Why you should use Scala Online Test?

The Scala Online Test makes use of scenario-based questions to test for on-the-job skills as opposed to theoretical knowledge, ensuring that candidates who do well on this screening test have the relavant skills. The questions are designed to covered following on-the-job aspects: Ability to write clean and efficient Scala code Proficiency in functional programming concepts like immutability, higher-order functions, and pattern matching Strong understanding of object-oriented programming principles and their application in Scala Expertise in working with Scala collections and their associated methods Experience in error handling and writing robust code Knowledge of concurrency and parallelism in Scala Familiarity with type inference and type checking in Scala Understanding of traits and mixins in Scala Ability to work with and test Scala code using appropriate frameworks Understanding of immutable data structures and their advantages in Scala

Scala Online Test

Q: What topics are covered in the Scala Online Test?

Scala programming language Functional programming Object-oriented programming Collections Pattern matching Concurrency and parallelism Error handling Type inference Traits and mixins Higher-order functions Immutable data structures Scala test frameworks

About the test:

The Scala Online test uses scenario-based MCQs to evaluate candidates on their knowledge and proficiency in working with Scala programming language, including core concepts, syntax, and functional programming principles. The test assesses a candidate's ability to design and develop efficient and scalable applications using Scala. The test includes a coding question to evaluate hands-on Scala programming skills.

Covered skills:

Scala programming language
Object-oriented programming
Pattern matching
Error handling
Traits and mixins
Immutable data structures

Functional programming
Collections
Concurrency and parallelism
Type inference
Higher-order functions
Scala test frameworks

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9 reasons why

Adaface Scala Test is the most accurate way to shortlist Scala Developers

Reason #1

Tests for on-the-job skills

The Scala Online Test helps recruiters and hiring managers identify qualified candidates from a pool of resumes, and helps in taking objective hiring decisions. It reduces the administrative overhead of interviewing too many candidates and saves time by filtering out unqualified candidates at the first step of the hiring process.

The test screens for the following skills that hiring managers look for in candidates:

Proficient in Scala programming language
Strong understanding of functional programming
Expertise in object-oriented programming
Knowledge of collections in Scala
Ability to effectively use pattern matching
Experience in concurrency and parallelism in Scala
Skilled in error handling
Familiarity with type inference in Scala
Able to utilize traits and mixins in Scala
Proficient in higher-order functions
Understanding of immutable data structures in Scala
Familiarity with Scala test frameworks

Reason #2

No trick questions

Traditional assessment tools use trick questions and puzzles for the screening, which creates a lot of frustration among candidates about having to go through irrelevant screening assessments.

View sample questions

The main reason we started Adaface is that traditional pre-employment assessment platforms are not a fair way for companies to evaluate candidates. At Adaface, our mission is to help companies find great candidates by assessing on-the-job skills required for a role.

Why we started Adaface

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Reason #3

Non-googleable questions

We have a very high focus on the quality of questions that test for on-the-job skills. Every question is non-googleable and we have a very high bar for the level of subject matter experts we onboard to create these questions. We have crawlers to check if any of the questions are leaked online. If/ when a question gets leaked, we get an alert. We change the question for you & let you know.

How we design questions

These are just a small sample from our library of 10,000+ questions. The actual questions on this Scala Online Test will be non-googleable.

