diff --git a/massiv-io.cabal b/massiv-io.cabal
--- a/massiv-io.cabal
+++ b/massiv-io.cabal
@@ -1,5 +1,5 @@
 name:                massiv-io
-version:             0.1.1.0
+version:             0.1.2.0
 synopsis:            Import/export of Image files into massiv Arrays
 description:         This package contains functionality for import/export of arrays
                      into the real world. For now it only has the ability to read/write
diff --git a/src/Graphics/ColorSpace.hs b/src/Graphics/ColorSpace.hs
--- a/src/Graphics/ColorSpace.hs
+++ b/src/Graphics/ColorSpace.hs
@@ -111,7 +111,7 @@
   X(..),
   -- * Precision
   -- ** Pixel
-  Elevator,
+  Elevator(..),
   toWord8,
   toWord16,
   toWord32,
@@ -270,11 +270,11 @@
 
 
 instance ToRGB X Bit where
-  toPixelRGB (PixelX b) = promote $ eToDouble b
+  toPixelRGB (PixelX b) = pure $ eToDouble b
   {-# INLINE toPixelRGB #-}
 
 instance Elevator e => ToRGB Y e where
-  toPixelRGB (PixelY g) = promote $ eToDouble g
+  toPixelRGB (PixelY g) = pure $ eToDouble g
   {-# INLINE toPixelRGB #-}
 
 instance Elevator e => ToRGB YA e where
diff --git a/src/Graphics/ColorSpace/Binary.hs b/src/Graphics/ColorSpace/Binary.hs
--- a/src/Graphics/ColorSpace/Binary.hs
+++ b/src/Graphics/ColorSpace/Binary.hs
@@ -18,6 +18,7 @@
   Bit(..), on, off, isOn, isOff, fromBool, zero, one, bit2bool, bool2bit, toNum, fromNum
   ) where
 
+import           Control.Applicative
 import           Control.Monad
 import           Data.Bits
 import           Data.Typeable                (Typeable)
@@ -85,21 +86,21 @@
 
 
 instance Bits (Pixel X Bit) where
-  (.&.) = liftPx2 (.&.)
+  (.&.) = liftA2 (.&.)
   {-# INLINE (.&.) #-}
-  (.|.) = liftPx2 (.|.)
+  (.|.) = liftA2 (.|.)
   {-# INLINE (.|.) #-}
-  xor = liftPx2 xor
+  xor = liftA2 xor
   {-# INLINE xor #-}
-  complement = liftPx complement
+  complement = liftA complement
   {-# INLINE complement #-}
-  shift !b !n = liftPx (`shift` n) b
+  shift !b !n = liftA (`shift` n) b
   {-# INLINE shift #-}
-  rotate !b !n = liftPx (`rotate` n) b
+  rotate !b !n = liftA (`rotate` n) b
   {-# INLINE rotate #-}
-  zeroBits = promote zeroBits
+  zeroBits = pure zeroBits
   {-# INLINE zeroBits #-}
-  bit = promote . bit
+  bit = pure . bit
   {-# INLINE bit #-}
   testBit (PixelX (Bit 1)) 0 = True
   testBit _                _ = False
diff --git a/src/Graphics/ColorSpace/CMYK.hs b/src/Graphics/ColorSpace/CMYK.hs
--- a/src/Graphics/ColorSpace/CMYK.hs
+++ b/src/Graphics/ColorSpace/CMYK.hs
@@ -17,7 +17,6 @@
   CMYK(..), CMYKA(..), Pixel(..)
   ) where
 
