diff --git a/changelog.md b/changelog.md
--- a/changelog.md
+++ b/changelog.md
@@ -1,3 +1,7 @@
+0.0.4
+
+* Use classy lens/prism
+
 0.0.3
 
 * Remove `Combinators` module
diff --git a/national-australia-bank.cabal b/national-australia-bank.cabal
--- a/national-australia-bank.cabal
+++ b/national-australia-bank.cabal
@@ -1,5 +1,5 @@
 name:                 national-australia-bank
-version:              0.0.3
+version:              0.0.4
 synopsis:             Functions for National Australia Bank transactions
 description:          Parsing, Processing and other functions for National Australia Bank transactions
 license:              BSD3
diff --git a/src/Data/Bank/NationalAustraliaBank/NationalAustraliaBank.hs b/src/Data/Bank/NationalAustraliaBank/NationalAustraliaBank.hs
--- a/src/Data/Bank/NationalAustraliaBank/NationalAustraliaBank.hs
+++ b/src/Data/Bank/NationalAustraliaBank/NationalAustraliaBank.hs
@@ -1,16 +1,11 @@
 {-# OPTIONS_GHC -Wall #-}
-{-# LANGUAGE TemplateHaskell #-}
 {-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE LambdaCase #-}
 
 module Data.Bank.NationalAustraliaBank.NationalAustraliaBank where
 
 import Control.Applicative (Alternative((<|>)))
-import Control.Category (Category(..) )
-import Control.Lens
-    ( view,
-      makePrisms,
-      (#),
-      makeLenses )
+import Control.Lens( Lens', Prism', prism', (#), view )
 import Control.Monad.IO.Class ( MonadIO(..) )
 import Control.Monad.Reader.Class ( MonadReader )
 import Control.Monad.Trans.Except ( ExceptT(..) )
@@ -56,9 +51,8 @@
       try,
       ParsecT,
       Stream )
-import Prelude hiding (id, (.) )
 
-data TransactionMonth =
+data Month =
   Jan
   | Feb
   | Mar
@@ -73,12 +67,158 @@
   | Dec
   deriving (Eq, Ord, Show)
 
-makePrisms ''TransactionMonth
+class HasMonth a where
+  month ::
+    Lens' a Month
 
-parseTransactionMonth ::
+instance HasMonth Month where
+  month =
+    id
+
+class AsMonth a where
+  _Month ::
+    Prism' a Month
+  _Jan ::
+    Prism' a ()
+  _Jan =
+    _Month .
+      prism'
+        (\() -> Jan)
+        (\case
+            Jan ->
+              Just ()
+            _ ->
+              Nothing)
+  _Feb ::
+    Prism' a ()
+  _Feb =
+    _Month .
+      prism'
+        (\() -> Feb)
+        (\case
+            Feb ->
+              Just ()
+            _ ->
+              Nothing)
+  _Mar ::
+    Prism' a ()
+  _Mar =
+    _Month .
+      prism'
+        (\() -> Mar)
+        (\case
+            Mar ->
+              Just ()
+            _ ->
+              Nothing)
+  _Apr ::
+    Prism' a ()
+  _Apr =
+    _Month .
+      prism'
+        (\() -> Apr)
+        (\case
+            Apr ->
+              Just ()
+            _ ->
+              Nothing)
+  _May ::
+    Prism' a ()
+  _May =
+    _Month .
+      prism'
+        (\() -> May)
+        (\case
+            May ->
+              Just ()
+            _ ->
+              Nothing)
+  _Jun ::
+    Prism' a ()
+  _Jun =
+    _Month .
+      prism'
+        (\() -> Jun)
+        (\case
+            Jun ->
+              Just ()
+            _ ->
+              Nothing)
+  _Jul ::
+    Prism' a ()
+  _Jul =
+    _Month .
+      prism'
+        (\() -> Jul)
+        (\case
+            Jul ->
+              Just ()
+            _ ->
+              Nothing)
+  _Aug ::
+    Prism' a ()
+  _Aug =
+    _Month .
+      prism'
+        (\() -> Aug)
+        (\case
+            Aug ->
+              Just ()
+            _ ->
+              Nothing)
+  _Sep ::
+    Prism' a ()
+  _Sep =
+    _Month .
+      prism'
+        (\() -> Sep)
+        (\case
+            Sep ->
+              Just ()
+            _ ->
+              Nothing)
+  _Oct ::
+    Prism' a ()
+  _Oct =
+    _Month .
+      prism'
+        (\() -> Oct)
+        (\case
+            Oct ->
+              Just ()
+            _ ->
+              Nothing)
+  _Nov ::
+    Prism' a ()
+  _Nov =
+    _Month .
+      prism'
+        (\() -> Nov)
+        (\case
+            Nov ->
+              Just ()
+            _ ->
+              Nothing)
+  _Dec ::
+    Prism' a ()
+  _Dec =
+    _Month .
+      prism'
+        (\() -> Dec)
+        (\case
+            Dec ->
+              Just ()
+            _ ->
+              Nothing)
+
+instance AsMonth Month where
+  _Month =
+    id
+
+parseMonth ::
   Stream s m Char =>
-  ParsecT s u m TransactionMonth
-parseTransactionMonth =
+  ParsecT s u m Month
+parseMonth =
   asum . fmap try $ [
     Jan <$ string "Jan"
   , Feb <$ string "Feb"
@@ -94,24 +234,62 @@
   , Dec <$ string "Dec"
   ]
 
