diff --git a/ChangeLog b/ChangeLog
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,12 @@
+Version 0.4.0.0
+
+* Added Exception instances (requires major version bump)
+
+* Added S0
+
+* Removed Generics instances; including them makes compatibility
+  with GHC 7.4 more difficult.  (requires major version bump)
+
 Version 0.2.2.0
 
-* added S1
+* added S1.  Still debating whether and how to add S0.
diff --git a/Data/Sums.hs b/Data/Sums.hs
--- a/Data/Sums.hs
+++ b/Data/Sums.hs
@@ -1,4 +1,5 @@
-{-# LANGUAGE DeriveDataTypeable, DeriveGeneric #-}
+{-# LANGUAGE DeriveDataTypeable #-}
+{-# LANGUAGE EmptyDataDecls #-}
 
 -- Text of this module generated by the generate-sums.hs
 -- script, included with the source of the anonymous-sums
@@ -13,42 +14,60 @@
 module Data.Sums where
 
 import Data.Typeable
-import GHC.Generics hiding (S1)
+import Control.Exception
 
 -- * Anonymous sum types
 
-data S1 a = S1a a deriving (Eq, Ord, Read, Show, Generic, Typeable)
+data S0 deriving Typeable
 
-data S2 a b = S2a a | S2b b deriving (Eq, Ord, Read, Show, Generic, Typeable)
+instance Eq S0 where _ == _ = undefined
+instance Ord S0 where compare _ _ = undefined
+instance Read S0 where readsPrec _ = undefined
+instance Show S0 where show _ = undefined
+instance Exception S0
 
-data S3 a b c = S3a a | S3b b | S3c c deriving (Eq, Ord, Read, Show, Generic, Typeable)
+data S1 a = S1a a deriving (Eq, Ord, Read, Show, Typeable)
+instance (Typeable a, Show a) => Exception (S1 a)
 
-data S4 a b c d = S4a a | S4b b | S4c c | S4d d deriving (Eq, Ord, Read, Show, Generic, Typeable)
+data S2 a b = S2a a | S2b b deriving (Eq, Ord, Read, Show, Typeable)
+instance (Typeable a, Show a, Typeable b, Show b) => Exception (S2 a b)
 
-data S5 a b c d e = S5a a | S5b b | S5c c | S5d d | S5e e deriving (Eq, Ord, Read, Show, Generic, Typeable)
+data S3 a b c = S3a a | S3b b | S3c c deriving (Eq, Ord, Read, Show, Typeable)
+instance (Typeable a, Show a, Typeable b, Show b, Typeable c, Show c) => Exception (S3 a b c)
 
-data S6 a b c d e f = S6a a | S6b b | S6c c | S6d d | S6e e | S6f f deriving (Eq, Ord, Read, Show, Generic, Typeable)
+data S4 a b c d = S4a a | S4b b | S4c c | S4d d deriving (Eq, Ord, Read, Show, Typeable)
+instance (Typeable a, Show a, Typeable b, Show b, Typeable c, Show c, Typeable d, Show d) => Exception (S4 a b c d)
 
-data S7 a b c d e f g = S7a a | S7b b | S7c c | S7d d | S7e e | S7f f | S7g g deriving (Eq, Ord, Read, Show, Generic, Typeable)
+data S5 a b c d e = S5a a | S5b b | S5c c | S5d d | S5e e deriving (Eq, Ord, Read, Show, Typeable)
+instance (Typeable a, Show a, Typeable b, Show b, Typeable c, Show c, Typeable d, Show d, Typeable e, Show e) => Exception (S5 a b c d e)
 
-data S8 a b c d e f g h = S8a a | S8b b | S8c c | S8d d | S8e e | S8f f | S8g g | S8h h deriving (Eq, Ord, Read, Show, Generic)
+data S6 a b c d e f = S6a a | S6b b | S6c c | S6d d | S6e e | S6f f deriving (Eq, Ord, Read, Show, Typeable)
+instance (Typeable a, Show a, Typeable b, Show b, Typeable c, Show c, Typeable d, Show d, Typeable e, Show e, Typeable f, Show f) => Exception (S6 a b c d e f)
 
