diff --git a/.vscode/launch.json b/.vscode/launch.json
index d6f56e0..85a9464 100644
--- a/.vscode/launch.json
+++ b/.vscode/launch.json
@@ -9,7 +9,7 @@
             "type": "python",
             "request": "launch",
             "program": "dopey.py",
-            "args": ["./test.bf"],
+            "args": ["./helloworld.bf"],
             "console": "integratedTerminal"
         }
     ]
diff --git a/dopey.py b/dopey.py
index 258b5fc..f065adc 100644
--- a/dopey.py
+++ b/dopey.py
@@ -1,4 +1,5 @@
 import sys
+from io import TextIOWrapper
 from blessed import Terminal
 
 # create memory buffer and pointer
@@ -6,6 +7,7 @@ class Memory:
     BUFFER_SIZE = 30_000
     buffer = [0 for _ in range(BUFFER_SIZE)]
     pointer = 0
+    loop_stack = []
 
     @classmethod
     def get_pointer(cls) -> int:
@@ -40,11 +42,11 @@ def main() -> None:
             break
         
         # perform operation
-        perform_operation(operation)
+        perform_operation(operation, file)
 
     file.close()
 
-def perform_operation(operation: str) -> None:
+def perform_operation(operation: str, file: TextIOWrapper) -> None:
     if operation == Operation.SHIFT_LEFT:
         Memory.pointer -= 1
     elif operation == Operation.SHIFT_RIGHT:
@@ -59,6 +61,25 @@ def perform_operation(operation: str) -> None:
         term = Terminal()
         with term.cbreak():
             Memory.buffer[Memory.get_pointer()] = ord(term.inkey())
+    elif operation == Operation.OPEN_LOOP:
+        if Memory.buffer[Memory.get_pointer()] == 0:
+            while True:
+                operation = file.read(1)
+                if operation == Operation.CLOSE_LOOP:
+                    break
+                elif not operation:
+                    print("Mismatched bracket...") # TODO add line number and column on line
+                    sys.exit()
+        else:
+            Memory.loop_stack.append(file.tell()-1)
+    elif operation == Operation.CLOSE_LOOP:
+        if len(Memory.loop_stack) == 0:
+            print("Mismatched bracket...") # TODO add line number and column on line
+            sys.exit()
+            
+        open_loop_position = Memory.loop_stack.pop()
+        if Memory.buffer[Memory.get_pointer()] != 0:
+            file.seek(open_loop_position, 0)
 
 if __name__ == "__main__":
     main()