diff --git a/src/loaih/build.py b/src/loaih/build.py
index 2525f55..07256a0 100644
--- a/src/loaih/build.py
+++ b/src/loaih/build.py
@@ -570,8 +570,8 @@ class Build():
 
                 # We download the missing dependencies leveraging apt
                 subprocess.run(shlex.split(
-                    r"apt download " + debs.join(' ')),
-                    cwd=downloadpath, check=True)
+                    r"apt download " + str.join(" " , debs)
+                ), cwd=downloadpath, check=True)
 
                 # then we install them inside the AppDir
                 subprocess.run(shlex.split(