In Germany, the job of a scientist for the public sector is regulated in a way that
- on time limited contracts which are the general case you can work at most 6 years before achieving your PhD and at most 6 after it (Wissenschaftszeitvertragsgesetz) and then only on permanent contracts (extremely rare) or under very special circumstances;
- your payment follows a fixed payment agreement framework (TVÖD).
Are there comparable regulations in US?