Even if your employment agreement doesn't say that, it might be advisable to sign an agreement with your employer that explicitly excludes any of your side proj

Even if your employment agreement doesn't say that, it might be advisable to sign an agreement with your employer that explicitly excludes any of your side projects that overlap with your employer's business. If it's linked enough to your employer's business, and you're salaried, and it could be demonstrated that it is part of your job duties, it might not be that clear as to who actually owns the code.