diff --git a/.gitignore b/.gitignore
index 7553075..b024b1b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,5 @@
 dist
+dist-newstyle
 .DS_Store
 *.ly
 *.pdf
@@ -6,3 +7,8 @@ dist
 .hackette
 .ackoptions
 *sandbox.config
+.stack-work/
+.cabal.project.local
+.cabal.project.local~
+.envrc
+.direnv
diff --git a/Setup.lhs b/Setup.lhs
old mode 100755
new mode 100644
diff --git a/music-pitch.cabal b/music-pitch.cabal
old mode 100755
new mode 100644
index 76949f4..fcee6b3
--- a/music-pitch.cabal
+++ b/music-pitch.cabal
@@ -26,13 +26,13 @@ library
                         containers,
                         lens                    >= 4.11     && < 5,
                         semigroups              >= 0.13.0.1 && < 1,
-                        data-interval           >= 1.0.0    && < 2,
+                        data-interval           >= 1.0.0    && < 3,
                         vector-space            >= 0.10.2   && < 1,
                         vector-space-points     >= 0.2      && < 1,
                         nats,
                         positive                >= 0.4      && < 1,
                         type-unary              >= 0.2.16   && < 1.0,
-                        aeson                   >= 0.7.0.6  && < 1
+                        aeson                   >= 0.7.0.6  && < 2
     exposed-modules:    Music.Pitch
                         Music.Pitch.Absolute
                         Music.Pitch.Equal
diff --git a/sketch/synopsis.hs b/sketch/synopsis.hs
index 0121325..18c50d0 100644
--- a/sketch/synopsis.hs
+++ b/sketch/synopsis.hs
@@ -5,7 +5,7 @@ data    Mode a     = Mode [Diff a] (Diff a)         -- intervals, repeat (usuall
 data    Scale a    = Scale a (Mode a)              -- root, mode
 data    Function a = Function [Diff a] (Diff a) -- intervals, repeat, repeat (usually octave)
 data    Chord a    = Chord a (Function a)          -- root, function 
-data    Ambitus a  = Ambitus a a | Ambitus a (Diff a) | Ambitus (Diff a) a
+data    Ambitus a  = Ambitus a a | Ambitus a (Diff a) | Ambitus (Diff a) a
 
 newtype ChromaticSteps = ChromaticSteps { getChromaticSteps :: Integer }
 newtype DiatonicSteps = DiatonicSteps { getDiatonicSteps :: Integer }
diff --git a/src/Music/Pitch.hs b/src/Music/Pitch.hs
index 2dff3ec..73035a8 100644
--- a/src/Music/Pitch.hs
+++ b/src/Music/Pitch.hs
@@ -1,5 +1,5 @@
 
--- | Standard pitch representation.
+-- | Standard pitch representation.
 module Music.Pitch (
         module Data.Semigroup,
         module Data.VectorSpace,
diff --git a/src/Music/Pitch/Absolute.hs b/src/Music/Pitch/Absolute.hs
index c5fdec0..b4de213 100644
--- a/src/Music/Pitch/Absolute.hs
+++ b/src/Music/Pitch/Absolute.hs
@@ -97,15 +97,15 @@ instance HasFrequency Fifths where
 instance HasFrequency Cents where
   frequency (Cents f)   =  (2/1) ** (f / 1200)
 
--- | Convert a frequency to octaves.
+-- | Convert a frequency to octaves.
 octaves :: HasFrequency a => a -> Octaves
 octaves a = Octaves $ logBase (2/1) (frequency a)
 
--- | Convert a frequency to fifths.
+-- | Convert a frequency to fifths.
 fifths :: HasFrequency a => a -> Fifths
 fifths a = Fifths $ logBase (3/2) (frequency a)
 
--- | Convert a frequency to cents.
+-- | Convert a frequency to cents.
 cents :: HasFrequency a => a -> Cents
 cents a = Cents $ logBase (2/1) (frequency a) * 1200
 
diff --git a/src/Music/Pitch/Ambitus.hs b/src/Music/Pitch/Ambitus.hs
index c79b40a..17b74cb 100644
--- a/src/Music/Pitch/Ambitus.hs
+++ b/src/Music/Pitch/Ambitus.hs
@@ -40,8 +40,8 @@ ambitus = iso toA unA . _Unwrapped
     unA a = case (I.lowerBound a, I.upperBound a) of
       (Finite m, Finite n) -> (m, n)
       -- FIXME this can happen as empty span can be represented as PosInf..NegInf
-      -- _                    -> error $ "Strange ambitus: " ++ show (I.lowerBound a, I.upperBound a)
-      _                    -> error $ "Strange ambitus"
+      -- _                    -> error $ "Strange ambitus: " ++ show (I.lowerBound a, I.upperBound a)
+      _                    -> error $ "Strange ambitus"
 
