diff --git a/code.txt b/code.txt
old mode 100644
new mode 100755
index a7c109e..07d050c
--- a/code.txt
+++ b/code.txt
@@ -1,3 +1,4 @@
+#!./main.py
 BeginNote
 This is a comment and should be ignored by the parser
 EndNote
diff --git a/main.py b/main.py
old mode 100644
new mode 100755
index a610798..000f6b6
--- a/main.py
+++ b/main.py
@@ -1,3 +1,4 @@
+#!/usr/bin/env python3
 # SPDX-License-Identifier: MIT
 # Copyright 2021 Jookia <contact@jookia.org>
 
@@ -30,8 +31,17 @@
             text += symbol
     return tokens
 
-testcode = open("code.txt").read()
-tokens = tokenizer(testcode)
+def main(args):
+    if len(args) != 2:
+        print("Usage: main.py FILENAME")
+        return 1
+    filename = args[1]
+    testcode = open(filename).read()
+    tokens = tokenizer(testcode)
+    for t in tokens:
+        print("TOKEN {0}: {1}".format(t[0], t[1]))
+    return 0
 
-for t in tokens:
-    print("TOKEN {0}: {1}".format(t[0], t[1]))
+if __name__ == "__main__":
+    import sys
+    sys.exit(main(sys.argv))