First of all, I want to thank Contentsquare team for the exciting and challenging interviews. I definitely recommend it :)
What follows is an overview of the interviews I passed + some personal recommendations/advice.
1. HR phone screen:
Present yourself? don't tell your life story, concentrate on what value could you bring to the company.
Tell me about a challenging experience? show them your creative side by demonstrating the process and the methodologies that you've gone through to solve real life problems.
What Technologies are you familiar with? choose between those mentioned in the job description, and be prepared to talk about related experiences.
Why do you want to join Contentsquare? if you are really interested in the company, you have to invest time in reading about their history and their recent funding, their engineering blogs and case studies (on their website), you can also watch their YouTube videos, ...
What are your salary expectations?
2. Behavioural & technical interview (one interviewer)
Present yourself? again, don't tell your life story.
Demonstration of Contentsquare product: be sure to ask the interviewer good relevant questions.
Tell me about a good (challenging) and a bad (with conflicts & mistakes) experience? have a look at "Cracking the coding interview" book in order to ace this tricky question.
Clean code related questions: mainly about SOLID, but you can talk about other clean code principles like KISS, DRY, YAGNI, ...
30mn live Coding test: array manipulation, approach it with TDD to get bonus points.
3. Behavioural & technical interview (two interviewers)
Present yourself? ...
Tell me about a challenging experience? ...
General software engineering questions: OOP, design patterns (GOF and architectural), data structures, web app architecture (DNS, CDN, load balancers, web servers, microservices, microfrontends, MVC, databases ...), authentication types ... Be sure also to prepare javascript vs typescript and some advanced topics of Javascript like event loop, closures, async vs sync, server side (nodejs) vs client side, ... CI/CD, Gitflow
As you noticed, they will ask you a lot of technical questions, so be prepared to answer questions you don't know the answer (you can ask clarifying questions and/or talk about related concepts, ...)
30mn live coding test: array manipulation, begin by providing a brute force solution, than try to optimize it.
Personal recommendation:
Answer behavioural questions using the STAR technique.
Carefully read the ppt presentation of contentsquare that you will receive by email.
Write follow up emails after each interview to give your own feedback.
Communicate well (practice at home and do mock interviews with your friends)
Read "Cracking the coding interview" book by Gale Laakmann McDowell and Clean Code book by Robert c. Martin
Good luck :))