The whole process can be unprofessional. First, they allow people to be identified as alien during the application process, which is unbecoming of the government sector. Secondly, there were so much red tape just from applying. For example, there were 3 forms to fill up (which could be done in 1 setting, but no, they only send you the second form after the first is completed, an inefficient process). Thirdly, the interview can be very judgemental and indecorous.
Went for interview and they ask questions about national service, what I did and my PES status. As I like the structure of the job, I took the initiative to learn more about the company, including how it procure things. Was confident in my interview and shared what I know about it, even finding out the latest news. But when they ask me if I have any questions, I asked some questions related to the role on the website and some clarification on their procurement process. The response I received was "why you want to know?" for every questions I ask. Honestly if you ain't keen to let me ask questions, just say so. There is no need to assume that people has some ulterior motives for taking the initiative to learn more about the company. In fact, the panel, including the director doesn't even know what's on the company website and struggled to answer my questions. After that, they were quick to chase me out and I received the update that I was not selected in a few days for knowing too much and I pose a threat to them because of my lower PES status due to a minor surgery I underwent when I was 6 years old.
Also, based on my research and asking people working in DSTA, note that there is limited ability to progress in the job, but it can be a good as a stepping stone. Even when there is promotion, you are basically still doing the same thing but no pay increment.