🧐 Question
Medium placeholder method	Try practice test
Review the following Scala code. “placeholder” is a placeholder function to be replaced with an actual Scala in-built method. What should ‘placeholder’ be so that the a, b, c in the code evaluate to true?
Medium Compilation Errors	Try practice test
Which lines in the following Scala code will lead to compilation errors?
Easy take and reduceLeft List String	Try practice test
What will the following Scala code print?
Easy Registration Queue Logic Queues	Solve
We want to register students for the next semester. All students have a receipt which shows the amount pending for the previous semester. A positive amount (or zero) represents that the student has paid extra fees, and a negative amount represents that they have pending fees to be paid. The students are in a queue for the registration. We want to arrange the students in a way such that the students who have a positive amount on the receipt get registered first as compared to the students who have a negative amount. We are given a queue in the form of an array containing the pending amount. For example, if the initial queue is [20, 70, -40, 30, -10], then the final queue will be [20, 70, 30, -40, -10]. Note that the sequence of students should not be changed while arranging them unless required to meet the condition. ⚠️⚠️⚠️ Note: - The first line of the input is the length of the array. The second line contains all the elements of the array. - The input is already parsed into an array of "strings" and passed to a function. You will need to convert string to integer/number type inside the function. - You need to "print" the final result (not return it) to pass the test cases. For the example discussed above, the input will be: 5 20 70 -40 30 -10 Your code needs to print the following to the standard output: 20 70 30 -40 -10
Medium Visitors Count Strings Logic	Solve
A manager hires a staff member to keep a record of the number of men, women, and children visiting the museum daily. The staff will note W if any women visit, M for men, and C for children. You need to write code that takes the string that represents the visits and prints the count of men, woman and children. The sequencing should be in decreasing order. Example: Input: WWMMWWCCC Expected Output: 4W3C2M Explanation: ‘W’ has the highest count, then ‘C’, then ‘M’. ⚠️⚠️⚠️ Note: - The input is already parsed and passed to a function. - You need to "print" the final result (not return it) to pass the test cases. - If the input is- “MMW”, then the expected output is "2M1W" since there is no ‘C’. - If any of them have the same count, the output should follow this order - M, W, C.

	🧐 Question	🔧 Skill
	Medium placeholder method	2 mins Scala	Try practice test
Review the following Scala code. “placeholder” is a placeholder function to be replaced with an actual Scala in-built method. What should ‘placeholder’ be so that the a, b, c in the code evaluate to true?
	Medium Compilation Errors	2 mins Scala	Try practice test
Which lines in the following Scala code will lead to compilation errors?
	Easy take and reduceLeft List String	2 mins Scala	Try practice test
What will the following Scala code print?
	Easy Registration Queue Logic Queues	30 mins Coding	Solve
We want to register students for the next semester. All students have a receipt which shows the amount pending for the previous semester. A positive amount (or zero) represents that the student has paid extra fees, and a negative amount represents that they have pending fees to be paid. The students are in a queue for the registration. We want to arrange the students in a way such that the students who have a positive amount on the receipt get registered first as compared to the students who have a negative amount. We are given a queue in the form of an array containing the pending amount. For example, if the initial queue is [20, 70, -40, 30, -10], then the final queue will be [20, 70, 30, -40, -10]. Note that the sequence of students should not be changed while arranging them unless required to meet the condition. ⚠️⚠️⚠️ Note: - The first line of the input is the length of the array. The second line contains all the elements of the array. - The input is already parsed into an array of "strings" and passed to a function. You will need to convert string to integer/number type inside the function. - You need to "print" the final result (not return it) to pass the test cases. For the example discussed above, the input will be: 5 20 70 -40 30 -10 Your code needs to print the following to the standard output: 20 70 30 -40 -10
	Medium Visitors Count Strings Logic	30 mins Coding	Solve
A manager hires a staff member to keep a record of the number of men, women, and children visiting the museum daily. The staff will note W if any women visit, M for men, and C for children. You need to write code that takes the string that represents the visits and prints the count of men, woman and children. The sequencing should be in decreasing order. Example: Input: WWMMWWCCC Expected Output: 4W3C2M Explanation: ‘W’ has the highest count, then ‘C’, then ‘M’. ⚠️⚠️⚠️ Note: - The input is already parsed and passed to a function. - You need to "print" the final result (not return it) to pass the test cases. - If the input is- “MMW”, then the expected output is "2M1W" since there is no ‘C’. - If any of them have the same count, the output should follow this order - M, W, C.

