Also, the employer may have policies and/or feelings about installing and/or running "unauthorized" software.
Trying to put myself in the employer's shoes, if I had one person who brought in their own tools, which allowed them to work at four times the usual rate, but refused to make the tools available to the rest of the company, I wouldn't be real happy wiith him. Mainly because it says loud and clear that he's more concerned with trying to make himself look good than with the company's success, and that's an attitude that wouldn't exactly thrill me.
If (as others have said) you actually own these lisps outright, you probably ought to offer to tweak the routines to tailor them to the company's needs, and sell or license those versions to the company. Or make programming part of your job description, with the understanding that what you write on the job is 100% oowned by the company.
IMHO you probably should have dealt with these issues before going on the payroll. As you have acknowledged, there is probably going to be some static over this. There are some ways to add a degree of protection to your files, in addition to compilation, but I think the first issues aren't going to be about programming.