-data TransactionDate =
-  TransactionDate {
+data Date =
+  Date {
     _day1 ::
       DecDigit
   , _day2 ::
       DecDigit
   , _month ::
-    TransactionMonth
+    Month
   , _year1 ::
     DecDigit
   , _year2 ::
     DecDigit
   } deriving (Eq, Show)
 
-makeLenses ''TransactionDate
+class HasDate a where
+  date ::
+    Lens' a Date
+  day1 ::
+    Lens' a DecDigit
+  day1 =
+    date .
+    \f (Date d1 d2 m y1 y2) -> fmap (\d1' -> Date d1' d2 m y1 y2) (f d1)
+  day2 ::
+    Lens' a DecDigit
+  day2 =
+    date .
+    \f (Date d1 d2 m y1 y2) -> fmap (\d2' -> Date d1 d2' m y1 y2) (f d2)
+  year1 ::
+    Lens' a DecDigit
+  year1 =
+    date .
+    \f (Date d1 d2 m y1 y2) -> fmap (\y1' -> Date d1 d2 m y1' y2) (f y1)
+  year2 ::
+    Lens' a DecDigit
+  year2 =
+    date .
+    \f (Date d1 d2 m y1 y2) -> fmap (\y2' -> Date d1 d2 m y1 y2') (f y2)
 
-instance Ord TransactionDate where
-  TransactionDate d1 d2 m y1 y2 `compare` TransactionDate e1 e2 n z1 z2 =
+instance HasDate Date where
+  date =
+    id
+
+instance HasMonth Date where
+  month f (Date d1 d2 m y1 y2) =
+    fmap (\m' -> Date d1 d2 m' y1 y2) (f m)
+
+class AsDate a where
+  _Date ::
+    Prism' a Date
+
+instance AsDate Date where
+  _Date =
+    id
+
+instance Ord Date where
+  Date d1 d2 m y1 y2 `compare` Date e1 e2 n z1 z2 =
     let twoDigits a b = decDigitsIntegral (Right (a :| [b]))
         d = twoDigits d1 d2 :: Int
         e = twoDigits e1 e2 :: Int
@@ -119,34 +297,34 @@
         z = twoDigits z1 z2 :: Int
     in  (y, m, d) `compare` (z, n, e)
 
-parseTransactionDate ::
+parseDate ::
   Stream s Identity Char =>
-  ParsecT s u Identity TransactionDate
-parseTransactionDate =
-  TransactionDate <$>
+  ParsecT s u Identity Date
+parseDate =
+  Date <$>
     parseDecimal <*>
     parseDecimal <*
     char ' ' <*>
-    parseTransactionMonth <*
+    parseMonth <*
     char ' ' <*>
     parseDecimal <*>
     parseDecimal
 
-decodeTransactionDate ::
-  Decode' ByteString TransactionDate
-decodeTransactionDate =
-  D.withParsec parseTransactionDate
+decodeDate ::
+  Decode' ByteString Date
+decodeDate =
+  D.withParsec parseDate
 
-encodeTransactionDate ::
-  NameEncode TransactionDate
-encodeTransactionDate =
-  fromString "Date" =: E.mkEncodeBS (\(TransactionDate d1 d2 m y1 y2) ->
+encodeDate ::
+  NameEncode Date
+encodeDate =
+  fromString "Date" =: E.mkEncodeBS (\(Date d1 d2 m y1 y2) ->
     L.fromString (concat [[charDecimal # d1, charDecimal # d2, ' '], show m, [' ', charDecimal # y1], [charDecimal # y2]]))
 
