During development phase its very easy to cross the design boundary – we want to take care about all possibilities and potential changes that can happen in our project. On the other hand when we are under the time pressure we take shortcuts which could in the end increase cost of even simple changes. How to deal with “overdesign”? How (at the same time) don’t close for improvements and changes? When we should make crucial technical decisions and when accept technical debt? This session is about true stories, mostly about huge mistakes, but also sometimes about decisions which in the end were very successful. The session for all who don’t want to end up with project that need’s to be rewritten to add a new button. The session for all who cares.