diff --git a/GTObservable.xcodeproj/project.pbxproj b/GTObservable.xcodeproj/project.pbxproj
index 5204bf2..8cd933d 100644
--- a/GTObservable.xcodeproj/project.pbxproj
+++ b/GTObservable.xcodeproj/project.pbxproj
@@ -244,6 +244,7 @@
 		6FD8524C1E7C597600ECCEEE /* Debug */ = {
 			isa = XCBuildConfiguration;
 			buildSettings = {
+				APPLICATION_EXTENSION_API_ONLY = YES;
 				CLANG_ENABLE_MODULES = YES;
 				CODE_SIGN_IDENTITY = "";
 				DEFINES_MODULE = YES;
@@ -265,6 +266,7 @@
 		6FD8524D1E7C597600ECCEEE /* Release */ = {
 			isa = XCBuildConfiguration;
 			buildSettings = {
+				APPLICATION_EXTENSION_API_ONLY = YES;
 				CLANG_ENABLE_MODULES = YES;
 				CODE_SIGN_IDENTITY = "";
 				DEFINES_MODULE = YES;