Code Interviews Online: “Pair-Programming” or Full Challenge?

A code interview online is intended to engage a software-development candidate in actual coding tasks that the candidate, if hired, would do on the job.

It was developed, and has been greatly refined, now, to provide a company with more objective, “real world” evidence of coding ability than the traditional “talk” interview by telephone or in person. In that situation, one or more interviewers from the company poses questions such as, “How would you rate your coding skill?” Or ask the candidate to describe the most recent coding assignment he or she faced.

The online coding interview goes beyond that type of interview by asking a candidate to complete online tasks that challenge—depending upon the test—coding skills, problem-solving skills, debugging skills, and other capabilities the company requires on its software development teams. In order to recreate the future job environment, the interview might ask the candidate writing online code to:

  • Complete a basic task like inverting a binary tree
  • Write a particular algorithm
  • Debug a piece of code
  • Respond to a client’s hypothetical coding question

In some cases, the interviewer watches the candidate perform the task and even asks questions about why a candidate is making a certain decision.

However, some of these tasks (such as writing an algorithm) will be done on the job with specific tools. The candidate will be using those tools to solve software-development, systems architecture, and debugging problems within a team that’s moving the company’s software agenda forward. For that reason, some online interviews, such as Woven’s technical assessment, have advanced from coding tasks to challenges that candidates in specific roles might be assigned.

Additionally, assessment of the results of the online coding interview can be mechanical (right/wrong), be performed by HR personnel, or involve senior engineers in determining how well the candidate would perform a given role. Woven’s Scenario Evaluation Engine is the only human structured scoring to evaluate the whole candidate.

Online coding interviews offer an opportunity to broaden the scope of the recruitment and hiring process. Candidates at any distance can be assessed using the interview, and those who cannot attend an in-person interview on a given day aren’t eliminated.

Online code editors and online coding tools enable the candidates to write code (say, HTML online) on the screen for the test. Free online code editors for interviews enable companies and their HR departments to create their own coding interviews—if they choose to go that route instead of retaining a professional coding challenge firm.

Write code online

You’re probably wondering what the best coding language is to use in online interviews. Tests exist for all the mostly commonly used languages, including C++, Python, and Java. Interviewers are often both good engineers and programming language polyglots, able to read code in whatever language the candidate uses. If the candidate uses the language with which he or she is most comfortable, the test can focus less on language familiarity and more on skill in using coding to solve problems.

What is C++?

A general-purpose programming language, C++ has been used since it was designed by Bjarne Stroustrup in the 1990s. It is a version of an earlier code, C, that includes object-oriented elements (a cluster of four major programming language principles). It certainly is one of the foremost programming languages and is most widely used, today, by programmers and developers of applications. C++ is the premier programming language for game development and has been used to create some of the most famous games and game engines. The user-friendly C++ online compiler enables you to write C++ code and run it online. The C++ online code editor also supports taking input from the user and applying it.

What is Python?

Python is another high-level, general-purpose programming language. It is known for emphasizing code readability with its use of significant indentation, for example. Both Python’s language constructs and its object-oriented approach are intended to help programmers write clear, logical code for projects on any scale. Python is also intended to be a small core language with a large standard library to support the writing of code. Older than C++ and dating back to the 1980s, Python remains one of the most popular programming languages. Python online compilers will write and run code for many applications.

What is Java?

Java is both a programming language and a computing platform that was released in 1995 by Sun Microsystems. Today, Java is everywhere — in data centers, game consoles, cellphones, laptops, and supercomputers. One reason is that Java is platform independent, running on any computer with an installed Java Runtime Environment. Many Java online compilers, with slightly different names, enable you to write your code in an editor and hit “run” to execute it.

The best online code editor for interviews

A chief tool of software developers today is the online code editor or online text editor. A host of online text editors is available to help you code from any computer that has internet access. Using this Integrated Development Environment (IDE) and its web applications, coding can be easily shared for collaboration so that a colleague can step in to help with your work.


Among the most favored and best online code editors is CodePen, viewed as fast, easy to use, and enabling a web developer to write and share HTML/CCC/JS code online. This online editor is free; without an account, you can start writing code and working on new web applications on your web browser.

Jdoodle online compiler C++ 

You certainly can take your pick of highly recommended C++ compilers. but Jdoodle is described as fun to use and has “astonishing execution speed.” And, it supports compiler and interpreter functions for other programming languages. Among its features are code coloring and auto-suggestion.

OneCompiler JS online

This free online compiler enables you to write, run, and share widely used JavaScript code online. It is by no means the only online compiler for JavaScript language, but it is rich in features, easy, and fast. OneCompiler JS also has reference programs you can use as samples to create your own.

Code share online

A feature of most of these online editors or compilers is the capability of sharing code online, so it can be reviewed, edited, or continued by others. There are many ways to share online, and some compilers (as we will discuss later) make this their chief emphasis.


One widely used online editor, Codeshare, enables you to write or copy code and share it with friends and colleagues for “pair-programming” and troubleshooting, for example. Codeshare is widely used for setting coding tasks and observing real-time performance of a candidate remotely or in person. Universities around the world use Codeshare to teach students coding in real-time and in a collaborative setting.

Code collaboration

Code collaboration tools are also known as remote pair-programming software. Dozens of code collaboration tools—proprietary or free—enable developers to work together on coding from any location. This is made possible with features such as remote control, screen sharing, chat/messaging, and video conferencing. The web-based applications enable users to work together in real-time over the internet. Code collaboration can be used across different platforms and different devices, and a development team, for example, can cooperate in keeping code up to date. Two examples: AWS Cloud9 and CodeSandbox.


