diff --git a/reactive.cabal b/reactive.cabal
--- a/reactive.cabal
+++ b/reactive.cabal
@@ -1,5 +1,5 @@
 Name:                reactive
-Version:             0.11.4
+Version:             0.11.5
 Synopsis:            Push-pull functional reactive programming
 Category:            reactivity, FRP
 Description:
@@ -44,7 +44,7 @@
 Extra-Source-Files:
 Library
     Build-Depends:       base >=4 && <5, old-time, random, QuickCheck >= 2.1.0.2,
-                         TypeCompose>=0.6.3, vector-space>=0.5,
+                         TypeCompose>=0.8.0, vector-space>=0.5,
                          unamb>=0.1.5, checkers >= 0.2.3,
                          category-extras >= 0.53.5, Stream >= 0.3.1
     -- This library uses the ImpredicativeTypes flag, and it depends
diff --git a/src/FRP/Reactive/Behavior.hs b/src/FRP/Reactive/Behavior.hs
--- a/src/FRP/Reactive/Behavior.hs
+++ b/src/FRP/Reactive/Behavior.hs
@@ -31,7 +31,7 @@
 
 import Control.Comonad
 
-import Control.Compose ((:.)(..))
+import Control.Compose ((:.)(..),unO)
 
 import Data.VectorSpace
 import Data.AffineSpace
diff --git a/src/FRP/Reactive/Internal/Behavior.hs b/src/FRP/Reactive/Internal/Behavior.hs
--- a/src/FRP/Reactive/Internal/Behavior.hs
+++ b/src/FRP/Reactive/Internal/Behavior.hs
@@ -21,7 +21,7 @@
 import Control.Applicative (Applicative(pure),liftA2)
 
 -- TypeCompose
-import Control.Compose ((:.)(..))
+import Control.Compose ((:.)(..),unO)
 import Data.Zip (Zip(..),Unzip(..))
 
 import qualified FRP.Reactive.Reactive as R
diff --git a/src/FRP/Reactive/Internal/TVal.hs b/src/FRP/Reactive/Internal/TVal.hs
--- a/src/FRP/Reactive/Internal/TVal.hs
+++ b/src/FRP/Reactive/Internal/TVal.hs
@@ -243,7 +243,7 @@
                                       readChan chanB >>= snk
                                       loop
 
-                 forkIO loop
+                 _ <- forkIO loop
                  as  <- getChanStream chanA
 
                  -- debugging.  defeats freeing.
diff --git a/src/FRP/Reactive/VectorSpace.hs b/src/FRP/Reactive/VectorSpace.hs
--- a/src/FRP/Reactive/VectorSpace.hs
+++ b/src/FRP/Reactive/VectorSpace.hs
@@ -10,7 +10,6 @@
 import Control.Applicative
 
 import Data.VectorSpace
-import Data.AdditiveGroup
 
 instance AdditiveGroup v => AdditiveGroup (Behavior v) where
   zeroV   = pure   zeroV