e..dd75a87 100644
--- a/src/Mima/Parse/Assembly/Weed/Statement.hs
+++ b/src/Mima/Parse/Assembly/Weed/Statement.hs
@@ -141,15 +141,14 @@ turnFlagsOff thing flags = do
 {- Weeding at a larger scale -}
 
 weedDirective :: WithOffset a -> Directive Address -> SWeed ()
-weedDirective thing d = do
-  case d of
-    DReg sr        -> setRegister thing sr
-    DOrg addr      -> setAddressTo thing addr
-    DLit w         -> addAlmostWord thing (ALiteral w)
-    DArr ws        -> mapM_ (addAlmostWord thing . ALiteral) ws
-    DFlag flags    -> setFlags thing flags
-    DFlagOn flags  -> turnFlagsOn thing flags
-    DFlagOff flags -> turnFlagsOff thing flags
+weedDirective thing d = case d of
+  DReg sr        -> setRegister thing sr
+  DOrg addr      -> setAddressTo thing addr
+  DLit w         -> addAlmostWord thing (ALiteral w)
+  DArr ws        -> mapM_ (addAlmostWord thing . ALiteral) ws
+  DFlag flags    -> setFlags thing flags
+  DFlagOn flags  -> turnFlagsOn thing flags
+  DFlagOff flags -> turnFlagsOff thing flags
 
 weedInstruction :: WithOffset a -> RawInstruction Address -> SWeed ()
 weedInstruction thing i = addAlmostWord thing $ AInstruction i
@@ -164,7 +163,7 @@ weedStep thing =
 weedStatements :: [WithOffset (Statement Address)] -> Weed WeedError (WeedResult Address)
 weedStatements statements = do
   result <- execStateT (mapM_ weedStep statements) initialState
-  when (not $ Set.null $ wsOpenFlags result)
+  unless (Set.null $ wsOpenFlags result)
     $ harmless
     $ errorAt' (lastOffset statements)
     $ "Flags were never closed: " ++ T.unpack (formatFlagSet (wsOpenFlags result))
diff --git a/src/Mima/Parse/FlagFile.hs b/src/Mima/Parse/FlagFile.hs
index a3cac8b..d047048 100644
--- a/src/Mima/Parse/FlagFile.hs
+++ b/src/Mima/Parse/FlagFile.hs
@@ -41,4 +41,4 @@ parseFlagFile :: Parser RawFlags
 parseFlagFile = space *> many lNewline *> (Map.fromList <$> many lLine) <* hidden eof
 
 readFlagFile :: FilePath -> T.Text -> Either WeedErrorBundle RawFlags
-readFlagFile filename input = parse parseFlagFile filename input
+readFlagFile = parse parseFlagFile
diff --git a/src/Mima/Parse/Weed.hs b/src/Mima/Parse/Weed.hs
index 9ae0374..606c93c 100644
--- a/src/Mima/Parse/Weed.hs
+++ b/src/Mima/Parse/Weed.hs
@@ -1,5 +1,3 @@
-{-# LANGUAGE GeneralizedNewtypeDeriving #-}
-
 module Mima.Parse.Weed
   ( Weed
   , runWeed
@@ -94,7 +92,7 @@ withOffset :: Parser a -> Parser (WithOffset a)
 withOffset p = WithOffset <$> getOffset <*> p
 
 errorAt :: WithOffset a -> String -> WeedError
-errorAt wo errorMsg = errorAt' (woOffset wo) errorMsg
+errorAt wo = errorAt' (woOffset wo)
 
 errorAt' :: Int -> String -> WeedError
 errorAt' o errorMsg = errorsAt' o [errorMsg]
diff --git a/src/Mima/State.hs b/src/Mima/State.hs
index 87f1d2f..7638753 100644
--- a/src/Mima/State.hs
+++ b/src/Mima/State.hs
@@ -45,10 +45,10 @@ wordsToMemory = mapToMemory
               . zip [minBound..]
 
 memoryToWords :: MimaMemory -> [MimaWord]
-memoryToWords mem = map (\addr -> readAt addr mem) $ continuousUsedAddresses mem
+memoryToWords mem = map (`readAt` mem) $ continuousUsedAddresses mem
 
 maxAddress :: MimaMemory -> MimaAddress
-maxAddress (MimaMemory m) = fromMaybe minBound $ fst <$> Map.lookupMax m
+maxAddress (MimaMemory m) = maybe minBound fst $ Map.lookupMax m
 
 usedAddresses :: MimaMemory -> [MimaAddress]
 usedAddresses (MimaMemory m) = Map.keys m
@@ -178,7 +178,7 @@ step' :: Flags (MimaAddress -> Bool) -> MimaState -> Either AbortReason MimaStat
 step' flags ms = runExecution flags $ step ms
 
 run :: Flags (MimaAddress -> Bool) -> MimaState -> (MimaState, AbortReason, Integer)
-run f ms = helper 0 ms
+run f = helper 0
   where
     helper completed s =
       case step' f s of
@@ -186,7 +186,7 @@ run f ms = helper 0 ms
         Right s' -> helper (completed + 1) s'
 
 runN :: Flags (MimaAddress -> Bool) -> Integer -> MimaState -> (MimaState, Maybe AbortReason, Integer)
-runN f n ms = helper 0 ms
+runN f n = helper 0
   where
     helper completed s =
       if completed >= n
diff --git a/src/Mima/Util.hs b/src/Mima/Util.hs
index 551fd43..e558b0d 100644
--- a/src/Mima/Util.hs
+++ b/src/Mima/Util.hs
@@ -1,6 +1,4 @@
 {-# LANGUAGE FlexibleInstances #-}
-{-# LANGUAGE OverloadedStrings #-}
-{-# LANGUAGE TypeSynonymInstances #-}
 
 module Mima.Util
   (