diff --git a/AppKit/CMakeLists.txt b/AppKit/CMakeLists.txt
index b875b293..dd06e61d 100644
--- a/AppKit/CMakeLists.txt
+++ b/AppKit/CMakeLists.txt
@@ -116,6 +116,8 @@ set(AppKit_sources
 	NSFontMetric.m
 	NSPoofAnimation.m
 	NSErrors.m
+	NSPopover.m
+	NSRunningApplication.m
 
 	nib.subproj/NSButtonImageSource.m
 	nib.subproj/NSNibBindingConnector.m
diff --git a/AppKit/NSApplication.m b/AppKit/NSApplication.m
index e11a5c8c..5747e607 100644
--- a/AppKit/NSApplication.m
+++ b/AppKit/NSApplication.m
@@ -55,6 +55,8 @@ NSString * const NSApplicationWillTerminateNotification=@"NSApplicationWillTermi
 
 NSString * const NSApplicationDidChangeScreenParametersNotification=@"NSApplicationDidChangeScreenParametersNotification";
 
+const NSAppKitVersion NSAppKitVersionNumber = 1504; // macOS 10.12
+
 @interface NSDocumentController(forward) 
 -(void)_updateRecentDocumentsMenu; 
 @end 
@@ -352,7 +354,7 @@ id NSApp=nil;
    [_applicationIconImage release];
    _applicationIconImage=image;
    
-	[image setName: @"NSApplicationIcon"];
+	[image setName: NSImageNameApplicationIcon];
 }
 
 -(void)setWindowsMenu:(NSMenu *)menu {
diff --git a/AppKit/NSImage.m b/AppKit/NSImage.m
index af4ce4a7..327fbc2b 100644
--- a/AppKit/NSImage.m
+++ b/AppKit/NSImage.m
@@ -19,6 +19,8 @@ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLI
 #import <Foundation/NSKeyedArchiver.h>
 #import <AppKit/NSRaise.h>
 
+NSImageName const NSImageNameApplicationIcon = @"NSApplicationIcon";
+
 // Private class used so the context knows the flipped status of a locked image
 // 10.4 does something like that - probably for more than just getting the flippiness - 10.6 uses some special NSSnapshotBitmapGraphicsContext
 @interface NSImageCacheView : NSView {
diff --git a/AppKit/NSPasteboard.m b/AppKit/NSPasteboard.m
index af06882e..ba2f5514 100644
--- a/AppKit/NSPasteboard.m
+++ b/AppKit/NSPasteboard.m
@@ -12,6 +12,7 @@ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLI
 
 NSString *const NSPasteboardTypeString = @"NSStringPboardType";
 NSString *const NSPasteboardTypePDF = @"NSPDFPboardType";
+NSString *const NSPasteboardTypePNG = @"NSPDFPboardType";
 NSString *const NSPasteboardTypeTIFF = @"NSTIFFPboardType";
 NSString *const NSPasteboardTypeRTF = @"NSRTFPboardType";
 NSString *const NSPasteboardTypeRTFD = @"NSRTFDPboardType";
diff --git a/AppKit/NSPopover.m b/AppKit/NSPopover.m
new file mode 100644
index 00000000..f7e10107
--- /dev/null
+++ b/AppKit/NSPopover.m
@@ -0,0 +1,20 @@
+#import <Foundation/NSObject.h>
+
+// DUMMY
+
+@interface NSPopover : NSObject
+@end
+
+@implementation NSPopover
+- (NSMethodSignature *)methodSignatureForSelector:(SEL)aSelector
+{
+	return [NSMethodSignature signatureWithObjCTypes: "v@:"];
+}
+
+- (void)forwardInvocation:(NSInvocation *)anInvocation
+{
+	NSLog(@"Stub called: %@ in %@", NSStringFromSelector([anInvocation selector]), [self class]);
+}
+@end
+
+
diff --git a/AppKit/NSRunningApplication.m b/AppKit/NSRunningApplication.m
new file mode 100644
index 00000000..0ee6f231
--- /dev/null
+++ b/AppKit/NSRunningApplication.m
@@ -0,0 +1,19 @@
+#import <Foundation/NSObject.h>
+
+// DUMMY
+
+@interface NSRunningApplication : NSObject
+@end
+
+@implementation NSRunningApplication
++ (NSMethodSignature *)methodSignatureForSelector:(SEL)aSelector
+{
+	return [NSMethodSignature signatureWithObjCTypes: "v@:"];
+}
+
++ (void)forwardInvocation:(NSInvocation *)anInvocation
+{
+	NSLog(@"Stub called: %@ in %@", NSStringFromSelector([anInvocation selector]), self);
+}
+@end
+
diff --git a/AppKit/NSWindow.m b/AppKit/NSWindow.m
index 2196a0e8..272df3db 100644
--- a/AppKit/NSWindow.m
+++ b/AppKit/NSWindow.m
@@ -49,6 +49,7 @@ NSString * const NSWindowWillCloseNotification=@"NSWindowWillCloseNotification";
 NSString * const NSWindowWillMoveNotification=@"NSWindowWillMoveNotification";
 NSString * const NSWindowWillStartLiveResizeNotification=@"NSWindowWillStartLiveResizeNotification";
 NSString * const NSWindowDidEndLiveResizeNotification=@"NSWindowDidEndLiveResizeNotification";
+NSString * const NSWindowWillBeginSheetNotification=@"NSWindowWillBeginSheetNotification";
 
