Most common questions used in ROR interviews

I’m sure everyone has their own opinion and criteria to know what to ask and when to ask in a job interview specifically for Ruby on Rails developers. A friend of mine told me that some folks are more worried about syntax, clean code, object oriented design and patterns, those he said are very picky and sometimes you don’t want to work with them. Some tech leads I met told me that the good candidates should know HTTP, the differences between client and server, some of those leaders even said that they need to cool guys and love to program only.

I remember an interview for PHP position from 2005 for Softtek a mexican international software company, they asked me things like, what are differences between GET and POST, what are main changes from PHP 4 to PHP 5, and 10 more PHP language questions, but a girl asked me about MVC architecture and I was hmmm well no I don’t know. I still got the job.

In more interviews but now for Ruby on Rails, people asked me, so do you know how to create migrations and run rakes? what is the class used to map data with objects in rails? Do you know what is the difference between a view and a controller? What are the models used for?

Some others asked me, have you used TDD? what’s favorite TDD tool? do you know GIT? Can you explain me how a browser works? One really into details asked me how the stack of rails work? what is being used under the hood? One that almost everyone asks is what’s the most difficult task you faced and how did you solve it?

Some are silly, some are sillier, anyway, IMHO, I’d like to say that anything is granted, but you need to sure what kind of people do you require for the job, a doer, a solver, a super nerd programmer, an amazing ninja pirate 2.0 like some people says. Perhaps you need to take a few minutes to think about it and then decide what attributes you need to get the work done, what kind of relationship you want with this employee, co-worker, partner.

Given said that, I want to list a few of those questions that I remember the most and I’d like you to share more with me, thanks for reading:

1. What version of ruby on rails do you use?

2. What is Active Record?

3. How does MVC works in Rails?

4. What does CRUD mean?

5. Describe your git flow?

6. What is thin controller fat models?

7. What’s OOP?

8. What’s inheritance and polymorphism?

9. What is CDN?

10. List a few methods of Array class

11. List a few methods of String class

12. How do you debug your code in ruby on rails?

13. List 5 design patterns

14. How would use a helper in rails?

15. How does remote=true affects a link_to helper?

16. What is coffeescript?

17. What is the DOM?

18. What are the modules in ruby?

19. What is a gem?

20. Do you use RVM or Rbenv?

21. What are the migrations in rails?

22. How do you add indexes to your tables in rails?

23. When would you use standard active record relationships models to make a query and when not?

24. Can you describe how rack works in a rails app?


What is Active Record?
What is Bundler?
What is ORM?
Syntax of using session
Advantages of Ruby
What is MVC and what other languages uses it
How do you use Scafoldding (Ruby on Rails)
What is ORM?
Diference between Rails 2.2.2 (have you worked with this one?) vs older ones
What is the latest version of Rails?
What does Ruby support? single or multiple inheritance for the boot
What is gemfile.lock?
What is Structure method?
Use of load & require in Ruby?
Use of global variables in Ruby
Operators in Ruby
What kind of “conditions” Ruby supports?
What is garbage collection?
Difference between symbol & string in Ruby
Role of MVC arquitecture in RoR
Different type of association relationships that exists
What are the different components of Rails
Differences between procs and lambdas

What’s missing? What would you add?