-import           Control.Applicative
 import           Data.Foldable
 import           Data.Typeable                (Typeable)
 import           Foreign.Ptr
@@ -50,8 +49,6 @@
   {-# INLINE fromComponents #-}
   toComponents (PixelCMYK c m y k) = (c, m, y, k)
   {-# INLINE toComponents #-}
-  promote !e = PixelCMYK e e e e
-  {-# INLINE promote #-}
   getPxC (PixelCMYK c _ _ _) CyanCMYK = c
   getPxC (PixelCMYK _ m _ _) MagCMYK  = m
   getPxC (PixelCMYK _ _ y _) YelCMYK  = y
@@ -65,10 +62,6 @@
   mapPxC f (PixelCMYK c m y k) =
     PixelCMYK (f CyanCMYK c) (f MagCMYK m) (f YelCMYK y) (f KeyCMYK k)
   {-# INLINE mapPxC #-}
-  liftPx = fmap
-  {-# INLINE liftPx #-}
-  liftPx2 = liftA2
-  {-# INLINE liftPx2 #-}
   foldlPx = foldl'
   {-# INLINE foldlPx #-}
   foldlPx2 f !z (PixelCMYK c1 m1 y1 k1) (PixelCMYK c2 m2 y2 k2) =
@@ -144,8 +137,6 @@
   {-# INLINE fromComponents #-}
   toComponents (PixelCMYKA c m y k a) = (c, m, y, k, a)
   {-# INLINE toComponents #-}
-  promote !e = PixelCMYKA e e e e e
-  {-# INLINE promote #-}
   getPxC (PixelCMYKA c _ _ _ _) CyanCMYKA  = c
   getPxC (PixelCMYKA _ m _ _ _) MagCMYKA   = m
   getPxC (PixelCMYKA _ _ y _ _) YelCMYKA   = y
@@ -161,12 +152,6 @@
   mapPxC f (PixelCMYKA c m y k a) =
     PixelCMYKA (f CyanCMYKA c) (f MagCMYKA m) (f YelCMYKA y) (f KeyCMYKA k) (f AlphaCMYKA a)
   {-# INLINE mapPxC #-}
-  liftPx = fmap
-  {-# INLINE liftPx #-}
-  liftPx2 = liftA2
-  {-# INLINE liftPx2 #-}
-  foldlPx = foldl'
-  {-# INLINE foldlPx #-}
   foldlPx2 f !z (PixelCMYKA c1 m1 y1 k1 a1) (PixelCMYKA c2 m2 y2 k2 a2) =
     f (f (f (f (f z c1 c2) m1 m2) y1 y2) k1 k2) a1 a2
   {-# INLINE foldlPx2 #-}
diff --git a/src/Graphics/ColorSpace/Complex.hs b/src/Graphics/ColorSpace/Complex.hs
--- a/src/Graphics/ColorSpace/Complex.hs
+++ b/src/Graphics/ColorSpace/Complex.hs
@@ -6,7 +6,7 @@
 #endif
 -- |
 -- Module      : Graphics.ColorSpace.Complex
--- Copyright   : (c) Alexey Kuleshevich 2016
+-- Copyright   : (c) Alexey Kuleshevich 2016-2018
 -- License     : BSD3
 -- Maintainer  : Alexey Kuleshevich <lehins@yandex.ru>
 -- Stability   : experimental
@@ -34,51 +34,51 @@
 --
 -- @ PixelRGB 4 8 6 '+:' PixelRGB 7 1 1 __==__ PixelRGB (4 ':+' 7) (8 ':+' 1) (6 ':+' 1) @
 --
-(+:) :: Applicative (Pixel cs) => Pixel cs e -> Pixel cs e -> Pixel cs (Complex e)
+(+:) :: ColorSpace cs e => Pixel cs e -> Pixel cs e -> Pixel cs (Complex e)
 (+:) = liftA2 (:+)
 {-# INLINE (+:) #-}
 
 -- | Extracts the real part of a complex pixel.
-realPart :: (Applicative (Pixel cs), RealFloat e) => Pixel cs (Complex e) -> Pixel cs e
+realPart :: (ColorSpace cs e, RealFloat e) => Pixel cs (Complex e) -> Pixel cs e
 realPart = liftA C.realPart
 {-# INLINE realPart #-}
 
