Preference for all public-sector jobs (not just federal, but I think all fifty states give some forms of veterans preference, and a handful give “absolute preference” where a minimally-qualified veteran must be hired over a non-veteran regardless of qualifications.) But even where its not absolute preference, it often is a very strong preference (e.g., California on open civil service exams typically limits hiring to the top 3 ranks on the resulting hiring list, with each rank being 5 points of exam score on a 100-point, before preference points, scale. Veterans get 10 extra points, or 15 if they have a qualifying degree of disability.)