 -- ambitus' :: (Num a, Ord a) => Iso' (a, a) (Ambitus a)
 -- ambitus' = ambitus
diff --git a/src/Music/Pitch/Clef.hs b/src/Music/Pitch/Clef.hs
index 5b34a3c..cd0e108 100644
--- a/src/Music/Pitch/Clef.hs
+++ b/src/Music/Pitch/Clef.hs
@@ -67,7 +67,7 @@ instance Show Clef where
     | x == altoClef         = "altoClef"
     | x == tenorClef        = "tenorClef"
     | x == baritoneClef     = "baritoneClef"
-    | otherwise             = show a
+    | otherwise             = show a
     
 -- | Return the English name of the given clef.
 symbolName :: ClefSymbol -> String
@@ -77,7 +77,7 @@ symbolName FClef       = "F clef"
 symbolName PercClef    = "Percussion clef"
 symbolName NeutralClef = "Neutral clef"
 
--- | Return the pitch implied by the given clef at the middle space or line.
+-- | Return the pitch implied by the given clef at the middle space or line.
 symbolPitch :: ClefSymbol -> Maybe Pitch
 symbolPitch GClef = Just b'
 symbolPitch CClef = Just c
@@ -118,17 +118,17 @@ Map this to Pitch.Common
 
 -- | Standard treble clef.
 trebleClef :: Clef
--- | Standard bass clef.
+-- | Standard bass clef.
 bassClef :: Clef
--- | Standard soprano clef.
+-- | Standard soprano clef.
 sopranoClef :: Clef
--- | Standard mezzo soprano clef.
+-- | Standard mezzo soprano clef.
 mezzoSopranoClef :: Clef
--- | Standard alto clef.
+-- | Standard alto clef.
 altoClef :: Clef
--- | Standard tenor clef.
+-- | Standard tenor clef.
 tenorClef :: Clef
--- | Standard baritone clef.
+-- | Standard baritone clef.
 baritoneClef :: Clef
 trebleClef        = Clef (GClef, -1 :: ClefOctave, -1 :: ClefLine)
 bassClef          = Clef (FClef, 1  :: ClefOctave, -1 :: ClefLine)
@@ -140,11 +140,11 @@ baritoneClef      = Clef (CClef, 0  :: ClefOctave, 2  :: ClefLine)
 
 -- | Is this a clef used in contemporary notation?
 isModernClef :: Clef -> Bool
-isModernClef x | x == trebleClef  = True
-isModernClef x | x == bassClef    = True
-isModernClef x | x == altoClef    = True
-isModernClef x | x == tenorClef   = True
-isModernClef x | otherwise        = False
+isModernClef x | x == trebleClef  = True
+isModernClef x | x == bassClef    = True
+isModernClef x | x == altoClef    = True
+isModernClef x | x == tenorClef   = True
+isModernClef x | otherwise        = False
 
 -- | Is this an historical clef?
 isHistoricalClef :: Clef -> Bool
@@ -152,8 +152,8 @@ isHistoricalClef _ = False
 
 -- | Is this a traditional voice clef, i.e. a C clef on some staff.
 isVoiceClef :: Clef -> Bool
-isVoiceClef x | x == altoClef    = True
-isVoiceClef x | x == tenorClef   = True
-isVoiceClef x | otherwise        = False
+isVoiceClef x | x == altoClef    = True
+isVoiceClef x | x == tenorClef   = True
+isVoiceClef x | otherwise        = False
 
 
diff --git a/src/Music/Pitch/Common/Harmony.hs b/src/Music/Pitch/Common/Harmony.hs
index 32c4fc8..0d8898d 100644
--- a/src/Music/Pitch/Common/Harmony.hs
+++ b/src/Music/Pitch/Common/Harmony.hs
@@ -21,7 +21,7 @@ import qualified Data.Set as Set
 {-
   TODO
   Generalize simple like this:
-    > (number (asInterval (m9))-(fromIntegral $ signum (m9))) `mod` 7
+    > (number (asInterval (m9))-(fromIntegral $ signum (m9))) `mod` 7
     
