[hiddencost]

If you sell it you'll have to commit to maintaining it.

Typically the marginal value of a better job in software dwarfs the revenue you could make from selling software.

"Applied Computing Technology" is not something I've ever heard of, however. It's a bit hard to give advice, because I can't tell what kinds of jobs you might be likely to get; going 4 years between degree and job suggests that your options might be somewhat limited. Having evidence of successful open source projects might make you stand out.