Ruby Developer Interview Preparation Guide
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Ruby Developer Frequently Asked Questions in various Ruby Developer job interviews by interviewer. The set of questions are here to ensures that you offer a perfect answer posed to you. So get preparation for your new job interview

74 Ruby Developer Questions and Answers:

1 :: Tell us what is class libraries in Ruby?

Class libraries in Ruby consist of a variety of domains, such as data types, thread programming, various domains, etc.

2 :: Tell me can you call a private method outside a Ruby class using its object?

Yes, with the help of the send method.

Given the class Test:

class Test
def method
p "I am a private method"
We can execute the private method using send:

"I am a private method"

3 :: Explain me what is the function of ORM in Ruby on Rails?

ORM stands for Object Relationship Model that models the classes and helps in setting a relationship between the existing models.


1. It allows the classes to be mapped to the table that is present in the database and objects get mapped to the rows in database table.

2. It shows the relationship that exists between the object and frame it using the model to display the output to the users.

3. It keeps the data in the database according to its relationships and performs the functions accordingly.

4 :: Tell me the role of modules and mixins in Ruby?

Modules are Ruby’s way of grouping methods, classes, and constants together to provide a namespace for preventing name clashes. The second purpose of modules is to use them as mixins. Technically, Ruby only supports single inheritance, but by using modules as mixins, it is possible to share code among different classes—a key advantage of multiple inheritance—without having to give up the simplicity of the single inheritance paradigm.

5 :: What is the difference extend and include?

The “include” makes the module’s methods available to the instance of a class, while “extend” makes these methods available to the class itself.

6 :: What is the syntax for Ruby collect Iterator?

The syntax for Ruby collect Iterator collection = collection.collect.

7 :: What is the difference between put and putc statement?

Unlike the puts statement, which outputs the entire string onto the screen. The Putc statement can be used to output one character at a time.

8 :: Tell me how can we define Ruby regular expressions?

Ruby regular expression is a special sequence of characters that helps you match or find other strings. A regular expression literal is a pattern between arbitrary delimiters or slashes followed by %r.

9 :: Tell us what is the difference between Dynamic and Static Scaffolding?

Dynamic Scaffolding:
It automatically creates the entire content and user interface at runtime
It enables to generation of new, delete, edit methods for the use in application
It does not need a database to be synchronized

Static Scaffolding:
It requires manual entry in the command to create the data with their fields
It does not require any such generation to take place
It requires the database to be migrated

10 :: Do you know what is rake in Rails?

Rake is a Ruby Make; it is a Ruby utility that substitutes the Unix utility ‘make’, and uses a ‘Rakefile’ and ‘.rake files’ to build up a list of tasks. In Rails, Rake is used for normal administration tasks like migrating the database through scripts, loading a schema into the database, etc.