Neither the City of Round Rock nor the State of Texas require a general business or occupational license/permit. There are, however, state regulatory entities that require a license or permit related to the type of business service or product that you provide.
The Texas Department of Licensing and Regulation is prepared to answer any license or permit questions and provides a list of requisite occupations on their website.
Texas Department of Licensing and Regulation – Main Office
Austin, Texas 78701
512.463.6599 or 800.803.9202