AWS Cloud9 is an online collaboration tool (technically an IDE) to write, run, and debug code using only your browser. Essential tools for the most popular programming languages (JavaScript, Python) come with the AWS package and do not have to be installed or configured on your device before you start your project. Also, being cloud-based allows work from the home, office, or anywhere that there is an internet-connected machine. Again, pair programming is a major emphasis so that AWS can support certain kinds of online coding interviews.


Known as a super-fast development environment, CodeSandbox supports rapid web development on your browser. It requires no setup, has a template to boost new projects, and enables you to begin coding almost instantly. Like other collaboration software, CodeSandbox is for sharing to get feedback from other coders and create code together either in real time or asynchronously. Changes can be seen instantly, so friends, a team, or colleagues can join you with just a URL.

Common CoderPad interview questions

For companies that want to go it alone when interviewing and testing, one of the first and most popular coding interview platforms is CoderPad. It is a simple and affordable tool to interview candidates online. Experienced company engineers, if they have the time and inclination, can look up CoderPad interview tips, set up their own interviews from scratch, and track candidates/start new interviews. The platform works with most common programming languages and executes quickly, so that candidates can debug code as they are creating it. On the other hand, CoderPad does not test frontend skills, backend technologies and frameworks, or collaboration on complex projects.

CoderPad offers an online “Question Bank” from which company interviewers can create and share questions for live or take-home interviews. A company can standardize these interview questions so that candidates interviewing for the same role get essentially the same test.

Since CoderPad is widely used to create interviews, especially pair-programming interviews, it has questions in most common programming languages.  Here are some of the most common coding questions focused on Java and Python that are likely to appear on the CoderPad interview test:

CoderPad interview questions Java

  • Write a Java program to replace certain characters from String like public String replace (String str, char ch)
  • Write a Java program to print Fibonacci series up to 100. This is among the most popular coding interview questions is Java programming.
  • FizzBuzz problem: Write a Java program that prints the numbers from 1 to 50. But, for multiples of three, print “Fizz” instead of the number and for the multiples of five print “Buzz”. For numbers which are multiples of both three and five print “FizzBuzz”.
  • Write a Comparator in Java to compare two employees based upon their name, departments, and age.
  • Design a vending machine in Java which vends items based upon four denominations of coins and return coin if there is no item. This kind of Java coding interview question appears in a written test.
  • Write a Java program to check if a number is Armstrong or not.
    This is a common Java-based question to get at skills in programming logic. The question probably tells the interviewee the definition of an Armstrong number.

Coderpad interview questions Python 

  • How do you debug a Python program?
  • What is <Yield> Keyword in Python?
  • How to convert a list into a string
  • How to convert a list into a tuple
  • How to convert a list into a set
  • How to count the occurrences of a particular element in the list

Woven is the CoderPad and codeshare alternative

CoderPad and many other online coding tests, as we have seen, focus on pair-programming—using online editing programs to bring together the interviewers and job candidates online in a shared environment. In these interviews, your company’s HR personnel or software engineers may pose the questions in real-time. They may ask the candidate why he or she is making a certain decision on the test. As compared with the traditional hiring interview, which poses more general questions about the candidate’s degree and certification credentials, the combined code interview and test may represent progress.

Woven: an asynchronous test

Woven has taken a different direction in the development, administration, and evaluation of online coding challenges. We believe that the pair-programming interview/online test is a hybrid that fails to offer the full value of an online coding challenge.

In pair-programming interview tests, the candidate’s focus is split between the interviewers and the test. We do not think this provides the most objective evidence of the candidate’s use of coding skills in problem-solving needed for creative development, system architecture, and debugging. In the work environment, the candidate, if hired, will be given a problem and a deadline and will focus all concentration on that assignment.

An added benefit is that your HR personnel can cast a wider net in search of talent. The online coding challenge can be taken anywhere, including in the candidate’s home or present office. Those who are required to be home during certain hours (for example, when their children are home from school) are not excluded from the interview.

Woven test development engineer roles

Another issue is that the commonly posed questions about standard programming language functions and how to perform them do not necessarily test creative skills in defining and posing solutions to real problems. At Woven, we do not draw questions from a question bank. Our online coding challenge is aimed at a specific role in a company such as Mid/Senior Fullstack Engineer, Engineering Manager, Junior/Mid Frontend Engineer, and Mid/Senior Generalist Engineer, to name a few.

Our focus is not specific questions about vocabulary, component skills, or languages. Instead, we focus on creating real challenges that require working in code to solve problems in debugging, technical communication, systems thinking, backend programming, and frontend programming.

These capabilities are tested in challenges as similar as possible to the software challenges that your company must face in order to grow.

Woven test evaluations by senior engineers

With Woven, test results are evaluated by at least two senior engineers, who score the test blind, then consult and report their assessment to your company with a specific recommendation.

This focus on objective evidence also helps open opportunities and increase diversity on your company’s engineering staff. You can, of course, ask questions in personal interviews about teamwork, work environment preferences, and reaction to experiences, but our assessment sets a firm foundation of objective, comparable, work-related performance.

Try Woven today

Your first step in learning more about Woven’s online coding challenges is to start your free trial. We invite you to try our product for yourself; it’s the only technical assessment platform that goes beyond code to test real-world problem-solving and build high-performing engineering teams.