	🧐 Question	🔧 Skill	💪 Difficulty	⌛ Time
	placeholder method	Scala	Medium	2 mins	Try practice test
Review the following Scala code. “placeholder” is a placeholder function to be replaced with an actual Scala in-built method. What should ‘placeholder’ be so that the a, b, c in the code evaluate to true?
	Compilation Errors	Scala	Medium	2 mins	Try practice test
Which lines in the following Scala code will lead to compilation errors?
	take and reduceLeft List String	Scala	Easy	2 mins	Try practice test
What will the following Scala code print?
	Registration Queue Logic Queues	Coding	Easy	30 mins	Solve
We want to register students for the next semester. All students have a receipt which shows the amount pending for the previous semester. A positive amount (or zero) represents that the student has paid extra fees, and a negative amount represents that they have pending fees to be paid. The students are in a queue for the registration. We want to arrange the students in a way such that the students who have a positive amount on the receipt get registered first as compared to the students who have a negative amount. We are given a queue in the form of an array containing the pending amount. For example, if the initial queue is [20, 70, -40, 30, -10], then the final queue will be [20, 70, 30, -40, -10]. Note that the sequence of students should not be changed while arranging them unless required to meet the condition. ⚠️⚠️⚠️ Note: - The first line of the input is the length of the array. The second line contains all the elements of the array. - The input is already parsed into an array of "strings" and passed to a function. You will need to convert string to integer/number type inside the function. - You need to "print" the final result (not return it) to pass the test cases. For the example discussed above, the input will be: 5 20 70 -40 30 -10 Your code needs to print the following to the standard output: 20 70 30 -40 -10
	Visitors Count Strings Logic	Coding	Medium	30 mins	Solve
A manager hires a staff member to keep a record of the number of men, women, and children visiting the museum daily. The staff will note W if any women visit, M for men, and C for children. You need to write code that takes the string that represents the visits and prints the count of men, woman and children. The sequencing should be in decreasing order. Example: Input: WWMMWWCCC Expected Output: 4W3C2M Explanation: ‘W’ has the highest count, then ‘C’, then ‘M’. ⚠️⚠️⚠️ Note: - The input is already parsed and passed to a function. - You need to "print" the final result (not return it) to pass the test cases. - If the input is- “MMW”, then the expected output is "2M1W" since there is no ‘C’. - If any of them have the same count, the output should follow this order - M, W, C.

Reason #4

1200+ customers in 75 countries

With Adaface, we were able to optimise our initial screening process by upwards of 75%, freeing up precious time for both hiring managers and our talent acquisition team alike!

Brandon Lee, Head of People, Love, Bonito

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Reason #5

Designed for elimination, not selection

The most important thing while implementing the pre-employment Scala Online Test in your hiring process is that it is an elimination tool, not a selection tool. In other words: you want to use the test to eliminate the candidates who do poorly on the test, not to select the candidates who come out at the top. While they are super valuable, pre-employment tests do not paint the entire picture of a candidate’s abilities, knowledge, and motivations. Multiple easy questions are more predictive of a candidate's ability than fewer hard questions. Harder questions are often "trick" based questions, which do not provide any meaningful signal about the candidate's skillset.

Science behind Adaface tests

Reason #6

1 click candidate invites

Email invites: You can send candidates an email invite to the Scala Online Test from your dashboard by entering their email address.

Public link: You can create a public link for each test that you can share with candidates.

API or integrations: You can invite candidates directly from your ATS by using our pre-built integrations with popular ATS systems or building a custom integration with your in-house ATS.

Reason #7

Detailed scorecards & benchmarks

View sample scorecard

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Reason #8

High completion rate

Adaface tests are conversational, low-stress, and take just 25-40 mins to complete.

This is why Adaface has the highest test-completion rate (86%), which is more than 2x better than traditional assessments.

Reason #9

Advanced Proctoring

Learn more

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About the Scala Assessment Test

Why you should use Pre-employment Scala Online Test?

