20 Elixir Interview Questions and Answers

Elixir is a functional, concurrent, general-purpose programming language that runs on the BEAM virtual machine. Elixir is used in web development, system administration, embedded programming, and much more. If you’re interviewing for a position that requires Elixir skills, you’ll want to be prepared to answer questions about the language. In this article, we’ll go over some of the most common Elixir interview questions so you can ace your next interview.

Elixir Interview Questions and Answers

Here are 20 commonly asked Elixir interview questions and answers to prepare you for your interview:

1. What is Elixir?

Elixir is a functional, concurrent, general-purpose programming language that runs on the Erlang virtual machine.

2. What are some of the main features of Elixir?

Some of the main features of Elixir include its focus on functional programming, its use of the actor model for concurrency, and its support for metaprogramming.

3. What is functional programming and how does it relate to Elixir?

Functional programming is a programming paradigm that emphasizes the use of functions and immutable data. This can be contrasted with imperative programming, which emphasizes the use of side effects and mutable data. Elixir is a functional programming language that runs on the Erlang virtual machine.

4. How do you run an elixir program?

You can run an elixir program by using the elixir command followed by the path to the program. For example, if your program is called my_program.exs, you would run it by typing elixir my_program.exs at the command line.

5. Is Elixir a compiled or interpreted language? What kinds of languages are compiled and which ones are interpreted?

Elixir is a compiled language. This means that it is converted into machine code before it is executed. This is in contrast to interpreted languages, which are read and executed line by line by a program called an interpreter. Compiled languages tend to be faster and more efficient than interpreted languages.

6. Can you explain what Erlang is?

Erlang is a functional programming language that was originally designed for telecom applications. It is known for its scalability and its ability to handle large numbers of concurrent connections.

7. What’s the difference between Elixir and Erlang?

Elixir is a functional, concurrent, general-purpose programming language that runs on the Erlang virtual machine. It was designed to improve upon some of the shortcomings of Erlang, such as its syntax and lack of metaprogramming support.

8. Can you give me some examples of real-world applications that use Elixir?

There are many real-world applications that use Elixir, including:

-The popular chat application Slack is written in Elixir.
-The programming language Ruby on Rails uses Elixir for its web server.
-The video game Overwatch uses Elixir for its matchmaking system.

9. What are some best practices for using Elixir in production?

Some best practices for using Elixir in production include:

– Use a tool like Distillery to create releases for your Elixir applications. This will allow you to package your application with all of its dependencies, and will also allow you to manage different application environments (e.g. development, staging, production) more easily.

– Use a tool like ExUnit to write comprehensive tests for your Elixir code. This will help ensure that your code is working as expected, and will also make it easier to refactor code or add new features later on.

– Use a tool like Phoenix to build web applications. Phoenix is a high-performance web framework that is built on top of Elixir, and provides many features out of the box that can make development faster and easier.

10. What is OTP?

OTP is a set of Elixir libraries that provide a framework for building concurrent, fault-tolerant, and distributed applications.

11. What do you understand about pattern matching in Elixir?

Pattern matching is a feature of the Elixir programming language that allows developers to easily and concisely match data against patterns. This can be used to destructure data, perform operations on data, and more. Pattern matching is a powerful tool that can greatly simplify code.

12. What are some different types of variables available in Elixir?

There are four different types of variables available in Elixir: atoms, strings, integers, and floats. Atoms are immutable and can be used as identifiers. Strings are also immutable and can be concatenated. Integers are whole numbers and can be used for mathematical operations. Floats are numbers with decimal points and can also be used for mathematical operations.

13. Can you explain what macros are and when they can be used?

Macros are a way to extend the Elixir language with custom functionality. They are written in Elixir and are compiled at compile-time. Macros can be used to define new syntax, optimize code, and more.

14. Can you explain what immutable data structures are and why they’re important?

Immutable data structures are data structures that cannot be changed after they have been created. This is important because it means that once you create an immutable data structure, you can be sure that it will always contain the same data. This can be useful when you need to share data between different parts of your code or between different people, because you can be sure that the data will not be changed.

15. Can you explain what tail recursion is and its importance?

Tail recursion is a type of recursion where the last statement in the function is a recursive call. This is important because it allows the compiler to optimize the function so that it doesn’t use up extra memory when it runs.

16. Why do you think concurrency is so important in modern applications?

Concurrency is important in modern applications because it allows for better performance and scalability. By being able to process multiple tasks simultaneously, your application can get more done in less time. This is especially important for applications that need to handle a lot of traffic or data.

17. What are the advantages of Phoenix over Rails?

There are several advantages that Phoenix has over Rails, including:

– Phoenix is faster than Rails, due to its use of the Erlang VM
– Phoenix has built-in support for websockets, making real-time applications easier to build
– Phoenix uses a functional programming style, which can lead to more concise and maintainable code
– Phoenix has better tooling for debugging and performance profiling

18. What are some popular frameworks built on top of Elixir?

Some popular frameworks built on top of Elixir are Phoenix, Ecto, and Plug.

19. What is the recommended way to build long running jobs with Elixir?

The recommended way to build long running jobs with Elixir is to use the GenServer module. GenServer is a process-based server that allows you to define a set of functions that can be called by other processes. This makes it ideal for building long running jobs, as you can easily manage the process and ensure that it stays up and running.

20. What is BEAM and what role does it play in Elixir?

BEAM is the virtual machine that Elixir runs on. It is responsible for running Elixir code and providing services to Elixir processes.