As you get to the end of your interview, you have three crucial steps:
Ask final questions.
Ask for the job.
Ask for next steps.
The interviewer will probably ask whether you have any other questions. Go through your list, and ask those that you haven’t been able to ask conversationally. If all the questions have been answered, then briefly recap what they were as go through the list to show that you did indeed bring questions with you.
Let’s see…we talked about the network infrastructure…talked about how I would be allowed to work on open source projects…reporting structure…no, that about covers it, thanks.
Now you must ask for the job, explicitly. It may feel awkward to do this ...