diff --git a/setup.py b/setup.py
index 9c536a1..63e717c 100644
--- a/setup.py
+++ b/setup.py
@@ -10,7 +10,7 @@ opzioni = {
 	"app": ["Dropchat.py"],
 	"data_files": ["preferenze.json"],
 	"options": {},
-	"setup_requires": ["py2app"],
+	"setup_requires": [],
 }
 
 if sys.platform == "darwin":
@@ -18,6 +18,7 @@ if sys.platform == "darwin":
 		import py2app
 		sys.argv += "py2app",
 		opzioni["options"] = {"py2app": {"argv_emulation": False}}
+		opzioni["setup_requires"] += "py2app",
 	except ImportError:
 		exit("py2app non installato.")
 
@@ -26,6 +27,7 @@ elif sys.platform == "win32":
 		import py2exe
 		sys.argv += "py2exe",
 		opzioni["options"] = {"py2exe": {"bundle_files": 1, "compressed": True}}
+		opzioni["setup_requires"] += "py2exe",
 	except ImportError:
 		exit("py2exe non installato.")