diff --git a/prelude/prelude.purs b/prelude/prelude.purs
--- a/prelude/prelude.purs
+++ b/prelude/prelude.purs
@@ -313,19 +313,19 @@
 
   instance ordUnit :: Ord Unit where
     compare (Unit {}) (Unit {}) = EQ
-    
+
   instance ordBoolean :: Ord Boolean where
     compare false false = EQ
     compare false true  = LT
     compare true  true  = EQ
     compare true  false = GT
-    
+
   instance ordNumber :: Ord Number where
     compare = unsafeCompare
-    
+
   instance ordString :: Ord String where
     compare = unsafeCompare
-    
+
   instance ordArray :: (Ord a) => Ord [a] where
     compare [] [] = EQ
     compare [] _ = LT
@@ -452,6 +452,115 @@
 
   on :: forall a b c. (b -> b -> c) -> (a -> b) -> a -> a -> c
   on f g x y = g x `f` g y
+
+  foreign import data Fn0 :: * -> *
+  foreign import data Fn1 :: * -> * -> *
+  foreign import data Fn2 :: * -> * -> * -> *
+  foreign import data Fn3 :: * -> * -> * -> * -> *
+  foreign import data Fn4 :: * -> * -> * -> * -> * -> *
+  foreign import data Fn5 :: * -> * -> * -> * -> * -> * -> *
+
+  foreign import mkFn0
+    "function mkFn0(f) {\
+    \  return function() {\
+    \    return f({});\
+    \  };\
+    \}" :: forall a. (Unit -> a) -> Fn0 a
+
+  foreign import mkFn1
+    "function mkFn1(f) {\
+    \  return function(a) {\
+    \    return f(a);\
+    \  };\
+    \}" :: forall a b. (a -> b) -> Fn1 a b
+
+  foreign import mkFn2
+    "function mkFn2(f) {\
+    \  return function(a, b) {\
+    \    return f(a)(b);\
+    \  };\
+    \}" :: forall a b c. (a -> b -> c) -> Fn2 a b c
+
+  foreign import mkFn3
+    "function mkFn3(f) {\
+    \  return function(a, b, c) {\
+    \    return f(a)(b)(c);\
+    \  };\
+    \}" :: forall a b c d. (a -> b -> c -> d) -> Fn3 a b c d
+
+  foreign import mkFn4
+    "function mkFn4(f) {\
+    \  return function(a, b, c, d) {\
+    \    return f(a)(b)(c)(d);\
+    \  };\
+    \}" :: forall a b c d e. (a -> b -> c -> d -> e) -> Fn4 a b c d e
+
+  foreign import mkFn5
+    "function mkFn5(f) {\
+    \  return function(a, b, c, d, e) {\
+    \    return f(a)(b)(c)(d)(e);\
+    \  };\
+    \}" :: forall a b c d e f. (a -> b -> c -> d -> e -> f) -> Fn5 a b c d e f
+
+  foreign import runFn0
+    "function runFn0(f) {\
+    \  return f();\
+    \}" :: forall a. Fn0 a -> a
+
+  foreign import runFn1
+    "function runFn1(f) {\
+    \  return function(a) {\
+    \    return f(a);\
+    \  };\
+    \}" :: forall a b. Fn1 a b -> a -> b
+
+  foreign import runFn2
+    "function runFn2(f) {\
+    \  return function(a) {\
+    \    return function(b) {\
+    \      return f(a, b);\
+    \    };\
+    \  };\
+    \}" :: forall a b c. Fn2 a b c -> a -> b -> c
+
+  foreign import runFn3
+    "function runFn3(f) {\
+    \  return function(a) {\
+    \    return function(b) {\
+    \      return function(c) {\
+    \        return f(a, b, c);\
+    \      };\
+    \    };\
+    \  };\
+    \}" :: forall a b c d. Fn3 a b c d -> a -> b -> c -> d
+
+  foreign import runFn4
+    "function runFn4(f) {\
+    \  return function(a) {\
+    \    return function(b) {\
+    \      return function(c) {\
+    \        return function(d) {\
+    \          return f(a, b, c, d);\
+    \        };\
+    \      };\
+    \    };\
+    \  };\
+    \}" :: forall a b c d e. Fn4 a b c d e -> a -> b -> c -> d -> e
+
+  foreign import runFn5
+    "function runFn5(f) {\
+    \  return function(a) {\
+    \    return function(b) {\
+    \      return function(c) {\
+    \        return function(d) {\
+    \          return function(e) {\
+    \            return f(a, b, c, d, e);\
+    \          };\
+    \        };\
+    \      };\
+    \    };\
+    \  };\
+    \}" :: forall a b c d e f. Fn5 a b c d e f -> a -> b -> c -> d -> e -> f
 
 module Data.Eq where
 
diff --git a/purescript.cabal b/purescript.cabal
--- a/purescript.cabal
+++ b/purescript.cabal
@@ -1,5 +1,5 @@
 name: purescript
-version: 0.5.2.1
+version: 0.5.2.2
 cabal-version: >=1.8
 build-type: Custom
 license: MIT
diff --git a/src/Language/PureScript/Optimizer/TCO.hs b/src/Language/PureScript/Optimizer/TCO.hs
--- a/src/Language/PureScript/Optimizer/TCO.hs
+++ b/src/Language/PureScript/Optimizer/TCO.hs
@@ -95,6 +95,9 @@
     collectSelfCallArgs allArgumentValues (JSApp fn args') = collectSelfCallArgs (args' : allArgumentValues) fn
     collectSelfCallArgs allArgumentValues _ = allArgumentValues
   isSelfCall :: String -> JS -> Bool
-  isSelfCall ident (JSApp (JSVar ident') _) | ident == ident' = True
-  isSelfCall ident (JSApp fn _) = isSelfCall ident fn
+  isSelfCall ident (JSApp (JSVar ident') args) | ident == ident' && not (any isFunction args) = True
+  isSelfCall ident (JSApp fn args) | not (any isFunction args) = isSelfCall ident fn
   isSelfCall _ _ = False
+  isFunction :: JS -> Bool
+  isFunction (JSFunction _ _ _) = True
+  isFunction _ = False