From old to new: dealing with legacy software
A tricky problem is to deal with software legacy. I think I have never been anywhere where I did not need to deal with legacy some way or another. In fact my first task on my first job was to improve the performance of "old" design rule checker (DRC) by upgrading its geometric store with a KD-tree. That was during a summer job, and later as employee, I was asked to write a new DRC to replace the old one. (A DRC is used to check geometric rules in layouts of integrated circuits). The new DRC was better than the old one, and part of an automated layout tool for analog circuit, which... ultimatly failed. Commercially the project did break even, but other systems worked better. Looking back, with the hindsight of knowing which system succeeded, this CAD sytem failed to approach the problem the right way, which was incrementaly. For example, the requirements for the DRC were: do what the old software does but better and faster, yet they really should have been "make it incre...