-data S9 a b c d e f g h i = S9a a | S9b b | S9c c | S9d d | S9e e | S9f f | S9g g | S9h h | S9i i deriving (Eq, Ord, Read, Show, Generic)
+data S7 a b c d e f g = S7a a | S7b b | S7c c | S7d d | S7e e | S7f f | S7g g deriving (Eq, Ord, Read, Show, Typeable)
+instance (Typeable a, Show a, Typeable b, Show b, Typeable c, Show c, Typeable d, Show d, Typeable e, Show e, Typeable f, Show f, Typeable g, Show g) => Exception (S7 a b c d e f g)
 
-data S10 a b c d e f g h i j = S10a a | S10b b | S10c c | S10d d | S10e e | S10f f | S10g g | S10h h | S10i i | S10j j deriving (Eq, Ord, Read, Show, Generic)
+data S8 a b c d e f g h = S8a a | S8b b | S8c c | S8d d | S8e e | S8f f | S8g g | S8h h deriving (Eq, Ord, Read, Show)
 
-data S11 a b c d e f g h i j k = S11a a | S11b b | S11c c | S11d d | S11e e | S11f f | S11g g | S11h h | S11i i | S11j j | S11k k deriving (Eq, Ord, Read, Show, Generic)
+data S9 a b c d e f g h i = S9a a | S9b b | S9c c | S9d d | S9e e | S9f f | S9g g | S9h h | S9i i deriving (Eq, Ord, Read, Show)
 
-data S12 a b c d e f g h i j k l = S12a a | S12b b | S12c c | S12d d | S12e e | S12f f | S12g g | S12h h | S12i i | S12j j | S12k k | S12l l deriving (Eq, Ord, Read, Show, Generic)
+data S10 a b c d e f g h i j = S10a a | S10b b | S10c c | S10d d | S10e e | S10f f | S10g g | S10h h | S10i i | S10j j deriving (Eq, Ord, Read, Show)
 
-data S13 a b c d e f g h i j k l m = S13a a | S13b b | S13c c | S13d d | S13e e | S13f f | S13g g | S13h h | S13i i | S13j j | S13k k | S13l l | S13m m deriving (Eq, Ord, Read, Show, Generic)
+data S11 a b c d e f g h i j k = S11a a | S11b b | S11c c | S11d d | S11e e | S11f f | S11g g | S11h h | S11i i | S11j j | S11k k deriving (Eq, Ord, Read, Show)
 
-data S14 a b c d e f g h i j k l m n = S14a a | S14b b | S14c c | S14d d | S14e e | S14f f | S14g g | S14h h | S14i i | S14j j | S14k k | S14l l | S14m m | S14n n deriving (Eq, Ord, Read, Show, Generic)
+data S12 a b c d e f g h i j k l = S12a a | S12b b | S12c c | S12d d | S12e e | S12f f | S12g g | S12h h | S12i i | S12j j | S12k k | S12l l deriving (Eq, Ord, Read, Show)
 
-data S15 a b c d e f g h i j k l m n o = S15a a | S15b b | S15c c | S15d d | S15e e | S15f f | S15g g | S15h h | S15i i | S15j j | S15k k | S15l l | S15m m | S15n n | S15o o deriving (Eq, Ord, Read, Show, Generic)
+data S13 a b c d e f g h i j k l m = S13a a | S13b b | S13c c | S13d d | S13e e | S13f f | S13g g | S13h h | S13i i | S13j j | S13k k | S13l l | S13m m deriving (Eq, Ord, Read, Show)
 
+data S14 a b c d e f g h i j k l m n = S14a a | S14b b | S14c c | S14d d | S14e e | S14f f | S14g g | S14h h | S14i i | S14j j | S14k k | S14l l | S14m m | S14n n deriving (Eq, Ord, Read, Show)
+
+data S15 a b c d e f g h i j k l m n o = S15a a | S15b b | S15c c | S15d d | S15e e | S15f f | S15g g | S15h h | S15i i | S15j j | S15k k | S15l l | S15m m | S15n n | S15o o deriving (Eq, Ord, Read, Show)
+
 -- * Partitioning
 
+partitionS0 :: [S0] -> ()
+partitionS0 _ = ()
+
 partitionS1 :: [S1 a] -> ([a])
 partitionS1 = foldr fn ([])
   where
@@ -246,6 +265,9 @@
 
 -- * Case analysis
 
+caseS0 :: S0 -> z
+caseS0 = undefined
+
 caseS1 :: (a -> z) -> S1 a -> z
 caseS1 fa s1 = case s1 of
   S1a a -> fa a
@@ -413,6 +435,9 @@
 
