diff --git a/src/main.py b/src/main.py
index 93f3ebd..bd095c5 100644
--- a/src/main.py
+++ b/src/main.py
@@ -6,13 +6,24 @@
 
 from src import port
 from src import log
+from src import tokenize
+from src import parse
 from src import oldparse
 from src import interp
 
 
 def run_file(file, log_level=log.NORMAL):
     log.set_default_log_level(log_level)
-    ast = oldparse.parse_file(file)
+    ast = None
+    if os.getenv("NEWLANG_NEW_PARSE"):
+        try:
+            code = open(file, encoding="utf-8").read()
+            tokens = tokenize.tokenize(code, file)
+            ast = parse.parse(tokens, None)
+        except UnicodeDecodeError:
+            pass
+    else:
+        ast = oldparse.parse_file(file)
     if not ast:
         return 1
     interp.run_ast(ast)