 -- | Extracts the imaginary part of a complex pixel.
-imagPart :: (Applicative (Pixel cs), RealFloat e) => Pixel cs (Complex e) -> Pixel cs e
+imagPart :: (ColorSpace cs e, RealFloat e) => Pixel cs (Complex e) -> Pixel cs e
 imagPart = liftA C.imagPart
 {-# INLINE imagPart #-}
 
 -- | Form a complex pixel from polar components of magnitude and phase.
-mkPolar :: (Applicative (Pixel cs), RealFloat e) =>
+mkPolar :: (ColorSpace cs e, RealFloat e) =>
            Pixel cs e -> Pixel cs e -> Pixel cs (Complex e)
 mkPolar = liftA2 C.mkPolar
 {-# INLINE mkPolar #-}
 
 -- | @'cis' t@ is a complex pixel with magnitude 1 and phase t (modulo @2*'pi'@).
-cis :: (Applicative (Pixel cs), RealFloat e) => Pixel cs e -> Pixel cs (Complex e)
+cis :: (ColorSpace cs e, RealFloat e) => Pixel cs e -> Pixel cs (Complex e)
 cis = liftA C.cis
 {-# INLINE cis #-}
 
 -- | The function @'polar'@ takes a complex pixel and returns a (magnitude, phase)
 -- pair of pixels in canonical form: the magnitude is nonnegative, and the phase
 -- in the range @(-'pi', 'pi']@; if the magnitude is zero, then so is the phase.
-polar :: (Applicative (Pixel cs), RealFloat e) => Pixel cs (Complex e) -> (Pixel cs e, Pixel cs e)
+polar :: (ColorSpace cs e, RealFloat e) => Pixel cs (Complex e) -> (Pixel cs e, Pixel cs e)
 polar !zPx = (magnitude zPx, phase zPx)
 {-# INLINE polar #-}
 
 -- | The nonnegative magnitude of a complex pixel.
-magnitude :: (Applicative (Pixel cs), RealFloat e) => Pixel cs (Complex e) -> Pixel cs e
+magnitude :: (ColorSpace cs e, RealFloat e) => Pixel cs (Complex e) -> Pixel cs e
 magnitude = liftA C.magnitude
 {-# INLINE magnitude #-}
 
 -- | The phase of a complex pixel, in the range @(-'pi', 'pi']@. If the
 -- magnitude is zero, then so is the phase.
-phase :: (Applicative (Pixel cs), RealFloat e) => Pixel cs (Complex e) -> Pixel cs e
+phase :: (ColorSpace cs e, RealFloat e) => Pixel cs (Complex e) -> Pixel cs e
 phase = liftA C.phase
 {-# INLINE phase #-}
 
 -- | The conjugate of a complex pixel.
-conjugate :: (Applicative (Pixel cs), RealFloat e) => Pixel cs (Complex e) -> Pixel cs (Complex e)
+conjugate :: (ColorSpace cs e, RealFloat e) => Pixel cs (Complex e) -> Pixel cs (Complex e)
 conjugate = liftA C.conjugate
 {-# INLINE conjugate #-}
 
diff --git a/src/Graphics/ColorSpace/HSI.hs b/src/Graphics/ColorSpace/HSI.hs
--- a/src/Graphics/ColorSpace/HSI.hs
+++ b/src/Graphics/ColorSpace/HSI.hs
@@ -17,7 +17,6 @@
   HSI(..), HSIA(..), Pixel(..)
   ) where
 
