In pretty much any software startup acquisition by a much larger company, even if they do technical due diligence up front they have to assume that all the code

In pretty much any software startup acquisition by a much larger company, even if they do technical due diligence up front they have to assume that all the code will need to be rewritten within a couple years. It's good to keep a few key technical resources around during the transition period but otherwise a high attrition level is acceptable.