Product Perfect

Elixir Enum is a module in the Elixir programming language, which provides a set of algorithms to enumerate over enumerable data types. It was introduced as part of Elixir, a dynamic and functional language built on top of the Erlang virtual machine (BEAM), created by José Valim in 2011. The Enum module offers high-level operations for collections, including sorting, grouping and filtering functions among others. Its capabilities are rooted in functional programming principles that enable more efficient manipulation and transformation of data sets. This powerful tool significantly enhances productivity by simplifying complex coding tasks within the software development process.

Ask the right questions secure the right Elixir Enum talent among an increasingly shrinking pool of talent.

First 20 minutes

General Elixir Enum app knowledge and experience

The first 20 minutes of the interview should seek to understand the candidate's general background in Elixir Enum application development, including their experience with various programming languages, databases, and their approach to designing scalable and maintainable systems.

How would you define Elixir Enum?

Elixir Enum is a module with built-in functions for working with enumerables - data types that support enumeration. It provides a set of algorithms that act on enumerables, returning a result or a new enumerable.

What is the purpose of the Enum.map function?

The Enum.map function is used to transform a given enumerable by applying a function to every element. It returns a new list with the results.

Describe the difference between Enum.reduce and Enum.map.

Enum.reduce is used to reduce the enumerable to a single value by applying a function to each element, while Enum.map is used to transform the elements of the enumerable and return a new list.

How would you use the Enum.filter function?

Enum.filter function is used to filter out elements in an enumerable. It takes an enumerable and a function. It applies the function to each element and if the function returns true, the element is included in the resulting list.

What are the uses of Enum.sort function?

Enum.sort function is used to sort the elements in an enumerable. It can be used with a function that defines the sort order or without a function in which case it sorts in ascending order.

The hiring guide has been successfully sent to your email address.

Oops! Something went wrong while submitting the form.

What you’re looking for early on

Does the candidate have a solid understanding of Elixir Enum?

Can the candidate demonstrate experience with functional programming?

Does the candidate show problem-solving skills?

How well does the candidate understand concurrent and distributed programming?

Next 20 minutes

Specific Elixir Enum development questions

The next 20 minutes of the interview should focus on the candidate's expertise with specific backend frameworks, their understanding of RESTful APIs, and their experience in handling data storage and retrieval efficiently.

How would you use Enum.into function in Elixir?

Enum.into function is used to insert elements from one enumerable into another. It takes two arguments, the enumerable to take elements from and the enumerable to insert elements into.

What is the difference between Enum.any? and Enum.all? functions?

Enum.any? checks if there is at least one element in the enumerable for which the provided function returns true. Enum.all? checks if all elements in the enumerable return true for the provided function.

How would you use Enum.chunk_every function?

Enum.chunk_every function is used to split the enumerable into chunks of a specified size. It returns a list of chunks.

What are the uses of Enum.count function?

Enum.count function is used to count the number of elements in an enumerable. It can also be used with a function to count the number of elements that satisfy a certain condition.

How would you use Enum.drop function?

Enum.drop function is used to remove a certain number of elements from the beginning of an enumerable. It takes the enumerable and the number of elements to drop as arguments.

The hiring guide has been successfully sent to your email address.

Oops! Something went wrong while submitting the form.

At this point, a skilled Elixir Enum engineer should demonstrate strong problem-solving abilities, proficiency in Elixir Enum programming language, and knowledge of software development methodologies. Red flags include lack of hands-on experience, inability to articulate complex concepts, or unfamiliarity with standard coding practices.

Digging deeper

Code questions

These will help you see the candidate's real-world development capabilities with Elixir Enum.

What does the following Elixir Enum code do?
Enum.map([1, 2, 3, 4], fn x -> x * 2 end)
This code doubles each element in the list. The map function applies the anonymous function to each element in the list, which multiplies the element by 2.
What will be the output of the following Elixir Enum code?
Enum.reduce([1, 2, 3, 4], 0, fn x, acc -> x + acc end)
The output will be 10. This code sums up all the elements in the list. The reduce function applies the anonymous function to each element in the list and an accumulator, which starts at 0.
What does the following Elixir Enum code do?
Enum.filter([1, 2, 3, 4], fn x -> rem(x, 2) == 0 end)
This code filters out all the odd numbers in the list. The filter function applies the anonymous function to each element in the list and keeps the elements for which the function returns true.
What does the following Elixir Enum code do?
Enum.each([1, 2, 3, 4], fn x -> IO.puts(x) end)
This code prints each element in the list to the console. The each function applies the anonymous function to each element in the list, which prints the element.

Wrap-up questions

Final candidate for Elixir Enum Developer role questions

The final few questions should evaluate the candidate's teamwork, communication, and problem-solving skills. Additionally, assess their knowledge of microservices architecture, serverless computing, and how they handle Elixir Enum application deployments. Inquire about their experience in handling system failures and their approach to debugging and troubleshooting.

What is the difference between Enum.drop_while and Enum.take_while?

Enum.drop_while drops elements from the beginning of an enumerable while the provided function returns true. Enum.take_while takes elements from the beginning of an enumerable while the function returns true.

How would you use Enum.flat_map function?

Enum.flat_map is used to transform each element in an enumerable to another enumerable, then flattens the results into a list.

What is the use of Enum.group_by function?

Enum.group_by function is used to group elements in an enumerable based on the result of a function. It returns a map where the keys are the results of the function and the values are lists of elements that returned the same key.

Elixir Enum application related

Product Perfect's Elixir Enum development capabilities

Beyond hiring for your Elixir Enum engineering team, you may be in the market for additional help. Product Perfect provides seasoned expertise in Elixir Enum projects, and can engage in multiple capacities.

Elixir Enum Consultive assessments

Elixir Enum Application Conversion Assessment Elixir Enum Application Integration Assessment Elixir Enum Data & Database Integration Assessment

Custom Elixir Enum development projects

Custom Elixir Enum App Conversion Elixir Enum Custom App Development Process App UI Design for Elixir Enum Facelifts

Hiring guide for Elixir Enum Engineers

Elixir Enum Developer Hiring Guide

What you’re looking for early on

The ideal back-end app developer

What you’re looking to see on the Elixir Enum engineer at this point.

Elixir Enum Consultive assessments

Custom Elixir Enum development projects