What is Ruby?
To begin with, let’s review what is Ruby itself. The Ruby programming language originated in the head of the Japanese programmer Yukihiro “Matz” Matsumoto. He wanted to create a new language that would balance functional and imperative programming. Striving for elegance and simplicity, the creator mixed pieces of his favorite languages such as Perl, Smalltalk, Eiffel, Ada and Lisp. Launched in 1995, Ruby gained mainstream acceptance in 2006. At the time, the main Ruby-Talk mailing list averaged 200 messages per day. In the following years, different groups opened up to discuss Ruby. Soon, groups of developers and programmers come together to form communities such as rubyonrails.com or the Ruby Community to share knowledge and extend existing libraries. Today, Ruby is one of the top ten most popular programming languages worldwide, largely due to its unique Ruby on Rails web framework.
Benefits of Ruby
First, the software license is completely free, and it’s also free to use, copy, modify, and redistribute. In addition to free customization and flexible features, Ruby offers many benefits for programmers and business owners.
“I needed a scripting language that was more powerful than Perl and more object oriented than Python.” This is what Matz said when he researched other programming languages in search of the perfect syntax. As a result, everything in Ruby is an object. To clarify, any piece of information and a line of code has its own properties and actions. From a technical point of view, in object-oriented programming, properties are called instance variables, and actions are called methods. Unlike other languages, a purely object-oriented approach can apply an action to numbers or various primitive types, opening up more possibilities for creation and web development.
As we mentioned earlier, Ruby is a flexible language because users can change; add; delete; and copy parts of it without restriction. For example, to improve the performance of a running project, a programmer might write the plus operator (+) or just the word plus. The same goes for numbers and other actions.
Ruby blocks are one of the features of this programming language. Using these types of blocks, the programmer can attach a closure (block) to any method, clearly illustrating the procedure. You can insert a block into a do… end construct, leaving room for additional details or new blocks to be filled in.
Unlike many object-oriented languages, Ruby is distinguished by having a single inheritance based on the concept of modules. Ruby classes can mix a module while getting other methods for free. As a result, Ruby authors can write complex and flexible code with a more explicit structure than multiple inheritance.
Ruby often uses limited punctuation in favor of English keywords. For these reasons, Ruby does not need variable declarations, but rather the pronunciation of words to indicate the scope of variables. Ruby has various implementations that can provide additional integration with other languages or environments. Here is a list of the most common:
JRuby is Ruby on top of the JVM (Java Virtual Machine) using the JVM’s optimizing JIT compilers, garbage collectors, parallel streams, an ecosystem of tools, and a vast collection of libraries.
TruffleRuby is a high performance implementation of Ruby on top of GraalVM.
mruby is a lightweight implementation of the Ruby language that can be bundled and built into an application.
IronRuby is an implementation “tightly integrated with the .NET Framework”.
MagLev is “a fast, stable implementation of Ruby with integrated object persistence and a distributed shared cache.”
Cardinal is “the Ruby compiler for the Parrot virtual machine” (Perl 6).
In addition to these skills, there is other information on a candidate’s resume that can show their competencies.
- Companies known for excellence
- Degree in Computer Science
- Good GitHub or other open source profile
- Books read by the candidate
- Knowledge of database queries
Interview questions for Ruby on Rails developers during phone/video technical interview
Once you have screened your resume, it may be helpful to make a primary telephone number. You shouldn’t drag out the conversation for too long, but it can tell you a lot about whether or not you should invite the candidate for an in-person interview. While they do not reveal exact programming skills, they can shed light on candidates’ understanding of the environment and their approach to technology.
Ruby on Rails interview questions
Question 1: What are the differences between Rails 4 and Rails 5?
Why you should ask: A management candidate or a candidate who claims to have been with Rails for over 2 years should know at least a couple of features added to Rails 5.
Question 2: Where do you write your logic in Ruby on Rails: models, views, or controllers? Is there an alternative?
Why you should ask this: “Fat model, thin controller” is the core motto of Ruby on Rails, so every Rails candidate should know this. However, higher level applicants should respond that they prefer Skinny Models, Skinny Controllers, and Fat Services.
Question 3: What is the main difference between rspec and minitest?
Why you should ask this: Tests are almost mandatory in Ruby. However, there are two great libraries for testing. A good candidate will know one of them, but a brilliant one will play with both, not just the one they use in their current position. They should be able to describe the main differences.
Question 4: Given a class that has these methods,
- def factorial(number): returns the factorial of #number
- def fibonacci(n): calculates the value of the nth fibonacci number
what unit test would you write?
Why you should ask this: Another test question, but in this case, in addition to testing their ability to write tests, the idea is to see how well the brainstorming candidate thinks about edge cases that might cause problems.
Question 5: You have code and you have tested it for a new feature on a new page. Immediately after deploying to production, we find that a new page is loading, but it takes one minute. What will you look at first?
Why you should ask this: This question isn’t specific to Ruby on Rails, but it will reveal a lot about your candidate and their experience with real-life problems. If the applicant is completely at a loss, he probably did not manage large projects. Also, the answer and the aspects it covers will tell you a lot about his experience with DevOps, JS, databases. The lead developer you’re looking for can tell you more than 5 places to look.
Question 6: Why did you choose Ruby on Rails?
Why you should ask: There are currently over a dozen frameworks to choose from, and it’s good to know which person applying for a Rails position started with that framework.
Question 6: What does Rails add to Ruby?
Why you should ask this: Although Ruby is very tied to Ruby on Rails, it’s good to know what are the additional benefits of frameworks and what is the core of the system.