diff --git a/exec/Main.hs b/exec/Main.hs
index 98bbd54..36a3699 100644
--- a/exec/Main.hs
+++ b/exec/Main.hs
@@ -1,8 +1,11 @@
 module Main where
 
+data OutputMode = WasmBinary | JSWrapper deriving (Show, Eq)
+
 data WasmConfig = WasmConfig {
     inputFile :: String,
-    outputFile :: String
+    outputFile :: String,
+    outputMode :: OutputMode
 } deriving (Show, Eq)
 
 main :: IO ()