Yes, a "rewrite" is the wrong way to think about this project. A typical programmer might be able to produce 10K lines of production code in a year, which means

Yes, a "rewrite" is the wrong way to think about this project. A typical programmer might be able to produce 10K lines of production code in a year, which means it would take 10,000 engineer-years to rewrite it all. The OP needs to think in terms of stewardship, not complete reconstruction, and make improvements by small steps as a gradual process. I talked about a similar problem here: http://short-sharp.blogspot.ca/2012/08/fixing-broken-codebase-part-i.html http://short-sharp.blogspot.ca/2012/08/fixing-broken-codebas...