The Joys and Woes of Pair Programming

There are a few agile practices opens a new window that I really love. Pair programming opens a new window is one of them.

We try to do it as much as possible at OmbuLabs opens a new window . We usually keep the sessions under two hours and try to follow a regular schedule.

When we find ourselves blocked by a code problem, we use our daily scrum to coordinate a pairing session. It’s quite a step up from rubberducking opens a new window or using a cardboard programmer opens a new window to find a solution to a problem.

@mauro_oto and I pair programming

The Joys

As a Senior developer, I find that pairing sessions are great for coaching Junior developers. I enjoy teaching them about best practices, design patterns, frameworks, languages, code style, XP opens a new window , and TDD opens a new window .

From the point of view of a Junior developer, I believe it’s a great opportunity to learn from someone who “has been there before”. When you program with someone with more experience, you will often learn about design patterns, elegant object-oriented solutions, tips and tricks.

As a Senior developer, pair programming is a great way to mentor a Junior developer. It’s also a good way to get better at explaining some of the things you know and to learn in the process.

When I’m struggling, it’s great to have a sounding board for my ideas. It’s useful to have a brainstorming session about potential solutions to a problem. We all know that for every problem there is a:

  • 2 hours solution
  • 2 days solution
  • 2 weeks solution

[I used *2* but it could be *n*. You get the point]

Pairing with someone you put everything in perspective. You evaluate your resources, your limitations and you explore the different solutions until you find something that is both elegant and pragmatic for both of you.

When you pair, you tend to avoid ugly hacks because someone is right there watching what you are doing. As the driver, you can write your ugly hack just to show what you want to do, then have your navigator improve it.

The Woes

To be completely honest, sometimes I have a hard time getting myself to pair with someone else. I tend to think that I’ll go faster by myself. But this is not usually the case, especially when I’m facing hard problems.

As a Senior developer sometimes you could actually go faster by yourself, but you would miss out on the opportunity of coaching Junior developers.

If the sessions are too long, the navigator will lose interest or get lost if the Senior developer is driving. The navigator should definitely question weird-looking code, but that might slow down the driver.

Pairing sessions can be intense. After you are done, you need to take a break before you continue with something else.

The navigator must definitely point out code smells and ask the driver to improve them. If the driver can’t, the navigator should improve the smelly code. That will definitely slow you down, but it will produce better code.

The biggest woe is that you will produce code at a slower speed, but the code will usually end up with more quality, more coverage and better readability than if you were programming by yourself.

Conclusion

If you haven’t tried pair programming yet, you should definitely give it a try. After you do, you will likely incorporate it to your weekly routine.

The joys and advantages far outweigh the woes and disadvantages of this practice.

Tips

  • Pair when you have programmer’s block opens a new window .
  • Pair when you have been stuck trying to solve a problem for way too long and haven’t made any progress.
  • Keep pairing sessions under two hours.
  • Don’t do all the driving during the session, take turns.
  • Pair with someone with more experience than you.
  • Pair with someone with less experience than you.
  • Pair when you are unsure about the solution you just wrote.
  • Be communicative. Guide the navigator through your thought process. Talk about the alternatives and why you go one way or the other.
  • Keep a post-it block right next to you. Write down things that could be improved but not during the session.
  • Interrupt only when necessary.
  • If you are the navigator, don’t be afraid to grab the keyboard to show a better alternative to the code that the driver is writing.
  • Put your phone on do not disturb mode.

[The title of this article was inspired by one of my favorite chapters opens a new window in The Mythical Man-Month opens a new window by Fred Brooks]