diff --git a/LICENSE b/LICENSE
--- a/LICENSE
+++ b/LICENSE
@@ -2,27 +2,30 @@
 Copyright © 2011–2014 Wolfgang Jeltsch
 All rights reserved.
 
-Redistribution and use in source and binary forms, with or without modification,
-are permitted provided that the following conditions are met:
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
 
-    • Redistributions of source code must retain the above copyright notice,
-      this list of conditions and the following disclaimer.
+    • Redistributions of source code must retain the above copyright
+      notice, this list of conditions and the following disclaimer.
 
-    • Redistributions in binary form must reproduce the above copyright notice,
-      this list of conditions and the following disclaimer in the documentation
-      and/or other materials provided with the distribution.
+    • Redistributions in binary form must reproduce the above copyright
+      notice, this list of conditions and the following disclaimer in
+      the documentation and/or other materials provided with the
+      distribution.
 
     • Neither the name of the copyright holders nor the names of the
-      contributors may be used to endorse or promote products derived from this
-      software without specific prior written permission.
+      contributors may be used to endorse or promote products derived
+      from this software without specific prior written permission.
 
-THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS “AS IS” AND
-ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
-WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
-DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE
-FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
-DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
-SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
-CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
-TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
-THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS “AS
+IS” AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
+TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
diff --git a/grapefruit-frp.cabal b/grapefruit-frp.cabal
--- a/grapefruit-frp.cabal
+++ b/grapefruit-frp.cabal
@@ -1,5 +1,5 @@
 Name:          grapefruit-frp
-Version:       0.1.0.5
+Version:       0.1.0.6
 Cabal-Version: >= 1.8
 Build-Type:    Simple
 License:       BSD3
@@ -7,10 +7,10 @@
 Copyright:     © 2007–2009 Brandenburgische Technische Universität Cottbus
                © 2011–2014 Wolfgang Jeltsch
 Author:        Wolfgang Jeltsch
-Maintainer:    wolfgang@cs.ioc.ee
+Maintainer:    wolfgang-it@jeltsch.info
 Stability:     provisional
-Homepage:      http://grapefruit-project.org/
-Package-URL:   http://hackage.haskell.org/packages/archive/grapefruit-frp/0.1.0.5/grapefruit-frp-0.1.0.5.tar.gz
+Homepage:      https://grapefruit-project.org/
+Package-URL:   https://hackage.haskell.org/package/grapefruit-frp-0.1.0.6/grapefruit-frp-0.1.0.6.tar.gz
 Synopsis:      Functional Reactive Programming core
 Description:   Grapefruit is a library for Functional Reactive Programming (FRP)
                with a focus on user interfaces. FRP makes it possible to
@@ -21,19 +21,23 @@
                This package contains general support for Functional Reactive
                Programming.
 Category:      FRP, Reactivity
-Tested-With:   GHC == 7.6.3
+Tested-With:   GHC == 8.0.1
 
+Source-Repository head
+    Type:     darcs
+    Location: http://hub.darcs.net/jeltsch/grapefruit
+
 Source-Repository this
     Type:     darcs
-    Location: http://darcs.grapefruit-project.org/monolithic/0.1
-    Tag:      grapefruit-0.1.0.5
+    Location: http://hub.darcs.net/jeltsch/grapefruit
+    Tag:      grapefruit-0.1.0.6
 
 Library
     Build-Depends:   arrows      >= 0.2 && < 0.5,
                      base        >= 3.0 && < 5,
                      containers  >= 0.1 && < 0.6,
                      fingertree  >= 0.0 && < 0.2,
-                     semigroups  >= 0.8 && < 0.16,
+                     semigroups  >= 0.8 && < 0.19,
                      TypeCompose >= 0.3 && < 0.10
     if impl(ghc >= 7.8) {
         -- Role annotations are only supported (and needed) from 7.8 onwards.
diff --git a/src/FRP/Grapefruit/Circuit.hs b/src/FRP/Grapefruit/Circuit.hs
--- a/src/FRP/Grapefruit/Circuit.hs
+++ b/src/FRP/Grapefruit/Circuit.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE NoImpredicativeTypes #-}
 -- |This module provides circuits which are descriptions of reactive systems.
 module FRP.Grapefruit.Circuit (
 
diff --git a/src/FRP/Grapefruit/Signal/Incremental/Sequence.hs b/src/FRP/Grapefruit/Signal/Incremental/Sequence.hs
--- a/src/FRP/Grapefruit/Signal/Incremental/Sequence.hs
+++ b/src/FRP/Grapefruit/Signal/Incremental/Sequence.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE NoImpredicativeTypes #-}
 module FRP.Grapefruit.Signal.Incremental.Sequence (
 