 -- * Mapping
 
+mapS0 :: S0 -> S0
+mapS0 = id
+
 mapS1 :: (a -> a1) -> S1 a -> S1 a1
 mapS1 a = caseS1 (S1a . a)
 
@@ -459,6 +484,9 @@
 mapS15 a b c d e f g h i j k l m n o = caseS15 (S15a . a) (S15b . b) (S15c . c) (S15d . d) (S15e . e) (S15f . f) (S15g . g) (S15h . h) (S15i . i) (S15j . j) (S15k . k) (S15l . l) (S15m . m) (S15n . n) (S15o . o)
 
 -- * Mapping in a Functor
+
+mapS0f :: Functor ftr => S0 -> ftr S0
+mapS0f = undefined
 
 mapS1f :: Functor ftr =>
   (a -> ftr a1) -> S1 a -> ftr (S1 a1)
diff --git a/Makefile b/Makefile
new file mode 100644
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,15 @@
+Data/Sums.hs : generate-sums.hs
+	runghc generate-sums.hs Data.Sums 15 > Data/Sums.hs
+
+clean :
+	rm Data/Sums.hs
+	runhaskell Setup clean
+
+dist : Data/Sums.hs
+	runhaskell Setup configure 
+	runhaskell Setup sdist
+
+test : Data/Sums.hs sunlight-test.hs
+	runghc sunlight-test.hs
+
+.PHONY: clean
diff --git a/anonymous-sums.cabal b/anonymous-sums.cabal
--- a/anonymous-sums.cabal
+++ b/anonymous-sums.cabal
@@ -2,7 +2,7 @@
 -- documentation, see http://haskell.org/cabal/users-guide/
 
 name:                anonymous-sums
-version:             0.2.2.0
+version:             0.4.0.0
 synopsis:            Anonymous sum types
 description:
   Anonymous sum types.  Like tuples, but for sum types rather than
@@ -16,18 +16,25 @@
 category:            Data
 build-type:          Simple
 cabal-version:       >=1.10
-extra-source-files: README.md, ChangeLog
+extra-source-files: README.md, ChangeLog, Makefile
+tested-with: GHC==7.4.1, GHC==7.6.3
+source-repository head
+  type: git
+  location: https://github.com/massysett/anonymous-sums.git
 
+
+-- Dependencies reflect ghc 7.6.  ghc 7.4 had a different
+-- Generics interface.
 library
   exposed-modules: Data.Sums
-  build-depends:       base >=4.6 && <5
+  build-depends:       base >=4.5.0.0 && <5
   default-language:    Haskell2010
   ghc-options: -Wall
 
 Executable generate-sums
   main-is: generate-sums.hs
   ghc-options: -Wall
-  build-depends: base >=4.6 && <5
+  build-depends: base >=4.5.0.0 && <5
   default-language: Haskell2010
   if ! flag (build-generator)
     buildable: False
@@ -35,3 +42,4 @@
 Flag build-generator
   Description: Build binary to generate program source
   Default: False
+
diff --git a/generate-sums.hs b/generate-sums.hs
--- a/generate-sums.hs
+++ b/generate-sums.hs
@@ -7,27 +7,64 @@
 
 dataDeclaration
   :: Int
-  -- ^ Number of type variables
+  -- ^ Number of type variables. Must be at least 0.
   -> String
-dataDeclaration i =
+dataDeclaration i
+  | i == 0 = dataDeclaration0
+  | otherwise = dataDeclarationN i
+
+dataDeclaration0 :: String
+dataDeclaration0 = unlines
+  [ "data S0 deriving Typeable"
+  , ""
+  , "instance Eq S0 where _ == _ = undefined"
+  , "instance Ord S0 where compare _ _ = undefined"
+  , "instance Read S0 where readsPrec _ = undefined"
+  , "instance Show S0 where show _ = undefined"
+  , "instance Exception S0"
+  , ""
+  ]
+
+
+dataDeclarationN
+  :: Int
+  -- ^ Number of type variables.  Must be at least 1.
+  -> String
+dataDeclarationN i =
   "data " ++ sType i ++ " = "
   ++ constructors
-  ++ " deriving (Eq, Ord, Read, Show, Generic"
+  ++ " deriving (Eq, Ord, Read, Show"
   ++ (if i <= 7 then ", Typeable)" else ")")
-  ++ "\n\n"
+  ++ "\n"
+  ++ exceptionInstance i
   where
     constructors = list " | " . map mkConst
       $ ls
     mkConst l = 'S' : show i ++ l : ' ' : l : []
     ls = letters i
 
