Hr is notoriously difficult to get ahold of. They offer the base salary. Bonuses are usually difficult or impossible to get. In the best projects, you'll be bored with not much to do, feeling like a number in a spreadsheet, easily replaceable by anyone. In the worst projects, the conditions are dystopian, offering you little to no time off the computer, rolling shifts that make life almost unbearable. Housing is fine, but there is little care to fixing issues between flatmates, which are the most common.
Only apply if you have no better prospects. Do not assume that you will ever be respected by the company or your superiors. You will always be treated as disposable, and with suspicion. There is no benefit in growing within the company.