diff --git a/language-qux.cabal b/language-qux.cabal
--- a/language-qux.cabal
+++ b/language-qux.cabal
@@ -1,5 +1,5 @@
 name:           language-qux
-version:        0.1.0.1
+version:        0.1.1.0
 
 author:         Henry J. Wylde
 maintainer:     public@hjwylde.com
@@ -29,7 +29,8 @@
         Language.Qux.Syntax,
         Language.Qux.Version
     other-modules:
-        Language.Qux.Lexer
+        Language.Qux.Lexer,
+        Paths_language_qux
 
     default-language: Haskell2010
     build-depends:
diff --git a/src/Language/Qux/Annotated/TypeChecker.hs b/src/Language/Qux/Annotated/TypeChecker.hs
--- a/src/Language/Qux/Annotated/TypeChecker.hs
+++ b/src/Language/Qux/Annotated/TypeChecker.hs
@@ -39,7 +39,7 @@
 import Data.List ((\\), nubBy)
 import Data.Map (Map, (!))
 import qualified Data.Map as Map
-import Data.Maybe
+import Data.Maybe (fromJust, isNothing)
 
 import Language.Qux.Annotated.Exception
 import Language.Qux.Annotated.Parser (SourcePos)
diff --git a/src/Language/Qux/Interpreter.hs b/src/Language/Qux/Interpreter.hs
--- a/src/Language/Qux/Interpreter.hs
+++ b/src/Language/Qux/Interpreter.hs
@@ -38,6 +38,7 @@
 import Data.List ((\\))
 import Data.Map (Map, (!))
 import qualified Data.Map as Map
+import Data.Maybe (fromJust, isJust)
 
 import Language.Qux.Syntax
 
@@ -114,9 +115,14 @@
 
 evalApplicationExpr :: Id -> [Value] -> Evaluation Value
 evalApplicationExpr name arguments = do
-    (parameters, stmts) <- asks $ (! name) . functions
+    maybeValue <- gets $ Map.lookup name
 
-    once (Map.union $ Map.fromList (zip parameters arguments)) (runExecution undefined (execBlock stmts))
+    if isJust maybeValue then
+        return $ fromJust maybeValue
+    else do
+        (parameters, stmts) <- asks $ (! name) . functions
+
+        once (Map.union $ Map.fromList (zip parameters arguments)) (runExecution undefined (execBlock stmts))
 
 evalBinaryExpr :: BinaryOp -> Value -> Value -> Evaluation Value
 evalBinaryExpr Acc (ListValue elements) (IntValue rhs)    = return $ elements !! (fromInteger rhs)
diff --git a/src/Language/Qux/Version.hs b/src/Language/Qux/Version.hs
--- a/src/Language/Qux/Version.hs
+++ b/src/Language/Qux/Version.hs
@@ -30,5 +30,5 @@
 minor = 1
 
 -- | The patch component.
-patch = 0
+patch = 1