Rebuilding the Social Security Administration’s Codebase - “Still, it’s interesting to think about how this should be done. I wonder if they could run the new system in a sandbox for a year, feeding it all the same inputs, and see whether it generates the same outputs.” // This feels like the kind of advantage government modernization projects have over commercial. There is not as much urgency. If the lifetime of a government agency and software is in centuries (we hope!), you can take a year to just run tests. Plus, you have an existing system to both compare to and keep the plane flying while you change the engines.