Postgresql installation, avoid creating “postgres” user I have a constraint, that I can use only one user on a SUSE Linux Enterprise Server 11.

Now, I need to install PostgreSQL 9.4. Is it possible to somehow avoid the automatic creation of "postgres" linux user by PostgreSQL's installation wizard, and use current user as a database admin?

Additional explanation about the weird  constraints:

We have to host our software on the server of the IT company, which is subsidiary of the big bank. They have quite strict rules, due to storing and processing of the sensitive user data. So, one of the rules, is that we can have only one user there and everything should be installed under this user (with sudo rights). Initially, the server has only the most basic software (and PostgreSQL is not included there).
The full answer is in this post: https://serverfault.com/questions/929677/postgresql-installation-avoid-creating-postgres-user

The only way is to build PostgreSQL from source.