Blip (Portugal) Backend Engineer Interview Questions
& Process

Too many technical interviews. Take home assignment and two additional technical calls on top of the culture fit call and HR screenings. It takes a long time to get through the process.

First, there was an HR screening that lasted about 30 minutes. Then, I did a devskiller test which included general OO questions, common Java interview questions on topics like Containers, a code-review of a small program, filling in another small program, and developing one program under time constraints, lasting about 1.5 hours. After that, I had a technical interview with some devs from the area, covering general background questions, my technical experience, and general OO questions, lasting about 1 hour. Finally, I had an interview with 2 other devs where we reviewed the devskiller test, discussed general OO/Java questions such as immutability, and did 2-3 live coding exercises, followed by a follow-up interview with HR/PM.

This was a pretty good interview, but the company is really demanding and the process is long. My experience had 4 stages. First, a 30-minute call with HR. Then, a Devskiller test with multiple-choice questions on OOP and Java topics like Garbage Collector and design patterns, plus a simple coding exercise. After that, a 45-minute technical interview with 2 developers where we discussed my background and then they asked a lot of questions about OOP and Java concepts like access modifiers, synchronization, Java collections, and immutability. Finally, a 2-hour technical interview with 2 developers (one was observing) covering my previous experience and more Java/OOP questions for about an hour. Then, a practical coding problem where I had to analyze time and space complexity, which wasn't too hard. The trickiest part was a system design question. The interview ended with another 30 minutes with HR for social questions. Despite the length and number of stages, the staff was friendly and it wasn't overly difficult.