Posts By: Gregg Caines

Patterns of the Swarm

On our teams, we do our best to ensure that we're fully focused on the most important thing that our team could be doing. To do that, we often "swarm" on the top priority: this is some internal documentation on what that looks like in practice!

Swarming is when a team is as fully dedicated to their absolute top priority as possible. This is the ideal state for maximum productivity. This is a list of patterns for swarming. No one pattern works in every scenario. Some patterns can be combined! It might be the right move for a group to change patterns in the middle work! We're probably also missing great patterns! Get creative! These are just suggestions and starting points.

💡 Also please note that full-team swarming is often impossible or suboptimal in many cases. You can't just keep adding more people to the same task and always expect that addition to be effective (e.g., nine women can't make a baby in one month).

Group Programming

Group programming is any kind of programming with more than 1 person on one screen at a time. There are many different kinds and you should decide which one makes sense instead of just adopting one for every situation. You will want to consider the goal of this type of collaboration, the skill levels and background knowledge of everyone involved, the responsibilities of everyone in the group, and the type of work you're trying to accomplish.


  • "navigator" — the person talking about what needs to be done on a high level
  • "driver" — the person with their hands on the keyboard making that happen
  • "observer" — anyone else that is just observing

Every group programming pattern here has a single navigator and single driver for the sake of simplicity.

Observers will have an extremely hard time staying engaged unless they are very regularly rotated into more engaging roles.


  • Group programming is most useful when you're introducing new people to a code-base, or working on an integration between two platforms.
  • Group programming is extremely exhausting and should involve heavy, heavy use of breaks. I'd recommend 15 minutes per hour AT MINIMUM and adjusting as you feel necessary.
  • Not everyone in the group needs to be a software developer for this to be useful.
  • Group programming with just two people is generally called Pair programming or pairing.
  • Group programming with more people is generally called mob programming or mobbing

Pair Programming

Peer Pairing

A type of pair programming where both developers have roughly the same level of expertise and background knowledge.

  • Recommended for: Really hard things or really unfun work that is less unfun with a friend.
  • Not Recommended for: Simple straightforward tasks: try Divide and Conquer instead. Cases where the work would benefit from more eyes, or when we want to spread knowledge/skills with more people in similar ways: try mob programming.

Mentor Pairing

A type of pair programming where one developer is trying to teach another developer something as they do the work together. The two developers could have things to learn from each other, and one of them could possibly not even be a developer at all.

You'll want to be very thoughtful about who should be the navigator and who should be the driver depending on your teaching goals. You may or may not want to rotate roles.

  • Recommended for: Cases where we want one person to teach another person something in a hands-on way. Hands-on teaching on real work is generally pretty engaging and practical compared to more academic approaches.
  • Not Recommended For: Times when multiple people need the same mentoring — try Directed Mobbing.

Ping-Pong Pairing

A type of pair programming where the developers practice TDD with one person writing a test and the other writing the app code that passes it. You could have only one person writing the tests during the session, or the duties could rotate. Recommended for: really complex and detailed uses cases where an adversarial testing technique can drive out a better result.

Not recommended for: straightforward building (like CRUD stuff)

Mob Programming

Mob-programming is group programming with more than 2 people. The additional people beyond the driver and the navigator are almost always observers to keep things simple. The traditional recommendation is to change the driver every 10 minutes. Some examples are: Directed Mobbing , Peer Mobbing

Directed Mobbing

Directed mobbing is a form of mob programming when there's a group trying to learn something from a particular expert . In general that expert should never be driving so that the learners are always engaged and learning in a hands-on fashion. Usually the expert will be the navigator, but there may be a point when the learners can even get into the navigation role and allow the expert to continue just as an observer that's around for consultation. If there comes a point where the expert is no longer necessary at all, this style may no longer be useful.

  • Recommended for: teaching/guiding many people the same thing at once.
  • Not Recommended for: groups that have graduated to having the teacher as an observer for an extended amount of time. Move on to something more engaging/efficient!

💡 Check out this great blog post written by Melissa Dirdo for more on ClassDojo's approach to mobbing.

Peer Mobbing

Peer mobbing is is a form of mob programming when everyone has roughly the same level of ability and it makes sense to rotate them into navigator/driver positions equally.

  • Recommended for: stuff the team is working though/learning together that they all want to know/understand. getting the team on the same page about practices/processes/conventions. working through a hairy problem that could use lots of different ideas/perspectives.
  • Not Recommended for: simple straightforward things. things that are low value for everyone to learn.

Divide and Conquer

If stories are sliced well vertically, a particular story may still have divisible parts along other lines that could allow them to be worked on simultaneously without much overhead. This requires that everyone involved gets in a group and does actual upfront planning and breakdown but it can be pretty quick ("You do the frontend and I'll do the backend", "You do the model and I'll do the controller"). This does not require any tracking whatsoever in asana (and probably shouldn't), so once things are broken up well vertically in asana, feel free to break up a particular story horizontally to collaborate on it if you think that's the best way. You'll probably want to solve integrations between layers first before actually building the layers. There may be other sub-pieces to cut out other than horizontal layers as well!

  • Recommended for: When everything is simple and straightforward and everyone knows what to do and how to do it. When everybody is exhausted from group programming and wants to just bang out some code and listen to Iron Maiden. When someone being mentored is ready to try flying solo to see if they really can apply their new learnings on their own.
  • Not recommended for: Work that can't be parallelized. Teams that don't have widespread capability on the subject matter (they're just going to continuously interrupt each other asking questions). Work that, when broken down, is not straightforward.

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