diff --git a/kenbuild/src/StartupWinController.m b/kenbuild/src/StartupWinController.m
index e8dcd533..f605a6b0 100644
--- a/kenbuild/src/StartupWinController.m
+++ b/kenbuild/src/StartupWinController.m
@@ -110,7 +110,7 @@ - (void)populateVideoModes:(BOOL)firstTime
         bpp  = settings->bpp3d;
         fullscreen = settings->fullscreen;
     } else {
-        fullscreen = ([fullscreenButton state] == NSOnState);
+        fullscreen = ([fullscreenButton state] == NSControlStateValueOn);
         mode3d = (int)[[videoMode3DPUButton selectedItem] tag];
         if (mode3d >= 0) {
             xdim = validmode[mode3d].xdim;
@@ -155,12 +155,12 @@ - (IBAction)fullscreenClicked:(id)sender
 
 - (IBAction)multiPlayerModeClicked:(id)sender
 {
-    [singlePlayerButton setState:(sender == singlePlayerButton ? NSOnState : NSOffState)];
+    [singlePlayerButton setState:(sender == singlePlayerButton ? NSControlStateValueOn : NSControlStateValueOff)];
 
-    [joinMultiButton setState:(sender == joinMultiButton ? NSOnState : NSOffState)];
+    [joinMultiButton setState:(sender == joinMultiButton ? NSControlStateValueOn : NSControlStateValueOff)];
     [hostField setEnabled:(sender == joinMultiButton)];
 
-    [hostMultiButton setState:(sender == hostMultiButton ? NSOnState : NSOffState)];
+    [hostMultiButton setState:(sender == hostMultiButton ? NSControlStateValueOn : NSControlStateValueOff)];
     [numPlayersField setEnabled:(sender == hostMultiButton)];
     [numPlayersStepper setEnabled:(sender == hostMultiButton)];
 }
@@ -187,17 +187,17 @@ - (IBAction)start:(id)sender
 
     settings->numplayers = 0;
     settings->joinhost = NULL;
-    if ([singlePlayerButton state] == NSOnState) {
+    if ([singlePlayerButton state] == NSControlStateValueOn) {
         settings->numplayers = 1;
-    } else if ([joinMultiButton state] == NSOnState) {
+    } else if ([joinMultiButton state] == NSControlStateValueOn) {
         NSString *host = [hostField stringValue];
         settings->numplayers = 2;
         settings->joinhost = strdup([host cStringUsingEncoding:NSUTF8StringEncoding]);
-    } else if ([hostMultiButton state] == NSOnState) {
+    } else if ([hostMultiButton state] == NSControlStateValueOn) {
         settings->numplayers = [numPlayersField intValue];
     }
 
-    settings->forcesetup = [alwaysShowButton state] == NSOnState;
+    settings->forcesetup = [alwaysShowButton state] == NSControlStateValueOn;
 
     if (inmodal) {
         [NSApp stopModalWithCode:STARTWIN_RUN];
@@ -206,27 +206,27 @@ - (IBAction)start:(id)sender
 
 - (void)setupConfigMode
 {
-    [alwaysShowButton setState: (settings->forcesetup ? NSOnState : NSOffState)];
+    [alwaysShowButton setState: (settings->forcesetup ? NSControlStateValueOn : NSControlStateValueOff)];
     [alwaysShowButton setEnabled:YES];
 
     [videoMode3DPUButton setEnabled:YES];
     [self populateVideoModes:YES];
     [fullscreenButton setEnabled:YES];
-    [fullscreenButton setState: (settings->fullscreen ? NSOnState : NSOffState)];
+    [fullscreenButton setState: (settings->fullscreen ? NSControlStateValueOn : NSControlStateValueOff)];
 
     if (!settings->netoverride) {
         [singlePlayerButton setEnabled:YES];
-        [singlePlayerButton setState:NSOnState];
+        [singlePlayerButton setState:NSControlStateValueOn];
 
         [hostMultiButton setEnabled:YES];
-        [hostMultiButton setState:NSOffState];
+        [hostMultiButton setState:NSControlStateValueOff];
         [numPlayersField setEnabled:NO];
         [numPlayersField setIntValue:2];
         [numPlayersStepper setEnabled:NO];
         [numPlayersStepper setMaxValue:MAXPLAYERS];
 
         [joinMultiButton setEnabled:YES];
-        [joinMultiButton setState:NSOffState];
+        [joinMultiButton setState:NSControlStateValueOff];
         [hostField setEnabled:NO];
     } else {
         [singlePlayerButton setEnabled:NO];
diff --git a/src/osxbits.m b/src/osxbits.m
index 0fa0d920..8998e302 100644
--- a/src/osxbits.m
+++ b/src/osxbits.m
@@ -58,7 +58,7 @@ int wmosx_filechooser(const char *initialdir, const char *initialfile, const cha
     [panel setDirectoryURL:initialdirurl];
 
     resp = [panel runModal];
-    if (resp == NSFileHandlingPanelOKButton) {
+    if (resp == NSModalResponseOK) {
         NSURL *file = [panel URL];
         if ([file isFileURL]) {
             *choice = strdup([[file path] UTF8String]);
@@ -69,5 +69,5 @@ int wmosx_filechooser(const char *initialdir, const char *initialfile, const cha
     [filetypes release];
     [initialdirurl release];
 
-    return resp == NSFileHandlingPanelOKButton ? 1 : 0;
+    return resp == NSModalResponseOK ? 1 : 0;
 }
diff --git a/xcode/engine.xcodeproj/project.pbxproj b/xcode/engine.xcodeproj/project.pbxproj
index 9a21723a..08c55277 100644
--- a/xcode/engine.xcodeproj/project.pbxproj
+++ b/xcode/engine.xcodeproj/project.pbxproj
@@ -989,7 +989,7 @@
 				);
 				GCC_WARN_PEDANTIC = YES;
 				HEADER_SEARCH_PATHS = "$(PROJECT_DIR)/../src";
-				MACOSX_DEPLOYMENT_TARGET = 10.9;
+				MACOSX_DEPLOYMENT_TARGET = 10.15;
 				ONLY_ACTIVE_ARCH = YES;
 				SKIP_INSTALL = YES;
 				WARNING_CFLAGS = (
@@ -1020,7 +1020,7 @@
 				);
 				GCC_WARN_PEDANTIC = YES;
 				HEADER_SEARCH_PATHS = "$(PROJECT_DIR)/../src";
-				MACOSX_DEPLOYMENT_TARGET = 10.9;
+				MACOSX_DEPLOYMENT_TARGET = 10.15;
 				SKIP_INSTALL = YES;
 				WARNING_CFLAGS = (
 					"-W",