If you have a scrambled cube and want to get it restored, just learn how to solve it. It might take a lot of time (especially if you've never solved a big cube before), but it's definitely not difficult.
If you want to generate algorithms for L2E cases or whatever, use ksolve.
If you have some other use case in mind, you probably should state that. (There aren't many situations other than the two above where you'd want a solver, but not to code it yourself.)