+exceptionInstance :: Int -> String
+exceptionInstance i
+  | i > 7 = "\n"
+  | otherwise = "instance " ++ constraint
+    ++ "Exception (" ++ sType i ++ ")\n\n"
+  where
+    constraint
+      | i == 0 = ""
+      | otherwise = "(" ++ list ", " ls ++ ") => "
+      where
+        ls = map constrain . letters $ i
+        constrain c = "Typeable " ++ s ++ ", Show " ++ s
+          where s = [c]
+
 letter :: Int -> Char
 letter i = toEnum (97 + i)
 
 sType :: Int -> String
 sType i = 'S' : show i ++ types
   where
-    types = " " ++ intersperse ' ' ls
+    types | i == 0 = ""
+          | otherwise = " " ++ intersperse ' ' ls
     ls = letters i
 
 letters :: Int -> [Char]
@@ -37,7 +74,19 @@
 list s = concat . intersperse s
 
 partitionDef :: Int -> String
-partitionDef i = sig ++ decl
+partitionDef i
+  | i == 0 = partitionDef0
+  | otherwise = partitionDefN i
+
+partitionDef0 :: String
+partitionDef0 = unlines
+  [ "partitionS0 :: [S0] -> ()"
+  , "partitionS0 _ = ()"
+  , ""
+  ]
+
+partitionDefN :: Int -> String
+partitionDefN i = sig ++ decl
   where
     sig = fName ++ " :: ["
       ++ sType i ++ "] -> " ++ tuple ++ "\n"
@@ -69,7 +118,19 @@
               | otherwise = ltr : 's' : []
 
 caseDef :: Int -> String
-caseDef i = sig ++ decl
+caseDef i
+  | i == 0 = caseDef0
+  | otherwise = caseDefN i
+
+caseDef0 :: String
+caseDef0 = unlines
+  [ "caseS0 :: S0 -> z"
+  , "caseS0 = undefined"
+  , ""
+  ]
+
+caseDefN :: Int -> String
+caseDefN i = sig ++ decl
   where
     sig = fName ++ " :: " ++ fns
       ++ " -> " ++ sType i ++ " -> z\n"
@@ -87,7 +148,19 @@
       : " -> " ++ ('f' : l : ' ' : l : "\n")
 
 mapDef :: Int -> String
-mapDef i = sig ++ decl
+mapDef i
+  | i == 0 = mapDef0
+  | otherwise = mapDefN i
+
+mapDef0 :: String
+mapDef0 = unlines
+  [ "mapS0 :: S0 -> S0"
+  , "mapS0 = id"
+  , ""
+  ]
+
+mapDefN :: Int -> String
+mapDefN i = sig ++ decl
   where
     fName = "mapS" ++ show i
     sig = fName ++ " :: " ++ list " -> "
@@ -104,7 +177,19 @@
     mkMapper l = "(S" ++ show i ++ l : " . " ++ l : ")"
 
 mapDefA :: Int -> String
-mapDefA i = sig ++ decl
+mapDefA i
+  | i == 0 = mapDefA0
+  | otherwise = mapDefAN i
+
+mapDefA0 :: String
+mapDefA0 = unlines
+  [ "mapS0f :: Functor ftr => S0 -> ftr S0"
+  , "mapS0f = undefined"
+  , ""
+  ]
+
+mapDefAN :: Int -> String
+mapDefAN i = sig ++ decl
   where
     fName = "mapS" ++ show i ++ "f"
     sig = fName ++ " :: "
@@ -136,7 +221,8 @@
   ++ cases ++ maps ++ mapFs
   where
 
-    pragmas = "{-# LANGUAGE DeriveDataTypeable, DeriveGeneric #-}\n\n"
+    pragmas = "{-# LANGUAGE DeriveDataTypeable #-}\n"
+      ++ "{-# LANGUAGE EmptyDataDecls #-}\n\n"
 
     notice = unlines
       [ "-- Text of this module generated by the generate-sums.hs"
@@ -158,7 +244,7 @@
 
     imports = unlines
       [ "import Data.Typeable"
-      , "import GHC.Generics hiding (S1)"
+      , "import Control.Exception"
       , ""
       ]
 
@@ -177,7 +263,7 @@
     mapFs = "-- * Mapping in a Functor\n\n"
       ++ concatMap mapDefA vs
 
-    vs = [1..i]
+    vs = [0..i]
 
 usage
   :: String