-import           Control.Applicative
 import           Data.Foldable
 import           Data.Typeable                (Typeable)
 import           Foreign.Ptr
@@ -49,8 +48,6 @@
   {-# INLINE toComponents #-}
   fromComponents !(h, s, i) = PixelHSI h s i
   {-# INLINE fromComponents #-}
-  promote = pure
-  {-# INLINE promote #-}
   getPxC (PixelHSI h _ _) HueHSI = h
   getPxC (PixelHSI _ s _) SatHSI = s
   getPxC (PixelHSI _ _ i) IntHSI = i
@@ -61,10 +58,6 @@
   {-# INLINE setPxC #-}
   mapPxC f (PixelHSI h s i) = PixelHSI (f HueHSI h) (f SatHSI s) (f IntHSI i)
   {-# INLINE mapPxC #-}
-  liftPx = fmap
-  {-# INLINE liftPx #-}
-  liftPx2 = liftA2
-  {-# INLINE liftPx2 #-}
   foldlPx = foldl'
   {-# INLINE foldlPx #-}
   foldlPx2 f !z (PixelHSI h1 s1 i1) (PixelHSI h2 s2 i2) =
@@ -135,8 +128,6 @@
   {-# INLINE toComponents #-}
   fromComponents !(h, s, i, a) = PixelHSIA h s i a
   {-# INLINE fromComponents #-}
-  promote = pure
-  {-# INLINE promote #-}
   getPxC (PixelHSIA h _ _ _) HueHSIA   = h
   getPxC (PixelHSIA _ s _ _) SatHSIA   = s
   getPxC (PixelHSIA _ _ i _) IntHSIA   = i
@@ -150,12 +141,6 @@
   mapPxC f (PixelHSIA h s i a) =
     PixelHSIA (f HueHSIA h) (f SatHSIA s) (f IntHSIA i) (f AlphaHSIA a)
   {-# INLINE mapPxC #-}
-  liftPx = fmap
-  {-# INLINE liftPx #-}
-  liftPx2 = liftA2
-  {-# INLINE liftPx2 #-}
-  foldlPx = foldl'
-  {-# INLINE foldlPx #-}
   foldlPx2 f !z (PixelHSIA h1 s1 i1 a1) (PixelHSIA h2 s2 i2 a2) =
     f (f (f (f z h1 h2) s1 s2) i1 i2) a1 a2
   {-# INLINE foldlPx2 #-}
diff --git a/src/Graphics/ColorSpace/Internal.hs b/src/Graphics/ColorSpace/Internal.hs
--- a/src/Graphics/ColorSpace/Internal.hs
+++ b/src/Graphics/ColorSpace/Internal.hs
@@ -18,11 +18,11 @@
   , module Graphics.ColorSpace.Elevator
   ) where
 
+import           Control.Applicative
 import           Control.DeepSeq              (NFData (rnf), deepseq)
 import           Control.Monad                (liftM)
 import           Data.Default
 import           Data.Foldable
-import           Data.Maybe                   (fromMaybe)
 import           Data.Typeable
 import qualified Data.Vector.Generic          as V
 import qualified Data.Vector.Generic.Mutable  as VM
@@ -36,7 +36,8 @@
 
 
 class (Eq cs, Enum cs, Show cs, Bounded cs, Typeable cs,
-      Eq (Pixel cs e), VU.Unbox (Components cs e), VS.Storable (Pixel cs e), Elevator e)
+       Functor (Pixel cs), Applicative (Pixel cs), Foldable (Pixel cs),
+       Eq (Pixel cs e), VU.Unbox (Components cs e), VS.Storable (Pixel cs e), Elevator e)
       => ColorSpace cs e where
 
   type Components cs e
@@ -50,6 +51,8 @@
 
   -- | Construt a Pixel by replicating the same value across all of the components.
   promote :: e -> Pixel cs e
+  promote = pure
+  {-# INLINE promote #-}
 
   -- | Retrieve Pixel's component value
   getPxC :: Pixel cs e -> cs -> e
@@ -60,36 +63,40 @@
   -- | Map a channel aware function over all Pixel's components.
   mapPxC :: (cs -> e -> e) -> Pixel cs e -> Pixel cs e
 
+  -- | Left fold on two pixels a the same time. If accumulator is nutrual to the folding funciton
+  -- then it's equivalent to @foldlPx2 f acc px1 px2 == foldl' acc (liftA2 (f acc) px1 px2)@
+  foldlPx2 :: (b -> e -> e -> b) -> b -> Pixel cs e -> Pixel cs e -> b
+
   -- | Map a function over all Pixel's componenets.
   liftPx :: (e -> e) -> Pixel cs e -> Pixel cs e
+  liftPx = fmap
+  {-# INLINE liftPx #-}
 
