diff --git a/tidal.cabal b/tidal.cabal
--- a/tidal.cabal
+++ b/tidal.cabal
@@ -1,5 +1,5 @@
 name:                tidal
-version:             0.8
+version:             0.8.1
 synopsis:            Pattern language for improvised music
 -- description:
 homepage:            http://tidal.lurk.org/
@@ -32,4 +32,4 @@
                        Sound.Tidal.Params
                        Sound.Tidal.Transition
 
-  Build-depends: base < 5, process, parsec, hosc > 0.13, hashable, colour, containers, time, websockets > 0.8, text, mtl >=2.1, transformers, mersenne-random-pure64,binary, bytestring, hmt
+  Build-depends: base < 5, process, parsec, hosc > 0.13, hashable, colour, containers, time, websockets > 0.8, text, mtl >=2.1, transformers, mersenne-random-pure64 < 0.2.1.0, binary, bytestring, hmt