-transactionDayDate ::
+dayDate ::
   Day
-  -> TransactionDate
-transactionDayDate day =
+  -> Date
+dayDate day =
   let (y, m, d) = toGregorian day
       twodigits x =
         case either id id (integralDecDigits x) of
@@ -169,12 +347,12 @@
             11 -> Nov
             _ -> Dec
       (y1, y2) = twodigits (y - 2000)
-  in  TransactionDate d1 d2 m' y1 y2
+  in  Date d1 d2 m' y1 y2
 
-transactionDateDay ::
-  TransactionDate
+dateDay ::
+  Date
   -> Day
-transactionDateDay (TransactionDate d1 d2 m y1 y2) =
+dateDay (Date d1 d2 m y1 y2) =
   let year = 2000 + integralDecimal # y1 * 10 + integralDecimal # y2
       mon Jan = 1
       mon Feb = 2
@@ -191,8 +369,8 @@
       dt = integralDecimal # d1 * 10 + integralDecimal # d2
   in  fromGregorian year (mon m) dt
 
-data TransactionAmount =
-  TransactionAmount {
+data Amount =
+  Amount {
     _negated ::
       Bool
   , _dollars ::
@@ -203,36 +381,70 @@
       DecDigit
   } deriving (Eq, Ord, Show)
 
-makeLenses ''TransactionAmount
+class AsAmount a where
+  _Amount ::
+    Prism' a Amount
 
-parseTransactionAmount ::
+instance AsAmount Amount where
+  _Amount =
+    id
+
+class HasAmount a where
+  amount ::
+    Lens' a Amount
+  negated ::
+    Lens' a Bool
+  negated =
+    amount .
+    \f (Amount n d c1 c2) -> fmap (\n' -> Amount n' d c1 c2) (f n)
+  dollars ::
+    Lens' a (NonEmpty DecDigit)
+  dollars =
+    amount .
+    \f (Amount n d c1 c2) -> fmap (\d' -> Amount n d' c1 c2) (f d)
+  cents1 ::
+    Lens' a DecDigit
+  cents1 =
+    amount .
+    \f (Amount n d c1 c2) -> fmap (\c1' -> Amount n d c1' c2) (f c1)
+  cents2 ::
+    Lens' a DecDigit
+  cents2 =
+    amount .
+    \f (Amount n d c1 c2) -> fmap (\c2' -> Amount n d c1 c2') (f c2)
+
+instance HasAmount Amount where
+  amount =
+    id
+
+parseAmount ::
   Stream s Identity Char =>
-  ParsecT s u Identity TransactionAmount
-parseTransactionAmount =
-  TransactionAmount <$>
+  ParsecT s u Identity Amount
+parseAmount =
+  Amount <$>
     try (True <$ char '-' <|> pure False) <*>
     some1 parseDecimal <*
     char '.' <*>
     parseDecimal <*>
     parseDecimal
 
-decodeTransactionAmount ::
-  Decode' ByteString TransactionAmount
-decodeTransactionAmount =
-  D.withParsec parseTransactionAmount
+decodeAmount ::
+  Decode' ByteString Amount
+decodeAmount =
+  D.withParsec parseAmount
 
-encodeTransactionAmount ::
+encodeAmount ::
   String
-  -> NameEncode TransactionAmount
-encodeTransactionAmount label =
-  fromString label =: E.mkEncodeBS (\(TransactionAmount n d c1 c2) ->
+  -> NameEncode Amount
+encodeAmount label =
+  fromString label =: E.mkEncodeBS (\(Amount n d c1 c2) ->
     L.fromString (concat [bool "" "-" n, fmap (charDecimal #) (toList d), ".", [charDecimal # c1], [charDecimal # c2]]))
 
-realTransactionAmount ::
+realAmount ::
   Integral a =>
-  TransactionAmount
+  Amount
   -> Ratio a
-realTransactionAmount (TransactionAmount n ds d1 d2) =
+realAmount (Amount n ds d1 d2) =
   let neg =
         if n then Left else Right
   in  (decDigitsIntegral (neg ds) * 100 + decDigitsIntegral (Right (d1 :| [d2]))) % 100
@@ -240,9 +452,9 @@
 data Transaction =
   Transaction {
     _date ::
-      TransactionDate
+      Date
   , _amount ::
-      TransactionAmount
+      Amount
   , _accountNumber ::
       String
   , _emptyField ::
@@ -252,25 +464,82 @@
   , _details ::
       String
   , _balance ::
-      TransactionAmount
+      Amount
   , _category ::
       String
   , _merchantName ::
       String
   } deriving (Eq, Ord, Show)
 
-makeLenses ''Transaction
+class AsTransaction a where
+  _Transaction ::
+    Prism' a Transaction
 