   -- | Zip two Pixels with a function.
   liftPx2 :: (e -> e -> e) -> Pixel cs e -> Pixel cs e -> Pixel cs e
-
-  -- | Left fold on two pixels a the same time.
-  foldlPx2 :: (b -> e -> e -> b) -> b -> Pixel cs e -> Pixel cs e -> b
+  liftPx2 = liftA2
+  {-# INLINE liftPx2 #-}
 
   -- | Right fold over all Pixel's components.
   foldrPx :: (e -> b -> b) -> b -> Pixel cs e -> b
-  foldrPx f !z0 !xs = foldlPx f' id xs z0
-      where f' k x !z = k $! f x z
+  foldrPx = foldr'
+  {-# INLINE foldrPx #-}
 
   -- | Left strict fold over all Pixel's components.
   foldlPx :: (b -> e -> b) -> b -> Pixel cs e -> b
-  foldlPx f !z0 !xs = foldrPx f' id xs z0
-      where f' x k !z = k $! f z x
+  foldlPx = foldl'
+  {-# INLINE foldlPx #-}
 
   foldl1Px :: (e -> e -> e) -> Pixel cs e -> e
-  foldl1Px f !xs = fromMaybe (error "foldl1Px: empty Pixel")
-                  (foldlPx mf Nothing xs)
-      where
-        mf m !y = Just (case m of
-                           Nothing -> y
-                           Just x  -> f x y)
-  toListPx :: Pixel cs e -> [e]
-  toListPx !px = foldr' f [] (enumFrom (toEnum 0))
-    where f !cs !ls = getPxC px cs:ls
+  foldl1Px = foldl1
+  {-# INLINE foldl1Px #-}
 
+{-# DEPRECATED liftPx "Use `fmap` from `Functor` instead" #-}
+{-# DEPRECATED liftPx2 "Use `liftA2` from `Applicative` instead" #-}
+{-# DEPRECATED promote "Use `pure` from `Applicative` instead" #-}
+{-# DEPRECATED foldlPx "Use `foldl'` from `Foldable` instead" #-}
+{-# DEPRECATED foldrPx "Use `foldr'` from `Foldable` instead" #-}
+{-# DEPRECATED foldl1Px "Use `foldl1` from `Foldable` instead" #-}
 
 -- | A color space that supports transparency.
 class (ColorSpace (Opaque cs) e, ColorSpace cs e) => AlphaSpace cs e where
@@ -118,24 +125,24 @@
 
 
 instance ColorSpace cs e => Num (Pixel cs e) where
-  (+)         = liftPx2 (+)
+  (+)         = liftA2 (+)
   {-# INLINE (+) #-}
-  (-)         = liftPx2 (-)
+  (-)         = liftA2 (-)
   {-# INLINE (-) #-}
-  (*)         = liftPx2 (*)
+  (*)         = liftA2 (*)
   {-# INLINE (*) #-}
-  abs         = liftPx abs
+  abs         = liftA abs
   {-# INLINE abs #-}
-  signum      = liftPx signum
+  signum      = liftA signum
   {-# INLINE signum #-}
   fromInteger = promote . fromInteger
   {-# INLINE fromInteger #-}
 