The Scala Online Test makes use of scenario-based questions to test for on-the-job skills as opposed to theoretical knowledge, ensuring that candidates who do well on this screening test have the relavant skills. The questions are designed to covered following on-the-job aspects:

Ability to write clean and efficient Scala code
Proficiency in functional programming concepts like immutability, higher-order functions, and pattern matching
Strong understanding of object-oriented programming principles and their application in Scala
Expertise in working with Scala collections and their associated methods
Experience in error handling and writing robust code
Knowledge of concurrency and parallelism in Scala
Familiarity with type inference and type checking in Scala
Understanding of traits and mixins in Scala
Ability to work with and test Scala code using appropriate frameworks
Understanding of immutable data structures and their advantages in Scala

Once the test is sent to a candidate, the candidate receives a link in email to take the test. For each candidate, you will receive a detailed report with skills breakdown and benchmarks to shortlist the top candidates from your pool.

What topics are covered in the Scala Online Test?

Scala programming language
Scala is a modern, multi-paradigm programming language that combines the best features of object-oriented and functional programming. It provides a concise syntax, powerful pattern matching capabilities, and seamless integration with Java. Measuring this skill ensures that candidates have a strong understanding of Scala's fundamentals and can effectively utilize its features in real-world projects.
Functional programming
Functional programming is a programming paradigm that focuses on immutability, pure functions, and higher-order functions. It allows developers to write concise, modular, and maintainable code by avoiding shared state and side effects. Assessing a candidate's proficiency in functional programming is crucial to ensure they can leverage Scala's functional capabilities to write efficient and robust code.
Object-oriented programming
Object-oriented programming is a programming paradigm centered around objects that contain data and behavior. It promotes encapsulation, inheritance, and polymorphism to enable modular and reusable code. Evaluating a candidate's understanding of object-oriented principles in Scala is essential as it enables them to design and implement scalable and extensible solutions.
Collections
Collections are fundamental data structures in Scala that provide a wide range of operations for manipulating and processing sequences of elements. Proficiency in working with collections is vital to write efficient and expressive code. Evaluating a candidate's knowledge of Scala collections ensures they can leverage these powerful constructs effectively in their programs.
Pattern matching
Pattern matching is a powerful feature in Scala that allows developers to match complex data structures and extract values based on predefined patterns. It simplifies code and enables elegant solutions to various problems. Assessing a candidate's ability to use pattern matching effectively ensures they can write concise and readable code.
Concurrency and parallelism
Concurrency and parallelism are important concepts in modern software development to leverage the power of multi-core processors and increase the performance of applications. Evaluating a candidate's understanding of concurrency and parallelism in Scala ensures they can design and implement concurrent and efficient solutions that make efficient use of system resources.
Error handling
Error handling is a critical aspect of writing robust and maintainable software. Scala provides various mechanisms to handle exceptions and errors, such as try/catch blocks and the Option and Either types. Evaluating a candidate's knowledge of error handling in Scala ensures they can effectively handle and communicate errors in their code.
Type inference
Type inference is a feature in Scala that allows the compiler to automatically deduce the types of expressions and variables. It reduces the verbosity of code and promotes more concise and readable programs. Measuring a candidate's understanding of type inference ensures they can take advantage of this feature to write clean and expressive code.
Traits and mixins
Traits and mixins are powerful mechanisms in Scala that allow code reuse and composition. Traits enable the creation of reusable units of behavior, while mixins provide a way to combine multiple traits into a single class. Assessing a candidate's knowledge of traits and mixins ensures they can design and implement modular and reusable components in Scala.
Higher-order functions
Higher-order functions are functions that take one or more functions as arguments or return functions as results. They promote code modularity and enable the creation of more expressive and reusable code. Evaluating a candidate's proficiency in higher-order functions ensures they can effectively leverage this powerful functional programming concept in their Scala programs.
Immutable data structures
Immutable data structures are data structures whose state cannot be modified after creation. They simplify code by eliminating complex mutation and shared state issues. Assessing a candidate's understanding of immutable data structures in Scala ensures they can write code that is easier to reason about, test, and maintain.
Scala test frameworks
Scala test frameworks are libraries that provide a set of tools and utilities to write and execute tests for Scala applications. They enable developers to create comprehensive test suites and automate the validation of their code. Evaluating a candidate's familiarity with Scala test frameworks ensures they can write reliable and robust tests to ensure the correctness of their Scala code.
Full list of covered topics
The actual topics of the questions in the final test will depend on your job description and requirements. However, here's a list of topics you can expect the questions for Scala Online Test to be based on.
Basic syntax
Functions
Data types
Variables
Classes
Objects
Inheritance
Polymorphism
Encapsulation
Higher-order functions
Pattern matching
Collections
Immutable data structures
Error handling
Concurrency
Parallelism
Generics
Type inference
Traits
Mixins
Higher-order types
Partial functions
For-comprehensions
Implicits
Value classes
Case classes
Lazy evaluation
Basic IO operations
Handling XML and JSON
Concurrency tools (Futures, Promises, etc.)
Testing with Scala test frameworks
Distributed programming with Akka
Functional libraries (e.g. Cats, Scalaz)
Type classes
Parallel collections
Functional error handling
Stream processing
Parallel programming with Scala
Big Data processing with Scala
Reactive programming in Scala
Database access with Scala
Scala and Java interop
Concurrency patterns
Type-level programming
Closures
Immutable collections
Understanding the Scala compiler
Reading and writing files
Regular expressions
Type-safe configuration management
Working with futures
Asynchronous programming
Software design principles
Functional testing
Debugging techniques

