diff --git a/.travis.yml b/.travis.yml
--- a/.travis.yml
+++ b/.travis.yml
@@ -41,9 +41,13 @@
       compiler: ": #GHC 7.10.1"
       addons: {apt: {packages: [cabal-install-1.22,ghc-7.10.1,alex-3.1.4,happy-1.19.5], sources: [hvr-ghc]}}
 
-    - env: CABALVER=1.22 GHCVER=7.10.2 BUILD=cabal
-      compiler: ": #GHC 7.10.2"
-      addons: {apt: {packages: [cabal-install-1.22,ghc-7.10.2,alex-3.1.4,happy-1.19.5], sources: [hvr-ghc]}}
+    - env: CABALVER=1.22 GHCVER=7.10.3 BUILD=cabal
+      compiler: ": #GHC 7.10.3"
+      addons: {apt: {packages: [cabal-install-1.22,ghc-7.10.3,alex-3.1.4,happy-1.19.5], sources: [hvr-ghc]}}
+
+    - env: CABALVER=1.24 GHCVER=8.0.1 BUILD=cabal
+      compiler: ": #GHC 8.0.1"
+      addons: {apt: {packages: [cabal-install-1.24,ghc-8.0.1,alex-3.1.4,happy-1.19.5], sources: [hvr-ghc]}}
 
     - env: BUILD=stack
       os: osx
diff --git a/CHANGELOG.markdown b/CHANGELOG.markdown
--- a/CHANGELOG.markdown
+++ b/CHANGELOG.markdown
@@ -1,3 +1,8 @@
+0.8.3
+-----
+* Manual `Generic1` support to work around a bug in GHC 7.6
+* Invert the dependency to supply the `Semigroup` instance ourselves when building on GHC 8
+
 0.8.2
 -------
 * `deepseq` support.
diff --git a/old/Data/Proxy.hs b/old/Data/Proxy.hs
--- a/old/Data/Proxy.hs
+++ b/old/Data/Proxy.hs
@@ -11,7 +11,9 @@
 #endif
 #if __GLASGOW_HASKELL__ >= 702
 {-# LANGUAGE DeriveGeneric #-}
+{-# LANGUAGE EmptyDataDecls #-}
 {-# LANGUAGE Trustworthy #-}
+{-# LANGUAGE TypeFamilies #-}
 #endif
 {-# OPTIONS_GHC -fno-warn-orphans #-}
 ----------------------------------------------------------------------------
@@ -45,7 +47,7 @@
 import GHC.Arr (unsafeIndex, unsafeRangeSize)
 import Data.Data
 #if __GLASGOW_HASKELL__ >= 702
-import GHC.Generics (Generic)
+import GHC.Generics hiding (Fixity(..))
 #endif
 #endif
 
@@ -55,6 +57,27 @@
 data Proxy s = Proxy
 #if __GLASGOW_HASKELL__ >= 702
   deriving Generic
+
+-- We have to implement the Generic1 instance manually due to an old
+-- bug in GHC 7.6. This is mostly copied from the output of
+--
+-- deriving instance Generic1 Proxy
+--
+-- Compiled with -ddump-deriv on a more recent GHC.
+instance Generic1 Proxy where
+  type Rep1 Proxy = D1 ProxyMetaData (C1 ProxyMetaCons U1)
+  from1 Proxy = M1 (M1 U1)
+  to1 (M1 (M1 U1)) = Proxy
+
+data ProxyMetaData
+data ProxyMetaCons
+
+instance Datatype ProxyMetaData where
+  datatypeName _ = "Proxy"
+  moduleName   _ = "Data.Proxy"
+
+instance Constructor ProxyMetaCons where
+  conName _ = "Proxy"
 #endif
 #endif
 
diff --git a/src/Data/Tagged.hs b/src/Data/Tagged.hs
--- a/src/Data/Tagged.hs
+++ b/src/Data/Tagged.hs
@@ -60,9 +60,12 @@
 import Data.Data
 #endif
 import Data.Ix (Ix(..))
-#if defined(__GLASGOW_HASKELL__) && __GLASGOW_HASKELL__ < 707
+#if __GLASGOW_HASKELL__ < 707
 import Data.Proxy
 #endif
+#if __GLASGOW_HASKELL__ >= 800
+import Data.Semigroup (Semigroup(..))
+#endif
 #if __GLASGOW_HASKELL__ >= 702
 import GHC.Generics (Generic)
 #if __GLASGOW_HASKELL__ >= 706
@@ -137,9 +140,19 @@
     readsPrec d = readParen (d > 10) $ \r ->
         [(Tagged a, t) | ("Tagged", s) <- lex r, (a, t) <- readsPrec 11 s]
 
+#if __GLASGOW_HASKELL__ >= 800
+instance Semigroup a => Semigroup (Tagged s a) where
+    Tagged a <> Tagged b = Tagged (a <> b)
+    stimes n (Tagged a)  = Tagged (stimes n a)
+
+instance (Semigroup a, Monoid a) => Monoid (Tagged s a) where
+    mempty = Tagged mempty
+    mappend = (<>)
+#else
 instance Monoid a => Monoid (Tagged s a) where
     mempty = Tagged mempty
     mappend (Tagged a) (Tagged b) = Tagged (mappend a b)
+#endif
 
 instance Functor (Tagged s) where
     fmap f (Tagged x) = Tagged (f x)
@@ -162,13 +175,15 @@
     {-# INLINE pure #-}
     Tagged f <*> Tagged x = Tagged (f x)
     {-# INLINE (<*>) #-}
+    _ *> n = n
+    {-# INLINE (*>) #-}
 
 instance Monad (Tagged s) where
-    return = Tagged
+    return = pure
     {-# INLINE return #-}
     Tagged m >>= k = k m
     {-# INLINE (>>=) #-}
-    _ >> n = n
+    (>>) = (*>)
     {-# INLINE (>>) #-}
 
 instance Foldable (Tagged s) where
diff --git a/tagged.cabal b/tagged.cabal
--- a/tagged.cabal
+++ b/tagged.cabal
@@ -1,5 +1,5 @@
 name:           tagged
-version:        0.8.2
+version:        0.8.3
 license:        BSD3
 license-file:   LICENSE
 author:         Edward A. Kmett