 
 instance (ColorSpace cs e, Fractional e) => Fractional (Pixel cs e) where
-  (/)          = liftPx2 (/)
+  (/)          = liftA2 (/)
   {-# INLINE (/) #-}
-  recip        = liftPx recip
+  recip        = liftA recip
   {-# INLINE recip #-}
   fromRational = promote . fromRational
   {-# INLINE fromRational #-}
@@ -144,29 +151,29 @@
 instance (ColorSpace cs e, Floating e) => Floating (Pixel cs e) where
   pi      = promote pi
   {-# INLINE pi #-}
-  exp     = liftPx exp
+  exp     = liftA exp
   {-# INLINE exp #-}
-  log     = liftPx log
+  log     = liftA log
   {-# INLINE log #-}
-  sin     = liftPx sin
+  sin     = liftA sin
   {-# INLINE sin #-}
-  cos     = liftPx cos
+  cos     = liftA cos
   {-# INLINE cos #-}
-  asin    = liftPx asin
+  asin    = liftA asin
   {-# INLINE asin #-}
-  atan    = liftPx atan
+  atan    = liftA atan
   {-# INLINE atan #-}
-  acos    = liftPx acos
+  acos    = liftA acos
   {-# INLINE acos #-}
-  sinh    = liftPx sinh
+  sinh    = liftA sinh
   {-# INLINE sinh #-}
-  cosh    = liftPx cosh
+  cosh    = liftA cosh
   {-# INLINE cosh #-}
-  asinh   = liftPx asinh
+  asinh   = liftA asinh
   {-# INLINE asinh #-}
-  atanh   = liftPx atanh
+  atanh   = liftA atanh
   {-# INLINE atanh #-}
-  acosh   = liftPx acosh
+  acosh   = liftA acosh
   {-# INLINE acosh #-}
 
 instance (ColorSpace cs e, Bounded e) => Bounded (Pixel cs e) where
@@ -177,7 +184,7 @@
 
 instance (ColorSpace cs e, NFData e) => NFData (Pixel cs e) where
 
-  rnf = foldrPx deepseq ()
+  rnf = foldr' deepseq ()
   {-# INLINE rnf #-}
 
 
diff --git a/src/Graphics/ColorSpace/RGB.hs b/src/Graphics/ColorSpace/RGB.hs
--- a/src/Graphics/ColorSpace/RGB.hs
+++ b/src/Graphics/ColorSpace/RGB.hs
@@ -18,10 +18,8 @@
   ) where
 
 import Prelude hiding (map)
-import Control.Applicative
 import Foreign.Ptr
 import Foreign.Storable
-import Data.Foldable
 import Data.Typeable (Typeable)
 import Graphics.ColorSpace.Internal
 
@@ -48,8 +46,6 @@
   {-# INLINE toComponents #-}
   fromComponents !(r, g, b) = PixelRGB r g b
   {-# INLINE fromComponents #-}
-  promote = pure
-  {-# INLINE promote #-}
   getPxC (PixelRGB r _ _) RedRGB   = r
   getPxC (PixelRGB _ g _) GreenRGB = g
   getPxC (PixelRGB _ _ b) BlueRGB  = b
@@ -60,12 +56,6 @@
   {-# INLINE setPxC #-}
   mapPxC f (PixelRGB r g b) = PixelRGB (f RedRGB r) (f GreenRGB g) (f BlueRGB b)
   {-# INLINE mapPxC #-}
-  liftPx = fmap
-  {-# INLINE liftPx #-}
-  liftPx2 = liftA2
-  {-# INLINE liftPx2 #-}
-  foldlPx = foldl'
-  {-# INLINE foldlPx #-}
   foldlPx2 f !z (PixelRGB r1 g1 b1) (PixelRGB r2 g2 b2) =
     f (f (f z r1 r2) g1 g2) b1 b2
   {-# INLINE foldlPx2 #-}
@@ -129,8 +119,6 @@
   {-# INLINE toComponents #-}
   fromComponents !(r, g, b, a) = PixelRGBA r g b a
   {-# INLINE fromComponents #-}
-  promote = pure
-  {-# INLINE promote #-}
   getPxC (PixelRGBA r _ _ _) RedRGBA   = r
   getPxC (PixelRGBA _ g _ _) GreenRGBA = g
   getPxC (PixelRGBA _ _ b _) BlueRGBA  = b
@@ -144,12 +132,6 @@
   mapPxC f (PixelRGBA r g b a) =
     PixelRGBA (f RedRGBA r) (f GreenRGBA g) (f BlueRGBA b) (f AlphaRGBA a)
   {-# INLINE mapPxC #-}
-  liftPx = fmap
-  {-# INLINE liftPx #-}
-  liftPx2 = liftA2
-  {-# INLINE liftPx2 #-}
-  foldlPx = foldl'
-  {-# INLINE foldlPx #-}
   foldlPx2 f !z (PixelRGBA r1 g1 b1 a1) (PixelRGBA r2 g2 b2 a2) =
     f (f (f (f z r1 r2) g1 g2) b1 b2) a1 a2
   {-# INLINE foldlPx2 #-}
diff --git a/src/Graphics/ColorSpace/X.hs b/src/Graphics/ColorSpace/X.hs
--- a/src/Graphics/ColorSpace/X.hs
+++ b/src/Graphics/ColorSpace/X.hs
@@ -20,7 +20,6 @@
   , fromPixelsX
   ) where
 
