Personio's Madrid office is an interesting one. I've never worked in a company so full of politics, gossips and backstabbing between colleagues. In this office, there are no friends, you cannot really trust anyone.
The product team seem to believe they are above anyone else in the company so because of this they should be treated better, have better benefits and earn more. If you are a woman or you are earning more than them, you have a problem: this people will bully you, plot and gossip behind your back, making your life difficult until you are forced to leave.
To be honest, too much time is wasted in gossiping and plotting instead of doing the actual work. No wonder why the new Payroll product they are trying to build is full of bugs and issues and customers seem to prefer the competition.
During my time there, I felt I was back in High School rather than working in a fast paced tech startup. It seems more important to show off you are working long hours than factual numerical results.
There is no team work, some people won't share their work and won't share all the important information needed for the team to succeed. These people seem to believe keeping some info for themselves will give them some sort of power and could make them look better in front of management. Under my perspective, these people are just full of insecurities and are immature. Because of the lack of trust culture they also work in, I want to believe all they are trying protecting their own job.
I don't believe this is a place where a good candidate could grow and even try to have an impact.
All of the above is blocking success and employee development, so I wouldn't recommend it if what you want is a place to stay for long, with a good business strategy and where you can have an impact. At least not in the Madrid office where 5 people resigned during the time I was there (less than a year); some of them due to a burnout and bullying.