diff --git a/CHANGELOG.markdown b/CHANGELOG.markdown
--- a/CHANGELOG.markdown
+++ b/CHANGELOG.markdown
@@ -1,3 +1,10 @@
+0.4.0.1
+-----
+* Bumped the bounds for `mtl` and `transformers`
+
+0.4
+-----
+
 0.2.5
 -----
 * Added `deconstruct`, `tagDone` and `finishWith`
diff --git a/machines.cabal b/machines.cabal
--- a/machines.cabal
+++ b/machines.cabal
@@ -1,6 +1,6 @@
 name:          machines
 category:      Control, Enumerator
-version:       0.4
+version:       0.4.0.1
 license:       BSD3
 cabal-version: >= 1.10
 license-file:  LICENSE
@@ -43,8 +43,8 @@
     pointed      >= 3,
     profunctors  >= 3,
     semigroups   >= 0.8.3,
-    transformers == 0.3.*,
-    mtl          >= 2 && < 2.2,
+    transformers >= 0.3 && < 0.5,
+    mtl          >= 2 && < 2.3,
     void         >= 0.6.1 && < 0.7
 
   exposed-modules: