Index: utils/objfw-new/NewClass.m
==================================================================
--- utils/objfw-new/NewClass.m
+++ utils/objfw-new/NewClass.m
@@ -70,13 +70,39 @@
 					 property.type, property.name];
 
 	if (properties.count > 0)
 		[headerFile writeString: @"}\n\n"];
 
-	for (Property *property in properties)
-		[headerFile writeFormat: @"@property %@%@;\n",
+	for (Property *property in properties) {
+		[headerFile writeString: @"@property "];
+
+		if (property.attributes.count > 0) {
+			bool first = true;
+
+			if ([property.attributes containsObject: @"nullable"])
+				[headerFile writeString:
+				    @"OF_NULLABLE_PROPERTY "];
+
+			[headerFile writeString: @"("];
+
+			for (OFString *attribute in property.attributes) {
+				if ([attribute isEqual: @"nullable"])
+					continue;
+
+				if (!first)
+					[headerFile writeString: @", "];
+
+				[headerFile writeString: attribute];
+				first = false;
+			}
+
+			[headerFile writeString: @") "];
+		}
+
+		[headerFile writeFormat: @"%@_%@;\n",
 					 property.type, property.name];
+	}
 
 	[headerFile writeString: @"@end\n"
 				 @"\n"
 				 @"OF_ASSUME_NONNULL_END\n"];
 

Index: utils/objfw-new/Property.h
==================================================================
--- utils/objfw-new/Property.h
+++ utils/objfw-new/Property.h
@@ -19,15 +19,17 @@
 OF_ASSUME_NONNULL_BEGIN
 
 @interface Property: OFObject
 {
 	OFString *_name, *_type;
+	OFArray OF_GENERIC(OFString *) *_attributes;
 }
 
 + (instancetype)propertyWithString: (OFString *)string;
 - (instancetype)initWithString: (OFString *)string;
 
 @property (readonly, nonatomic) OFString *name;
 @property (readonly, nonatomic) OFString *type;
+@property (readonly, nonatomic) OFArray OF_GENERIC(OFString *) *attributes;
 @end
 
 OF_ASSUME_NONNULL_END

Index: utils/objfw-new/Property.m
==================================================================
--- utils/objfw-new/Property.m
+++ utils/objfw-new/Property.m
@@ -15,19 +15,22 @@
 
 #include "config.h"
 
 #import "Property.h"
 
+#import "OFArray.h"
+#import "OFString.h"
+
 #import "OFInvalidArgumentException.h"
 #import "OFOutOfRangeException.h"
 
 @interface Property ()
 - (void)parseString: (OFString *)string;
 @end
 
 @implementation Property
-@synthesize name = _name, type = _type;
+@synthesize name = _name, type = _type, attributes = _attributes;
 
 + (instancetype)propertyWithString: (OFString *)string
 {
 	return [[[self alloc] initWithString: string] autorelease];
 }
@@ -46,16 +49,57 @@
 	return self;
 }
 
 - (void)parseString: (OFString *)string
 {
+	void *pool = objc_autoreleasePoolPush();
 	const char *UTF8String = string.UTF8String;
 	size_t length = string.UTF8StringLength, nameIdx = -1;
+	OFMutableArray *attributes = nil;
 
 	if (length > SSIZE_MAX)
 		@throw [OFOutOfRangeException exception];
 
+	if (UTF8String[0] == '(') {
+		for (size_t i = 0, level = 0; i < length; i++) {
+			if (UTF8String[i] == '(')
+				level++;
+			else if (UTF8String[i] == ')') {
+				if (--level == 0) {
+					OFString *attributesString = [OFString
+					    stringWithUTF8String: UTF8String + 1
+							  length: i - 1];
+					attributes = [[[attributesString
+					    componentsSeparatedByString: @","]
+					    mutableCopy] autorelease];
+
+					UTF8String += i + 1;
+					length += i + 1;
+
+					while (*UTF8String == ' ' ||
+					    *UTF8String == '\t') {
+						UTF8String++;
+						length--;
+					}
+
+					break;
+				}
+			}
+		}
+	}
+
+	for (size_t i = 0; i < attributes.count; i++) {
+		OFString *attribute = [[attributes objectAtIndex: i]
+		    stringByDeletingEnclosingWhitespaces];
+
+		[attributes replaceObjectAtIndex: i
+				      withObject: attribute];
+	}
+
+	[attributes makeImmutable];
+	_attributes = [attributes copy];
+
 	for (ssize_t i = (ssize_t)length - 1; i > 0; i--) {
 		if (UTF8String[i] == '*' || UTF8String[i] == ' ' ||
 		    UTF8String[i] == '\t') {
 			nameIdx = i + 1;
 			break;
@@ -66,10 +110,12 @@
 		@throw [OFInvalidArgumentException exception];
 
 	_name = [[OFString alloc] initWithUTF8String: UTF8String + nameIdx];
 	_type = [[OFString alloc] initWithUTF8String: UTF8String
 					      length: (size_t)nameIdx];
+
+	objc_autoreleasePoolPop(pool);
 }
 
 - (void)dealloc
 {
 	[_name release];