diff --git a/image.py b/image.py
index e365cca..c90f48e 100644
--- a/image.py
+++ b/image.py
@@ -142,18 +142,30 @@ def cmd_build(verbose):
 
     rootfs_mount = mount_rootfs_image(image_name)
 
+    extra_repos = {
+        'main': {
+            'Server': 'https://gitlab.com/kupfer/packages/prebuilts/-/raw/main/$repo',
+        },
+        'device': {
+            'Server': 'https://gitlab.com/kupfer/packages/prebuilts/-/raw/main/$repo',
+        },
+    }
+
+    if os.path.exists('/prebuilts'):
+        extra_repos = {
+            'main': {
+                'Server': 'file:///prebuilts/$repo',
+            },
+            'device': {
+                'Server': 'file:///prebuilts/$repo',
+            },
+        }
+
     create_chroot(
         rootfs_mount,
         packages=(['base', 'base-kupfer'] + devices[device] + flavours[flavour]),
         pacman_conf='/app/local/etc/pacman.conf',
-        extra_repos={
-            'main': {
-                'Server': 'https://gitlab.com/kupfer/packages/prebuilts/-/raw/main/$repo',
-            },
-            'device': {
-                'Server': 'https://gitlab.com/kupfer/packages/prebuilts/-/raw/main/$repo',
-            },
-        },
+        extra_repos=extra_repos,
     )
     create_chroot_user(rootfs_mount)
 
diff --git a/wrapper.py b/wrapper.py
index bc57485..44d27cf 100644
--- a/wrapper.py
+++ b/wrapper.py
@@ -58,6 +58,13 @@ else:
 
         atexit.register(at_exit)
 
+        prebuilts_mount = []
+        if os.getenv('KUPFERBOOTSTRAP_PREBUILTS') != '':
+            prebuilts_mount = [
+                '-v',
+                f'{os.getenv("KUPFERBOOTSTRAP_PREBUILTS")}:/prebuilts:z',
+            ]
+
         subprocess.run([
             'docker',
             'run',
@@ -69,6 +76,7 @@ else:
             '--privileged',
             '-v',
             f'{os.getcwd()}:/src:z',
+        ] + prebuilts_mount + [
             '-v',
             f'{os.path.join(appdirs.user_cache_dir("kupfer"),"chroot")}:/chroot:z',
             '-v',