Behavioural interviews take a look at your "personality", and consider things like how you can work in a team, what is your general attitude to work, and so on. It's hard to pinpoint the exact definition for these types of the interview, but you may get asked questions like "What was the most challenging project you worked on and why?" and "What was your biggest failure during the time at company X?". These interviews also differ greatly from company to company.
Behavioural interviews are sometimes separate rounds of interviews, but it's also common to get similar questions during the coding rounds. For example, you may be asked to "briefly describe your previous experience", or just to "introduce yourself".
It's hard to say how exactly your behavioural interviews will look and how to prepare. But let's try and break down some approaches:
- Understand how behavioural interviews are done and what is the format.
- Think about what interviewers are looking for.
- List common questions you may be asked, and prepare answers in advance.
For a great introduction on the behavioural interviews, how they are done and what interviewers are looking for, watch this video by Jackson Gabbard:
It's also probably easier to list red flags that the interviewers are looking for. Be aware of them:
- Be honest. Interviewers often can see when you lie or not being completely honest. This is a huge red flag, as this questions your integrity. Telling the truth, even if it's not the most flattering, is always the best approach (this probably extends beyond the behavioural interviews as well).
- Don't blame others. Blaming or criticizing others is also a red flag. Focus on yourself. If some mistakes happened, think about what you or your team as a whole could have done, but don't try to cover it up by shifting the blame to others.
- In general, be a positive and kind person :)
"Tell me about yourself", or "Describe your previous experience", or "Please, introduce yourself" are very common behavioural-style questions. They often appear in the usual coding rounds as well, just to break the ice before solving problems, and to allow your interviewer to know you better.
What should your answer look like? Don't make it too long, but don't keep it too short as well. Three-five short, but clear sentences will do. Talk about relevant things: where do you work right now? what are you looking for in the future? what is your experience? An example of a good answer can be something like:
My name is X, and currently I am a backend engineer at company Y. I've been at this company for three years, and was mostly working on payment systems. Before that I was for two years at company Z working on messaging services, and before that I graduated from college C.
Currently I am looking for backend positions at some bigger tech companies, just like [company you are interviewing for].
Don't worry about the answer too much, but keep it relevant and short. Your goal is not really to impress interviewer about something, but to simply introduce yourself in a fashion that shows how your background is relevant to the position you are interviewing for.
Often during behavioural interviews you are also discussing your background and basically everything that's written in your resume.
You are expected to be able to go in depth on your past experience, and extensively explain your past projects and roles. This will show that you really understand everything that's written on your resume, and that you can communicate it well.
To prepare, the first step is not to include too much on your resume, and definitely not to include projects you really haven't been working on much. You should stand behind everything you are claiming to have done, and be able to explain it well.
Review your past experience and projects to be ready. What have you done? What have you learned? What were the difficulties?
Here are some more good resources to prepare for behavioural interviews. Specifically, write down common questions you may be asked, and prepare your answers in advance.
- Read a behavioural interviews chapter in Cracking the Coding Interview.
- Good list of behavioral questions.
- Communication: how to be a better software developer.