diff --git a/essence-of-live-coding-pulse.cabal b/essence-of-live-coding-pulse.cabal
--- a/essence-of-live-coding-pulse.cabal
+++ b/essence-of-live-coding-pulse.cabal
@@ -1,5 +1,5 @@
 name:                essence-of-live-coding-pulse
-version:             0.2.7
+version:             0.2.8
 synopsis: General purpose live coding framework - pulse backend
 description:
   essence-of-live-coding is a general purpose and type safe live coding framework.
@@ -29,8 +29,8 @@
   exposed-modules:
     LiveCoding.Pulse
   build-depends:
-      base >= 4.11 && < 5
-    , essence-of-live-coding >= 0.2.7
+      base >= 4.13 && < 4.21
+    , essence-of-live-coding >= 0.2.8
     , transformers >= 0.5
     , pulse-simple >= 0.1
     , foreign-store >= 0.2
diff --git a/src/LiveCoding/Pulse.hs b/src/LiveCoding/Pulse.hs
--- a/src/LiveCoding/Pulse.hs
+++ b/src/LiveCoding/Pulse.hs
@@ -25,11 +25,11 @@
 type PulseCell m a b = Cell (PulseT m) a b
 
 -- | Compose with this cell to play a sound sample.
-addSample :: Monad m => PulseCell m Float ()
+addSample :: (Monad m) => PulseCell m Float ()
 addSample = arr Sum >>> arrM tell
 
 -- | Globally fix the sample rate to 48000 samples per second.
-sampleRate :: Num a => a
+sampleRate :: (Num a) => a
 sampleRate = 48000
 
 {- | Create a pulse server backend handle.