Contractors are generally paid to solve a problem, and you'll be hard pressed to find an employer that believes tchnical.debt is worth paying boat loads of money for. If this is your angle of interest, I'd look into "legacy modernization", which works in a lot of the same ways as code refactoring with the big difference that you generally also need to shift programming languages and computing platforms . I did a gig 10 years ago and learned enough Cobol to be competent but most of the work was learning the business domain, format shift code, refactor over and over.