diff --git a/src/pebble.py b/src/pebble.py
index d35bb54..b56d3cc 100644
--- a/src/pebble.py
+++ b/src/pebble.py
@@ -1,3 +1,4 @@
+import sys
 from pathlib import Path
 from typing import Optional
 
@@ -7,6 +8,9 @@ from src.token import Token, TokenType
 
 
 class Pebble:
+    had_error: bool = False
+    had_runtime_error: bool = False
+
     @staticmethod
     def run_file(path: str | Path):
         source: str = ""
@@ -19,10 +23,15 @@ class Pebble:
         from src.runner import Runner
         runner: Runner = Runner(source, path)
         runner.run()
+        if Pebble.had_error:
+            exit(65)
+        if Pebble.had_runtime_error:
+            exit(70)
 
     @staticmethod
     def report(position: Position, where: str, msg: str):
-        print(f"({position}) Error{where}: {msg}")
+        print(f"({position}) Error{where}: {msg}", file=sys.stderr)
+        Pebble.had_error = True
 
     @classmethod
     def error(cls, position: Position, msg: str):
@@ -37,4 +46,5 @@ class Pebble:
 
     @classmethod
     def runtime_error(cls, error: PebbleRuntimeError):
-        print(f"{error}\n({error.token.position})")
+        print(f"{error}\n({error.token.position})", file=sys.stderr)
+        Pebble.had_runtime_error = True
diff --git a/src/runner.py b/src/runner.py
index 0948d94..82dffe1 100644
--- a/src/runner.py
+++ b/src/runner.py
@@ -6,6 +6,7 @@ from src.interpreter.interpreter import Interpreter
 from src.interpreter.resolver import Resolver
 from src.lexer import Lexer
 from src.parser.parser import Parser
+from src.pebble import Pebble
 from src.token import Token
 
 
@@ -19,15 +20,26 @@ class Runner:
         tokens: list[Token] = lexer.process()
         print(list(filter(lambda t: t.type not in Parser.IGNORE, tokens)))
 
+        if Pebble.had_error:
+            return
+
         parser: Parser = Parser(tokens)
         program: list[Stmt] = parser.parse()
 
+        if Pebble.had_error:
+            return
+
         interpreter: Interpreter = Interpreter()
         resolver: Resolver = Resolver(interpreter)
 
         resolver.resolve(*program)
+        if Pebble.had_error:
+            return
         interpreter.interpret(program)
 
+        if Pebble.had_runtime_error:
+            return
+
         formatter: Formatter = Formatter()
         with open("formatted.peb", "w") as f:
             f.write(formatter.print(program))