diff --git a/semantic-ast/src/CLI.hs b/semantic-ast/src/CLI.hs
index 439db3a71..a13ec10be 100644
--- a/semantic-ast/src/CLI.hs
+++ b/semantic-ast/src/CLI.hs
@@ -14,3 +14,4 @@ import System.IO (FilePath)
 main :: IO ()
 main = do
   args <- head <$> getArgs
+  bytestring <- Data.ByteString.readFile args