One of my first jobs in the industry was really similar. I ended up sitting down with a friend and rewriting it in C#. We didn’t have permission, but no one knew until our codebase was already in working shape (a month or so). We got away with it because the original codebase was so bad that it hadn’t shipped in 5 years. Months of 0 productivity were normal. My friend and I went on to rewrite the entire suite of products over the course of a year or two. We then started our own business. The rewrites were the most successful products that company had ever had in the modern era. Rewriting is not always a bad idea, and it can be less expensive in the medium run. Few seem to realize this, thanks to Joel Spolsky’s blog post on the matter being seen as dogma.
We had a bunch of code at work that everyone sort of begrudgingly used that I wrote almost 20 years ago, not knowing too much about what I was doing. I have recently rewritten it – about 100kLOC of messy C++ turned into 25kLOC of bliss. The test coverage we had ensured that we didn’t have to worry about anything breaking. I hate myself a bit less :)
