Rails is a development tool for web developers that gives them a framework structure for all the code. The Rails framework helps them to build websites and applications by simplifying repetitive tasks.
Rails is written in a programming language called Ruby, and hence the name Ruby on Rails (ROR). Every business has an online presence to boost sales and target more customers in today’s world.
So, from e-commerce store web designers to gaming programmers to facebook api developers for hire, every sector needs Ruby on Rails programmers. But, for a recruiter, what is the secret for selecting the best developer for your firm?
Top Questions to Test ROR Developers
What Is Object-Oriented Programming? What are some aspects of it?
Since the framework is written in Ruby, the candidates should be well-versed in the language, since it relies heavily on object-oriented programming (OOP).
Class hierarchies, encapsulation, inheritance, and polymorphism are essential concepts that every ROR web developer should know. If necessary, you can ask to write a sample code for a class or any OOP concept or just a verbal answer.
This question is the most basic interview question for a ROR developer. If you see them fumbling here, the interview practically ends here.
What is the latest version of Rails as well as Ruby? How is it an improvement from the earlier one?
Although the question is theoretical, it tests the candidate’s general awareness of the Ruby language and the Rails framework. This knowledge may not be directly relevant to the project.
However, the candidate should know how developers elsewhere are improving the language so that they can stay-up-to-date and incorporate all the latest tools in your project. As of May 2020, the latest stable release is version 6.0.3.1.
Write a Rack application.
Rack is a commonly used interface for programmers to develop an application in Ruby. Every programmer you hire must be proficient in writing code and not just understanding the concepts.
Within the limited time of an interview, asking the candidate to demonstrate a simple application in Rack is a quick test of their coding skills.
You can also ask some theoretical questions about some aspects of the Rack interface, Middleware stack, or any other relevant thing.
What is the structure and purpose of a RubyGem?
RubyGems is a package manager for the Ruby language that gives a standard format for distributing programs and libraries, in a self-contained template called a “gem.”
Irrespective of the application you want to hire a developer for, they will surely use multiple gems during the project. The candidate’s knowledge of RubyGems’ basic structure will give you confidence that they know where and how to get the necessary help.
Explain the algorithm or syntax of a particular code snippet.
This question is connected to the last one since both tests how well a developer can understand others’ codes. The RubyGems repository contains codes for various applications by programmers worldwide, of which some could be useful for your work.
To use the code that someone else has already written – thereby saving plenty of time – the developer must understand code snippets.
This skill is useful because different versions of Ruby could have slight variations in syntax and language. A developer should be able to take the idea from one code and change it according to another version’s syntax.
What are the best ways to secure data, such as a password?
Of late, a concern for everyone who uses the internet in any name or form is security. As a Ruby on Rails developer, the candidate must know all the existing methods of protecting data over the internet and what security measures are suitable for what situations.
Security-related questions can be generic (why should one use HTTPS instead of HTTP) or specific to ROR (Describe an XSS/Cross-Site scripting attack).
What are your preferred tools for writing unit tests and feature tests?
Traditionally, developers build the code, and a quality assurance (QA) team takes responsibility for testing the code. Today, the trend is for developers to run automated tests on their code, following the testing guidelines and best practices.
Your web development team would no longer need a redundant QA team if the ROR developer you hire is familiar with the various tests and tools available.
What is the Model-View-Controller approach to building applications?
Rails has an application directory called app/ with three sub-directories: models, views, and controllers. Together, they form the MVC approach, which separates an application’s data, user interface, and control logic.
This concept is a USP or sorts to ROR, so your developer should be familiar with the MVC approach and related technicalities.
What are the best practices for refactoring code?
Writing code is a skill, but writing elegant and efficient code is an art. Developers must continuously improve their code to make it more readable, faster, and easily modifiable based on client requests.
Code bugs in Ruby are called “code smells.” There are several bug detectors like Reek that come in handy for developers. You can test your candidate on their knowledge of refactoring tools and practices.
Give them a take-home assignment involving a problem statement.
There are only a given number of things you can test in an interview room within 20 minutes. As a final shortlisting stage, it is good to give the candidate a take-home assignment in the form of a problem statement, probably something your company is facing.
You can make it open-book and announce a deadline to submit since this is how the situation would be if or once you hire them.
May the Best Developer Win
It can be quite challenging to hire ruby on rails developer, especially when there are so many candidates with varying levels of expertise and professionalism.
The ten questions given here are by no means exhaustive, nor is it necessary that you ask all of them to every candidate. Ultimately, you need to use your judgment as an interviewer to pick the right candidate with the best mix of ethics, personality, and of course, skill.