Hi, I have been trying to use the NSDate initWithTimeInterval:sinceDate: method to measure elapsed times. I know there has been some discussion about the mapping from Cocoa NSDate to Ruby Time and back but I'm not sure if this is supposed to be working now? Here's a snip of code that calculates the interval using Ruby Time and then NSDate #!/usr/local/bin/macruby puts "Ruby Version: #{RUBY_VERSION}, MacRuby Version: #{MACRUBY_VERSION}" puts "\n\nRuby vesion - works as expected" point_in_time = Time.now puts "Ruby start time #{point_in_time}" sleep(1) later_time = Time.now puts "Later time: #{later_time}, interval: #{later_time - point_in_time} seconds" puts "\n\nFailing Cocoa version" cocoaTime = NSDate.date puts "Coca start time: #{cocoaTime}" sleep(1) cocoaFinishTime = NSDate.date puts "Cocoa Later time: #{cocoaFinishTime}, interval: #{cocoaFinishTime.timeIntervalSinceDate( cocoaFinishTime)} seconds" And here's the output, note the NSDate sees zero intervale... Ruby Version: 1.9.2, MacRuby Version: 0.8 Ruby vesion - works as expected Ruby start time 2011-02-13 16:33:23 +0000 Later time: 2011-02-13 16:33:24 +0000, interval: 1.000694 seconds Failing Cocoa version Coca start time: 2011-02-13 16:33:24 +0000 Cocoa Later time: 2011-02-13 16:33:25 +0000, interval: 0.0 seconds User error? or do I need to file a ticket? Best wishes and thanks, Jonathan