 -}
 
diff --git a/src/Music/Pitch/Common/Interval.hs b/src/Music/Pitch/Common/Interval.hs
index d9a283f..6761166 100644
--- a/src/Music/Pitch/Common/Interval.hs
+++ b/src/Music/Pitch/Common/Interval.hs
@@ -145,7 +145,7 @@ instance FromJSON ChromaticSteps where
   parseJSON = fmap fromInteger . parseJSON
 
 instance ToJSON Interval where
-  toJSON i = Data.Aeson.object [("steps", toJSON $ i^._steps), ("alteration", toJSON $ i^._alteration)]
+  toJSON i = Data.Aeson.object [("steps", toJSON $ i^._steps), ("alteration", toJSON $ i^._alteration)]
 
 instance FromJSON Interval where
   parseJSON (Data.Aeson.Object x) = liftA2 (curry (^.interval')) alteration steps
diff --git a/src/Music/Pitch/Common/Names.hs b/src/Music/Pitch/Common/Names.hs
index 779be8d..65b7ed7 100644
--- a/src/Music/Pitch/Common/Names.hs
+++ b/src/Music/Pitch/Common/Names.hs
@@ -42,7 +42,7 @@ showKey :: Language -> Pitch -> Mode -> String
 showKey lang pitch mode = showPitch lang pitch ++ showSep lang ++ showMode lang mode
 
 showPitch :: Language -> Pitch -> String
-showPitch lang pitch = (!! (pitchToIndex + pitchNameOffset)) $ fromMaybe (error "showPitch: Bad lang") $ listToMaybe $ filter (\xs -> head xs == show lang) $ pitchNames
+showPitch lang pitch = (!! (pitchToIndex + pitchNameOffset)) $ fromMaybe (error "showPitch: Bad lang") $ listToMaybe $ filter (\xs -> head xs == show lang) $ pitchNames
   where
     -- TODO normalize dbb etc.
     pitchToIndex = fromMaybe (error "showPitch: Bad pitch") $ Data.List.findIndex (== pitch) 
@@ -56,7 +56,7 @@ showPitch lang pitch = (!! (pitchToIndex + pitchNameOffset)) $ fromMaybe (error
     pitchNameOffset = 3
 
 showMode :: Language -> Mode -> String
-showMode lang mode = (!! (modeToIndex + modeNameOffset)) $ fromMaybe (error "showMode: Bad lang") $ listToMaybe $ filter (\xs -> head xs == show lang) $ modeNames
+showMode lang mode = (!! (modeToIndex + modeNameOffset)) $ fromMaybe (error "showMode: Bad lang") $ listToMaybe $ filter (\xs -> head xs == show lang) $ modeNames
   where
     modeToIndex = fromMaybe (error "showPitch: Bad mode") $ Data.List.findIndex (== mode) 
       [MajorMode,MinorMode]     
diff --git a/src/Music/Pitch/Common/Number.hs b/src/Music/Pitch/Common/Number.hs
index 4cd4a0d..388a687 100644
--- a/src/Music/Pitch/Common/Number.hs
+++ b/src/Music/Pitch/Common/Number.hs
@@ -1,5 +1,5 @@
 
--- | Number component of intervals.
+-- | Number component of intervals.
 module Music.Pitch.Common.Number
 (
         Number,
diff --git a/src/Music/Pitch/Common/Quality.hs b/src/Music/Pitch/Common/Quality.hs
index aedcc36..f247b74 100644
--- a/src/Music/Pitch/Common/Quality.hs
+++ b/src/Music/Pitch/Common/Quality.hs
@@ -105,7 +105,7 @@ invertQuality = go
     go (Diminished n)   = Augmented n
 
 
--- | 
+-- | 
 -- The quality type expected for a given number, i.e. perfect for unisons, fourths,
 -- fifths and their compounds; major/minor for everything else.  
 expectedQualityType :: Number -> QualityType
@@ -127,7 +127,7 @@ qualityTypes _       = [PerfectType, MajorMinorType]
 isValidQualityNumber :: Quality -> Number -> Bool
 isValidQualityNumber q n = expectedQualityType n `elem` qualityTypes q
 
-data Direction = Upward | Downward
+data Direction = Upward | Downward
   deriving (Eq, Ord, Show)
 
 -- |
diff --git a/src/Music/Pitch/Common/Types.hs b/src/Music/Pitch/Common/Types.hs
index f9125f2..fd221ca 100644
--- a/src/Music/Pitch/Common/Types.hs
+++ b/src/Music/Pitch/Common/Types.hs
@@ -83,10 +83,10 @@ Alternatively, we could do it as a recursive type
 
 data Quality
   = Major
-  | Minor
-  | Perfect
+  | Minor
+  | Perfect
   | Augment Quality
-  | Diminish Quality
+  | Diminish Quality
 -}
 
 {-|
diff --git a/src/Music/Pitch/Equal.hs b/src/Music/Pitch/Equal.hs
index 8357ce7..86d44d2 100644
--- a/src/Music/Pitch/Equal.hs
+++ b/src/Music/Pitch/Equal.hs
@@ -48,7 +48,7 @@ import TypeUnary.Nat
 
