diff --git a/NetNewsWire.xcodeproj/project.pbxproj b/NetNewsWire.xcodeproj/project.pbxproj
index 23535d353..ab787fb75 100644
--- a/NetNewsWire.xcodeproj/project.pbxproj
+++ b/NetNewsWire.xcodeproj/project.pbxproj
@@ -2798,6 +2798,7 @@
 			buildSettings = {
 				ALWAYS_EMBED_SWIFT_STANDARD_LIBRARIES = NO;
 				CODE_SIGN_ENTITLEMENTS = "Safari Extension/Subscribe_to_Feed.entitlements";
+				ENABLE_HARDENED_RUNTIME = YES;
 				INFOPLIST_FILE = "Safari Extension/Info.plist";
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/../Frameworks @executable_path/../../../../Frameworks";
 				PRODUCT_BUNDLE_IDENTIFIER = "com.ranchero.NetNewsWire-Evergreen.Subscribe-to-Feed";
@@ -2812,6 +2813,7 @@
 			buildSettings = {
 				ALWAYS_EMBED_SWIFT_STANDARD_LIBRARIES = NO;
 				CODE_SIGN_ENTITLEMENTS = "Safari Extension/Subscribe_to_Feed.entitlements";
+				ENABLE_HARDENED_RUNTIME = YES;
 				INFOPLIST_FILE = "Safari Extension/Info.plist";
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/../Frameworks @executable_path/../../../../Frameworks";
 				PRODUCT_BUNDLE_IDENTIFIER = "com.ranchero.NetNewsWire-Evergreen.Subscribe-to-Feed";
@@ -3252,6 +3254,7 @@
 			buildSettings = {
 				ALWAYS_EMBED_SWIFT_STANDARD_LIBRARIES = NO;
 				CODE_SIGN_ENTITLEMENTS = "Safari Extension/Subscribe_to_Feed.entitlements";
+				ENABLE_HARDENED_RUNTIME = YES;
 				INFOPLIST_FILE = "Safari Extension/Subscribe-to-Feed-MAS-Info.plist";
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/../Frameworks @executable_path/../../../../Frameworks";
 				PRODUCT_BUNDLE_IDENTIFIER = "com.ranchero.NetNewsWire-Evergreen.mas.Subscribe-to-Feed";
@@ -3267,6 +3270,7 @@
 				ALWAYS_EMBED_SWIFT_STANDARD_LIBRARIES = NO;
 				CODE_SIGN_ENTITLEMENTS = "Safari Extension/Subscribe_to_Feed.entitlements";
 				CODE_SIGN_IDENTITY = "3rd Party Mac Developer Application";
+				ENABLE_HARDENED_RUNTIME = YES;
 				INFOPLIST_FILE = "Safari Extension/Subscribe-to-Feed-MAS-Info.plist";
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/../Frameworks @executable_path/../../../../Frameworks";
 				PRODUCT_BUNDLE_IDENTIFIER = "com.ranchero.NetNewsWire-Evergreen.mas.Subscribe-to-Feed";