I attended an event at a restaurant near Rapid7's Belfast premises, with several hundred graduates and approximately a dozen employees. The employees were mingling and taking notes on everyone they talked to.

Several months later their recruiter contacted me and said I was one of the attendees they were interested in. I met the recruiter for a half hour chat to discuss the position and my experience and skills and see if we were both still interested.

I had an interview a week or two later. There was a technical part, with two senior staff, and a discussion of my experience/motivation/etc with one senior, one recently hired graduate. Everyone I met was friendly and polite.

In the technical interview in particular, it came across clearly that they were interested in their work.

Code Fizzbuzz, in the language of your choice (or pseudocode).