+instance AsTransaction Transaction where
+  _Transaction =
+    id
+
+class HasTransaction a where
+  transaction ::
+    Lens' a Transaction
+  accountNumber ::
+    Lens' a String
+  accountNumber =
+    transaction .
+    \f (Transaction dt am an ef tt dl bl ct mn) -> fmap (\an' -> Transaction dt am an' ef tt dl bl ct mn) (f an)
+  emptyField ::
+    Lens' a String
+  emptyField =
+    transaction .
+    \f (Transaction dt am an ef tt dl bl ct mn) -> fmap (\ef' -> Transaction dt am an ef' tt dl bl ct mn) (f ef)
+  transactionType ::
+    Lens' a String
+  transactionType =
+    transaction .
+    \f (Transaction dt am an ef tt dl bl ct mn) -> fmap (\tt' -> Transaction dt am an ef tt' dl bl ct mn) (f tt)
+  details ::
+    Lens' a String
+  details =
+    transaction .
+    \f (Transaction dt am an ef tt dl bl ct mn) -> fmap (\dl' -> Transaction dt am an ef tt dl' bl ct mn) (f dl)
+  balance ::
+    Lens' a Amount
+  balance =
+    transaction .
+    \f (Transaction dt am an ef tt dl bl ct mn) -> fmap (\bl' -> Transaction dt am an ef tt dl bl' ct mn) (f bl)
+  category ::
+    Lens' a String
+  category =
+    transaction .
+    \f (Transaction dt am an ef tt dl bl ct mn) -> fmap (\ct' -> Transaction dt am an ef tt dl bl ct' mn) (f ct)
+  merchantName ::
+    Lens' a String
+  merchantName =
+    transaction .
+    \f (Transaction dt am an ef tt dl bl ct mn) -> fmap (\mn' -> Transaction dt am an ef tt dl bl ct mn') (f mn)
+
+instance HasTransaction Transaction where
+  transaction =
+    id
+
+instance HasDate Transaction where
+  date f (Transaction dt am an ef tt dl bl ct mn) =
+    fmap (\dt' -> Transaction dt' am an ef tt dl bl ct mn) (f dt)
+
+instance HasAmount Transaction where
+  amount f (Transaction dt am an ef tt dl bl ct mn) =
+    fmap (\am' -> Transaction dt am' an ef tt dl bl ct mn) (f am)
+
 encodeTransaction ::
   NameEncode Transaction
 encodeTransaction =
-  contramap _date encodeTransactionDate <>
-  contramap _amount (encodeTransactionAmount "Amount") <>
+  contramap _date encodeDate <>
+  contramap _amount (encodeAmount "Amount") <>
   fromString "Account Number" =: contramap _accountNumber E.string <>
   fromString "" =: contramap _emptyField E.string <>
   fromString "Transaction Type" =: contramap _transactionType E.string <>
   fromString "Transaction Details" =: contramap _details E.string <>
-  contramap _balance (encodeTransactionAmount "Balance") <>
+  contramap _balance (encodeAmount "Balance") <>
   fromString "Category" =: contramap _category E.string <>
   fromString "Merchant Name" =: contramap _merchantName E.string
 
@@ -278,19 +547,19 @@
   Decode ByteString ByteString Transaction
 decodeTransaction =
   Transaction <$>
-    decodeTransactionDate <*>
-    decodeTransactionAmount <*>
+    decodeDate <*>
+    decodeAmount <*>
     D.string <*>
     D.string <*>
     D.string <*>
     D.string <*>
-    decodeTransactionAmount <*>
+    decodeAmount <*>
     D.string <*>
     D.string
 
 date' ::
   MonadReader Transaction f =>
-  f TransactionDate
+  f Date
 date' =
   view date
 
@@ -298,11 +567,11 @@
   MonadReader Transaction f =>
   f Day
 dateDay' =
-  fmap transactionDateDay date'
+  fmap dateDay date'
 
 amount' ::
   MonadReader Transaction f =>
-  f TransactionAmount
+  f Amount
 amount' =
   view amount
 
@@ -310,7 +579,7 @@
   (MonadReader Transaction f, Integral b) =>
   f (Ratio b)
 amountRatio' =
-  fmap realTransactionAmount amount'
+  fmap realAmount amount'
 
 accountNumber' ::
   MonadReader Transaction f =>
@@ -338,7 +607,7 @@
 
 balance' ::
   MonadReader Transaction f =>
-  f TransactionAmount
+  f Amount
 balance' =
   view balance
 
@@ -346,7 +615,7 @@
   (MonadReader Transaction f, Integral b) =>
   f (Ratio b)
 balanceRatio' =
-  fmap realTransactionAmount balance'
+  fmap realAmount balance'
 
 category' ::
   MonadReader Transaction f =>