What is Pair Programming? Advantages, Challenges, Tutorials & More

Developers do their best work when they’re inspired and empowered, as we discussed recently in this post. That means equipping your developers with the tools and resources they need to be more efficient, blending agility with accuracy to build better products, faster. There are several tactics for achieving these goals, many of which work well in tandem. Application performance monitoring, for instance, helps you take a proactive approach to monitoring rather than responding to issues only after they’ve reached your users. Another method for boosting efficiency is pair programming, Let’s take a look at pair programming advantages, concept, and challenges of pair programming.

Definition of Pair Programming

As the name implies, pair programming is where two developers work using only one machine. Each one has a keyboard and a mouse. One programmer acts as the driver who codes while the other will serve as the observer who will check the code being written, proofread and spell check it, while also figuring out where to go next. These roles can be switched at any time: the driver will then become the observer and vice versa.

It’s also commonly called “pairing,” “programming in pairs,” and “paired programming.”

Pair Programming Advantages

There are several compelling reasons you should consider this strategy:

• Two heads are better than one. If the driver encounters a hitch with the code, there will be two of them who’ll solve the problem.
• More efficient. Common thinking is that it slows down the project completion time because you are effectively putting two programmers to develop a single program, instead of having them work independently on two different programs. But studies have shown that two programmers working on the same program are only 15% slower than when these programmers work independently, rather than the presupposed 50% slow down.
• Fewer coding mistakes. Because there is another programmer looking over your work, it results in better code. In fact, an earlier study shows that it results in 15% fewer bugs than code written by solo programmers. Plus, it allows the driver to remain focus on the code being written while the other attends to external matters or interruption.
• An effective way to share knowledge. Code Fellows talks about how it could help programmers learn from their peers in this blog post. It would allow programmers to get instant face-to-face instruction, which is much better than online tutorials and faster than looking for resources on the Internet. Plus, you can learn things better from your partner, especially in areas that may be unfamiliar to you. Developers can also pick up best practices and better techniques from more advanced programmers. It can also facilitate mentoring relationships between two programmers.
• Develops your staff’s interpersonal skills. Collaborating on a single project helps your team to appreciate the value of communication and teamwork.

In sum, it helps your programmers learn from each other while coming up with programs and applications with better code quality and fewer bugs.

Alistair Cockburn of Humans and Technology and Laurie Williams of the University of Utah – Computer Science Department have come up with a bullet list of benefits:

• Fewer mistakes are introduced into your code because a lot of errors are caught as they are being typed. This level of continuous code reviews gives rise to fewer bugs in your code.
• You have shorter and tighter code.
• Two people can solve the problems that crop up along the way faster and quicker.
• Your developers learn more about things that are specific to the applications that they are working on as well as software development in general, best practices, and other areas.
• You have more people who know how the new program works. This means that if one of the pair leaves the company, it will not kill the project.
• Your team develops better interpersonal and social skills. Team members can learn to communicate with each other, work together, and share information.
• Your team members are more satisfied.

Why is Programming in Pairs Better than Code Reviews?

Code reviews are a process wherein another programmer takes a look at your code to find something that needs improvement or find defects in it. It combines testing with quality control to ensure that everything in your code is good. This helps you ensure that your code is improved.

However, it is challenging to find somebody to review your code because people may not want to look at another’s code and understand their reasoning just for the sake of checking its quality. Most of the time, code reviews happen when somebody else tries to add some functionality to your code, or fixes bugs. But by then, you, as the original programmer, might not even be around to appreciate the code review.

With pairing, it is like having somebody review your code instantly and regularly. It is a higher form of code reviews. Two people have to be there and understand the program being written. And if one sees problems with the other’s code, then it can be instantly corrected. You also have fewer chances of having bugs written into your code. Code reviews are not as proactive as you have to wait until the code is completed — bugs and all — before somebody could take a look at and correct it.

Challenges of Pairing

The common problems observed when it comes to pair programming include the following:

• The pair should be equally engaged and be participative for the duration of the task. Otherwise, there would be no benefits.
• People who have not tried it may think that it will double the cost because you are putting two programmers on one project. However, this is a misconception that needs to be clarified. On top of the fact that pairing, done right, will only result in 15% slowdowns in terms of the individual output, it actually speeds up the coding process and ensures better quality code, which lessens the chances that the program would have to be redone.
• Pair programming should also be a programming out loud process, where the pair is verbally detailing what it is doing.
• It’s not something that you can force your team to do. It’s highly social and interactive, so you should be able to detect pairs that may have problems with each other, such as clashing personalities or even problems with personal hygiene.

How to Effectively Pair Your Programmers

The best way to approach pairing is to partner two programmers and have them share a computer. Make them work together to architect, code and then test their codes in a genuine sense of a partnership. While the ideal setup would include two programmers who are equally skilled (expert – expert or novice – novice), you can also use pair programming for training and educational purposes (expert – novice).

The pair should be able to decide how to split the work, and it is advisable that they should switch roles often.

Additional Resources and Tutorials

For further reading on pair programming, including helpful tutorials, visit the following resources:

• Extreme Programming – Pair Programming
• Pair Programming Tutorial Video
• Pair Programming Tutorial
• Try pair programming
• Rethinking Pair Programming

Author

Alexandra

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