Pros
You are likely to make friends - unfortunately based on shared misery. If you are not on the radar of the CEO and have a strong team lead to protect you, you might have a reasonable working experience.
Cons
swissQuant is nothing like what you might hear during interviews. There is no leadership, there is no strategy, there is no plan, and while the CEO certainly thinks so, there is no excellence in quantitative finance. There is also no freedom to shape your role or the business, which you will learn quickly the first time your views are not aligned with the CEO. swissQuant can't decide whether it wants to be a software or a consulting firm, and given its constant struggle to survive, every opportunity to make a sale gets grabbed independently of whether it makes sense of not. This is also one of the main problems. Sales is everything and everything else gets sold out along the way. Everybody, and that is absolutely everybody, is expected to write contracts (the company has stopped long ago to send offers and just sends out contracts - typically displeasing the potential buyer) and sell. This obviously leads to frustration and despite the incredible staff turnover rate of 50-75!!! % per year, there is no correction, no change in behaviour, not the slightest bit of self-criticism. Much rather, the course that has led to the decline of the company is followed ever more vigorously. There is plenty of evidence of decline from shrinking company size, shrinking customer base, and not least, salary payments going out late regularly. Under no circumstances, should anyone take a leadership position in this company. The CEO has completely lost touch with reality, is unwilling to take advice and has absolutely unrealistic views and targets. However, from these delusional targets, he derives very concrete expectations which he pushes onto managers with great pressure - not that this has ever had any effect on improved sales. Equality, diversity and work experience are more areas where there is little light and much shadow. The atmosphere is based on mistrust, misinformation and controls. It is expected to be in the office (yes, home office is not appreciated) by 8 the very latest and walks around the entire office at this time and then again in the afternoon/evening to check staff presence are very common. Arguments such as nursery/school runs count for nothing.