-import           Control.Applicative
 import           Data.Foldable
 import           Data.Typeable                (Typeable)
 import           Foreign.Ptr
@@ -46,8 +45,6 @@
 instance Elevator e => ColorSpace X e where
   type Components X e = e
 
-  promote = PixelX
-  {-# INLINE promote #-}
   fromComponents = PixelX
   {-# INLINE fromComponents #-}
   toComponents (PixelX g) = g
@@ -58,12 +55,6 @@
   {-# INLINE setPxC #-}
   mapPxC f (PixelX g) = PixelX (f X g)
   {-# INLINE mapPxC #-}
-  liftPx = fmap
-  {-# INLINE liftPx #-}
-  liftPx2 = liftA2
-  {-# INLINE liftPx2 #-}
-  foldlPx = foldl'
-  {-# INLINE foldlPx #-}
   foldlPx2 f !z (PixelX g1) (PixelX g2) = f z g1 g2
   {-# INLINE foldlPx2 #-}
 
@@ -118,7 +109,7 @@
 -- [<X:(4)>,<X:(5)>,<X:(6)>]
 --
 toPixelsX :: ColorSpace cs e => Pixel cs e -> [Pixel X e]
-toPixelsX = foldrPx ((:) . PixelX) []
+toPixelsX = fmap PixelX . toList
 
 -- | Combine a list of `X` pixels into a Pixel with a specified channel
 -- order. Not the most efficient way to construct a pixel, but might prove
@@ -130,7 +121,7 @@
 -- <RGB:(4.0|5.0|6.0)>
 --
 fromPixelsX :: ColorSpace cs e => [(cs, Pixel X e)] -> Pixel cs e
-fromPixelsX = foldl' f (promote 0) where
+fromPixelsX = foldl' f (pure 0) where
   f !px (c, PixelX x) = setPxC px c x
 
 
diff --git a/src/Graphics/ColorSpace/Y.hs b/src/Graphics/ColorSpace/Y.hs
--- a/src/Graphics/ColorSpace/Y.hs
+++ b/src/Graphics/ColorSpace/Y.hs
@@ -17,7 +17,6 @@
   Y(..), YA(..), Pixel(..)
   ) where
 
-import           Control.Applicative
 import           Data.Foldable
 import           Data.Typeable                (Typeable)
 import           Foreign.Ptr
@@ -40,8 +39,6 @@
 
 instance Elevator e => ColorSpace Y e where
   type Components Y e = e
-  promote = PixelY
-  {-# INLINE promote #-}
   fromComponents = PixelY
   {-# INLINE fromComponents #-}
   toComponents (PixelY y) = y
@@ -52,12 +49,6 @@
   {-# INLINE setPxC #-}
   mapPxC f (PixelY y) = PixelY (f LumaY y)
   {-# INLINE mapPxC #-}
-  liftPx = fmap
-  {-# INLINE liftPx #-}
-  liftPx2 = liftA2
-  {-# INLINE liftPx2 #-}
-  foldlPx = foldl'
-  {-# INLINE foldlPx #-}
   foldlPx2 f !z (PixelY y1) (PixelY y2) = f z y1 y2
   {-# INLINE foldlPx2 #-}
 