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What roles can I use the Scala Online Test for?

Scala Developer
Big Data Developer
Senior Scala Software Engineer
Senior Big Data Engineer - Scala

How is the Scala Online Test customized for senior candidates?

For intermediate/ experienced candidates, we customize the assessment questions to include advanced topics and increase the difficulty level of the questions. This might include adding questions on topics like

Ability to apply Scala libraries and frameworks effectively
Proficiency in using Scala's built-in test frameworks for unit testing
Experience in optimizing Scala code for performance
Knowledge of advanced Scala language features
Strong problem-solving skills using Scala
Ability to debug and troubleshoot Scala code efficiently
Capability to write concise and readable Scala code
Understanding of Scala's interoperability with Java
Experience in writing concurrent and parallel Scala code
Proficiency in using functional programming libraries and frameworks in Scala

The coding question for experienced candidates will be of a higher difficulty level to evaluate more hands-on experience.

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The hiring managers felt that through the technical questions that they asked during the panel interviews, they were able to tell which candidates had better scores, and differentiated with those who did not score as well. They are highly satisfied with the quality of candidates shortlisted with the Adaface screening.

85%

reduction in screening time

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Scala Hiring Test FAQs

Can I combine multiple skills into one custom assessment?

Yes, absolutely. Custom assessments are set up based on your job description, and will include questions on all must-have skills you specify. Here's a quick guide on how you can request a custom test.

Do you have any anti-cheating or proctoring features in place?

We have the following anti-cheating features in place:

Non-googleable questions
IP proctoring
Screen proctoring
Web proctoring
Webcam proctoring
Plagiarism detection
Secure browser
Copy paste protection

Read more about the proctoring features.

How do I interpret test scores?

The primary thing to keep in mind is that an assessment is an elimination tool, not a selection tool. A skills assessment is optimized to help you eliminate candidates who are not technically qualified for the role, it is not optimized to help you find the best candidate for the role. So the ideal way to use an assessment is to decide a threshold score (typically 55%, we help you benchmark) and invite all candidates who score above the threshold for the next rounds of interview.

What experience level can I use this test for?

Each Adaface assessment is customized to your job description/ ideal candidate persona (our subject matter experts will pick the right questions for your assessment from our library of 10000+ questions). This assessment can be customized for any experience level.

Does every candidate get the same questions?

Yes, it makes it much easier for you to compare candidates. Options for MCQ questions and the order of questions are randomized. We have anti-cheating/ proctoring features in place. In our enterprise plan, we also have the option to create multiple versions of the same assessment with questions of similar difficulty levels.