 NSString * const NSWindowWillAnimateNotification=@"NSWindowWillAnimateNotification";
 NSString * const NSWindowAnimatingNotification=@"NSWindowAnimatingNotification";
diff --git a/AppKit/include/AppKit/NSApplication.h b/AppKit/include/AppKit/NSApplication.h
index 200ceb3e..6c66525b 100644
--- a/AppKit/include/AppKit/NSApplication.h
+++ b/AppKit/include/AppKit/NSApplication.h
@@ -36,6 +36,8 @@ APPKIT_EXPORT NSString *const NSApplicationWillTerminateNotification;
 APPKIT_EXPORT NSString *const NSApplicationDidChangeScreenParametersNotification;
 
 APPKIT_EXPORT id NSApp;
+typedef double NSAppKitVersion;
+APPKIT_EXPORT const NSAppKitVersion NSAppKitVersionNumber;
 
 typedef id NSModalSession;
 
diff --git a/AppKit/include/AppKit/NSImage.h b/AppKit/include/AppKit/NSImage.h
index f73ccb3a..3a600ee6 100644
--- a/AppKit/include/AppKit/NSImage.h
+++ b/AppKit/include/AppKit/NSImage.h
@@ -123,3 +123,9 @@ typedef enum {
 @interface NSBundle (NSImage)
 - (NSString *)pathForImageResource:(NSString *)name;
 @end
+
+typedef NSString* NSImageName;
+
+APPKIT_EXPORT NSImageName const NSImageNameApplicationIcon;
+// TODO: A ton of other defined image names
+
diff --git a/AppKit/include/AppKit/NSPasteboard.h b/AppKit/include/AppKit/NSPasteboard.h
index 567882e1..4fb2a99c 100644
--- a/AppKit/include/AppKit/NSPasteboard.h
+++ b/AppKit/include/AppKit/NSPasteboard.h
@@ -12,6 +12,7 @@ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLI
 // New Pasteboard Types (added in 10.6) and interchangeable with the old pasteboard types in Cocotron
 APPKIT_EXPORT NSString *const NSPasteboardTypeString;
 APPKIT_EXPORT NSString *const NSPasteboardTypePDF;
+APPKIT_EXPORT NSString *const NSPasteboardTypePNG;
 APPKIT_EXPORT NSString *const NSPasteboardTypeTIFF;
 APPKIT_EXPORT NSString *const NSPasteboardTypeRTF;
 APPKIT_EXPORT NSString *const NSPasteboardTypeRTFD;
diff --git a/AppKit/include/AppKit/NSWindow.h b/AppKit/include/AppKit/NSWindow.h
index ae1903c5..ae7a234c 100644
--- a/AppKit/include/AppKit/NSWindow.h
+++ b/AppKit/include/AppKit/NSWindow.h
@@ -100,6 +100,7 @@ APPKIT_EXPORT NSString *const NSWindowDidUpdateNotification;
 APPKIT_EXPORT NSString *const NSWindowWillCloseNotification;
 APPKIT_EXPORT NSString *const NSWindowWillStartLiveResizeNotification;
 APPKIT_EXPORT NSString *const NSWindowDidEndLiveResizeNotification;
+APPKIT_EXPORT NSString *const NSWindowWillBeginSheetNotification;
 
 @interface NSWindow : NSResponder {
     NSRect _frame;