diff --git a/buildtool/task/compile_smali.py b/buildtool/task/compile_smali.py
index b45ec8b..78c3f10 100644
--- a/buildtool/task/compile_smali.py
+++ b/buildtool/task/compile_smali.py
@@ -1,11 +1,8 @@
 import subprocess
 from .util import *
-from . import fileutil
 
 import re
 
-from polly.patcher import process_all_patches
-
 # Task dependencies
 from .patch_smali import patch_smali
 
@@ -32,4 +29,4 @@ def compile_smali():
             continue
         
         print(f"Compiling {smali_dir.name} => {dest_dex.name}...")        
-        _ = subprocess.run(["java", "-jar", "tools/smali-3.0.5.jar", "a", "-a", "26", smali_dir, "-o", dest_dex])
\ No newline at end of file
+        _ = subprocess.run([JAVA_BIN, "-jar", SMALI_COMPILER, "a", "-a", "26", smali_dir, "-o", dest_dex])
\ No newline at end of file
diff --git a/buildtool/task/extract.py b/buildtool/task/extract.py
index 2b6112d..4ec6b68 100644
--- a/buildtool/task/extract.py
+++ b/buildtool/task/extract.py
@@ -22,4 +22,4 @@ def extract():
     
     # Extract the apk
     print("Extracting APK...")
-    _ = subprocess.run(['java', '-jar', './tools/apktool_2.9.3.jar', 'd', str(target_apk.absolute()), '-o', EXTRACTED_DIR])
\ No newline at end of file
+    _ = subprocess.run([JAVA_BIN, '-jar', APKTOOL, 'd', str(target_apk.absolute()), '-o', EXTRACTED_DIR])
\ No newline at end of file
diff --git a/buildtool/task/util.py b/buildtool/task/util.py
index d5e2143..63a466a 100644
--- a/buildtool/task/util.py
+++ b/buildtool/task/util.py
@@ -1,4 +1,14 @@
 from pathlib import Path
+import platform
+
+def determine_system():
+    if platform.system() == 'Windows':
+        return 'windows.exe'
+    elif platform.system() in ['Linux', 'Darwin']:
+        return "linux"
+    else:
+        print(f"Unknown system: {platform.system()}")
+        exit(-1)    
 
 SOURCE_APK_DIR = Path("source-apk")
 
@@ -13,4 +23,12 @@ SRC_DIR = Path("src")
 SRC_RESOURCES_DIR = SRC_DIR / "resources"
 SRC_SMALI_DIR = SRC_DIR / "smali"
 SRC_RESOURCE_PATCHES_DIR = SRC_DIR / "patches" / "resource"
-SRC_SMALI_PATCHES_DIR = SRC_DIR / "patches" / "smali"
\ No newline at end of file
+SRC_SMALI_PATCHES_DIR = SRC_DIR / "patches" / "smali"
+
+# Tools
+
+JAVA_BIN = "java"
+APKTOOL = "tools/apktool_2.9.3.jar"
+SMALI_COMPILER = "tools/smali-3.0.5.jar"
+APKSIGNER = 'tools/apksigner.jar'
+ZIPALIGN = 'tools/zipalign-' + determine_system()
\ No newline at end of file
diff --git a/tools/zipalign-linux b/tools/zipalign-linux
new file mode 100644
index 0000000..54862cb
Binary files /dev/null and b/tools/zipalign-linux differ
diff --git a/tools/zipalign-windows.exe b/tools/zipalign-windows.exe
new file mode 100644
index 0000000..323e95d
Binary files /dev/null and b/tools/zipalign-windows.exe differ