     -- * Diffs
@@ -41,7 +42,7 @@
     -- Data
     import           Data.Semigroup as Semigroup
     import           Data.Monoid    as Monoid
-    import           Data.Foldable  as Foldable
+    import           Data.Foldable  as Foldable  (foldl, toList, sum)
     import           Data.Sequence  as Seq       (Seq)
     import qualified Data.Sequence  as Seq
 
diff --git a/src/FRP/Grapefruit/Signal/Incremental/Set.hs b/src/FRP/Grapefruit/Signal/Incremental/Set.hs
--- a/src/FRP/Grapefruit/Signal/Incremental/Set.hs
+++ b/src/FRP/Grapefruit/Signal/Incremental/Set.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE NoImpredicativeTypes #-}
 module FRP.Grapefruit.Signal.Incremental.Set (
 
     -- * Diffs
@@ -74,7 +75,7 @@
     import           FRP.Grapefruit.Signal.Segmented            as SSignal
     import           FRP.Grapefruit.Signal.Incremental          as ISignal    hiding (combine, map)
     import qualified FRP.Grapefruit.Signal.Incremental          as ISignal
-    import qualified FRP.Grapefruit.Signal.Incremental.Sequence as SeqISignal
+    import qualified FRP.Grapefruit.Signal.Incremental.Sequence as SeqISignal hiding (Diff)
 
     {-FIXME:
         There are several occurences of set union, difference and intersection which involve a set
diff --git a/src/Internal/Signal.hs b/src/Internal/Signal.hs
--- a/src/Internal/Signal.hs
+++ b/src/Internal/Signal.hs
@@ -249,7 +249,7 @@
     -}
     (#>) :: (Sampler sampler, Samplee samplee) =>
             sampler era dummy -> samplee era val -> sampler era val
-    (#>) = (<#>) . samplerMap (const id)
+    (#>) = (<#>) . samplerMap (const (\ val -> val))
 
     {-|
         Sampling of signals where the values of the samplee are ignored.
diff --git a/src/Internal/Signal/Continuous/Segment.hs b/src/Internal/Signal/Continuous/Segment.hs
--- a/src/Internal/Signal/Continuous/Segment.hs
+++ b/src/Internal/Signal/Continuous/Segment.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE NoImpredicativeTypes #-}
 {-# OPTIONS_GHC -fno-cse #-}
 module Internal.Signal.Continuous.Segment (
 
diff --git a/src/Internal/Signal/Discrete.hs b/src/Internal/Signal/Discrete.hs
--- a/src/Internal/Signal/Discrete.hs
+++ b/src/Internal/Signal/Discrete.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE NoImpredicativeTypes #-}
 module Internal.Signal.Discrete (
 
     -- * Discrete signal type
diff --git a/src/Internal/Signal/Discrete/ListenerSet.hs b/src/Internal/Signal/Discrete/ListenerSet.hs
--- a/src/Internal/Signal/Discrete/ListenerSet.hs
+++ b/src/Internal/Signal/Discrete/ListenerSet.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE NoImpredicativeTypes #-}
 module Internal.Signal.Discrete.ListenerSet (
 
     ListenerSet,
diff --git a/src/Internal/Signal/Discrete/Vista.hs b/src/Internal/Signal/Discrete/Vista.hs
--- a/src/Internal/Signal/Discrete/Vista.hs
+++ b/src/Internal/Signal/Discrete/Vista.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE NoImpredicativeTypes #-}
 module Internal.Signal.Discrete.Vista (
 
     Vista,