@@ -124,8 +115,6 @@
 
 instance Elevator e => ColorSpace YA e where
   type Components YA e = (e, e)
-  promote e = PixelYA e e
-  {-# INLINE promote #-}
   fromComponents (y, a) = PixelYA y a
   {-# INLINE fromComponents #-}
   toComponents (PixelYA y a) = (y, a)
@@ -138,12 +127,6 @@
   {-# INLINE setPxC #-}
   mapPxC f (PixelYA y a) = PixelYA (f LumaYA y) (f AlphaYA a)
   {-# INLINE mapPxC #-}
-  liftPx = fmap
-  {-# INLINE liftPx #-}
-  liftPx2 = liftA2
-  {-# INLINE liftPx2 #-}
-  foldlPx = foldl'
-  {-# INLINE foldlPx #-}
   foldlPx2 f !z (PixelYA y1 a1) (PixelYA y2 a2) = f (f z y1 y2) a1 a2
   {-# INLINE foldlPx2 #-}
 
diff --git a/src/Graphics/ColorSpace/YCbCr.hs b/src/Graphics/ColorSpace/YCbCr.hs
--- a/src/Graphics/ColorSpace/YCbCr.hs
+++ b/src/Graphics/ColorSpace/YCbCr.hs
@@ -17,7 +17,6 @@
   YCbCr(..), YCbCrA(..), Pixel(..)
   ) where
 
-import           Control.Applicative
 import           Data.Foldable
 import           Data.Typeable            (Typeable)
 import           Foreign.Ptr
@@ -46,8 +45,6 @@
 instance Elevator e => ColorSpace YCbCr e where
   type Components YCbCr e = (e, e, e)
 
-  promote !e = PixelYCbCr e e e
-  {-# INLINE promote #-}
   fromComponents !(y, b, r) = PixelYCbCr y b r
   {-# INLINE fromComponents #-}
   toComponents (PixelYCbCr y b r) = (y, b, r)
@@ -62,12 +59,6 @@
   {-# INLINE setPxC #-}
   mapPxC f (PixelYCbCr y b r) = PixelYCbCr (f LumaYCbCr y) (f CBlueYCbCr b) (f CRedYCbCr r)
   {-# INLINE mapPxC #-}
-  liftPx = fmap
-  {-# INLINE liftPx #-}
-  liftPx2 = liftA2
-  {-# INLINE liftPx2 #-}
-  foldlPx = foldl'
-  {-# INLINE foldlPx #-}
   foldlPx2 f !z (PixelYCbCr y1 b1 r1) (PixelYCbCr y2 b2 r2) =
     f (f (f z y1 y2) b1 b2) r1 r2
   {-# INLINE foldlPx2 #-}
@@ -133,8 +124,6 @@
 instance Elevator e => ColorSpace YCbCrA e where
   type Components YCbCrA e = (e, e, e, e)
 
-  promote !e = PixelYCbCrA e e e e
-  {-# INLINE promote #-}
   fromComponents !(y, b, r, a) = PixelYCbCrA y b r a
   {-# INLINE fromComponents #-}
   toComponents (PixelYCbCrA y b r a) = (y, b, r, a)
@@ -152,12 +141,6 @@
   mapPxC f (PixelYCbCrA y b r a) =
     PixelYCbCrA (f LumaYCbCrA y) (f CBlueYCbCrA b) (f CRedYCbCrA r) (f AlphaYCbCrA a)
   {-# INLINE mapPxC #-}
-  liftPx = fmap
-  {-# INLINE liftPx #-}
-  liftPx2 = liftA2
-  {-# INLINE liftPx2 #-}
-  foldlPx = foldl'
-  {-# INLINE foldlPx #-}
   foldlPx2 f !z (PixelYCbCrA y1 b1 r1 a1) (PixelYCbCrA y2 b2 r2 a2) =
     f (f (f (f z y1 y2) b1 b2) r1 r2) a1 a2
   {-# INLINE foldlPx2 #-}