 -- Based on Data.Fixed
 
-newtype Equal a = Equal { getEqual :: Int }
+newtype Equal a = Equal { getEqual :: Int }
 
 deriving instance Eq (Equal a)
 deriving instance Ord (Equal a)
@@ -104,11 +104,11 @@ size = natToZ . getSize
 -- This type implements limited values (useful for interval *steps*)
 -- An ET-interval is just an int, with a type-level size (divMod is "separate")
 
--- -- | Create an equal-temperament value.
+-- -- | Create an equal-temperament value.
 -- toEqual :: IsNat a => Int -> Maybe (Equal a)
 -- toEqual = checkSize . Equal
 -- 
--- -- | Unsafely create an equal-temperament value.
+-- -- | Unsafely create an equal-temperament value.
 -- unsafeToEqual :: IsNat a => Int -> Equal a
 -- unsafeToEqual n = case toEqual n of
 --   Nothing -> error $ "Bad equal: " ++ show n
@@ -118,7 +118,7 @@ size = natToZ . getSize
 -- checkSize x = if 0 <= fromEqual x && fromEqual x < size x then Just x else Nothing
 -- 
 
--- | Create an equal-temperament value.
+-- | Create an equal-temperament value.
 toEqual :: IsNat a => Int -> Equal a
 toEqual = Equal
 
diff --git a/src/Music/Pitch/Intonation.hs b/src/Music/Pitch/Intonation.hs
index 0ad3be4..e33a774 100644
--- a/src/Music/Pitch/Intonation.hs
+++ b/src/Music/Pitch/Intonation.hs
@@ -112,7 +112,7 @@ thirtyOneToneEqual = tetTune dddd3 where dddd3 = m3 ^-^ (4 *^ _A1)
 fiftyThreeToneEqual :: Tuning Interval
 fiftyThreeToneEqual = tetTune ddddddd6 where ddddddd6 = 31 *^ _P8 ^-^ 53 *^ _P5 -- (!)
 
--- | Modern standard intonation, i.e. 12-TET with @a = 440 Hz@.
+-- | Modern standard intonation, i.e. 12-TET with @a = 440 Hz@.
 standardIntonation :: Intonation Pitch
 standardIntonation = intone (a, 440) twelveToneEqual
 
diff --git a/src/Music/Pitch/Scale.hs b/src/Music/Pitch/Scale.hs
index 5522a3a..9e9929e 100644
--- a/src/Music/Pitch/Scale.hs
+++ b/src/Music/Pitch/Scale.hs
@@ -80,7 +80,7 @@ import Music.Pitch.Literal
 import Music.Pitch.Common hiding (Mode)
 
 
--- | A mode is a list of intervals and a characteristic repeating interval. 
+-- | A mode is a list of intervals and a characteristic repeating interval.
 data Mode a = Mode [Diff a] (Diff a) -- intervals, repeat (usually octave)
 
 -- |
@@ -98,7 +98,7 @@ modeIntervals f (Mode is r) = fmap (\is -> Mode is r) $ f is
 modeRepeat :: Lens' (Mode a) (Diff a)
 modeRepeat f (Mode is r) = fmap (\r -> Mode is r) $ f r
 
--- | A scale is a mode with a specified tonic.
+-- | A scale is a mode with a specified tonic.
 data Scale a = Scale a (Mode a)      -- root, mode
 
 modeToScale :: AffineSpace a => a -> Mode a -> Scale a
@@ -107,12 +107,12 @@ modeToScale = Scale
 -- |
 -- > Lens' (Scale Pitch) Pitch
 scaleTonic :: Lens' (Scale a) a
-scaleTonic f (Scale t xs) = fmap (\t -> Scale t xs) $ f t
+scaleTonic f (Scale t xs) = fmap (\t -> Scale t xs) $ f t
 
 -- |
 -- > Lens' (Scale Pitch) (Mode Pitch)
 scaleMode :: Lens' (Scale a) (Mode a)
-scaleMode f (Scale t xs) = fmap (\xs -> Scale t xs) $ f xs
+scaleMode f (Scale t xs) = fmap (\xs -> Scale t xs) $ f xs
 
 -- |
 --
@@ -168,12 +168,12 @@ functionToChord = Chord
 -- |
 -- > Lens' (Chord Pitch) Pitch
 chordTonic :: Lens' (Chord a) a
-chordTonic f (Chord t xs) = fmap (\t -> Chord t xs) $ f t
+chordTonic f (Chord t xs) = fmap (\t -> Chord t xs) $ f t
 
 -- |
 -- > Lens' (Chord Pitch) (Function Pitch)
 chordFunction :: Lens' (Chord a) (Function a)
-chordFunction f (Chord t xs) = fmap (\xs -> Chord t xs) $ f xs
+chordFunction f (Chord t xs) = fmap (\xs -> Chord t xs) $ f xs
 
 -- |
 --