Mixing cultures provides a broader perspective

Scrumban is the combination of Kanban (lean) with Scrum (Agile) techniques. Each contributes different things to the hybrid framework. Kanban contributes a focus on flow, while Scrum contributes a focus on people and timeframe. Together, both focuses bring value to process improvement.

The flow focus describes how work moves through the development process.  The techniques that Kanban contributes include:

  • Visualization of Flow
  • Pulling Work Forward
  • Work-in-Progress Limits
  • Explicit Policies

Scrum describes how people interact and the timeframes for that interaction.  The techniques that Scrum contributes include:

  • Iterations
  • Bounded Teams
  • Retrospectives
  • Demonstrations

Both Kanban and Scrum have some similarities, such as:

  • Small units of work
  • Backlogs
  • Stand-up Meetings/Daily Interactions

In many organizations the differences between the two frameworks have been blurred already.  I observed a team that was using Kanban and wanted a mechanism to enforce the discipline of periodic feedback with their internal product team.  The product they produce has one primary release per year.  The development team negotiated with the product team to implement three week sprints bounded by a planning session and a hands-on demonstration.  In implementing sprints, sprint planning and demonstrations the team had veered from Kanban to Scrumban.  The team could have solved the feedback problem by implementing an internal release schedule, but the product team found the Scrum-based solution easier to understand and implement.

A second example I observed was a pure Scrum team that was struggling to identify the reason they were not completing user stories during every sprint. The team had identified the issue in multiple retrospectives, but had not had luck in determining a solution.  In the third retrospective they decided to use visualization of flow. They created a value chain map of their process.  During the next sprint they began tracking the flow of work on a paper Kanban board. This process made the problem very apparent. The team would begin a fairly large number of stories, and then late in the sprint, begin to have testers “test” the new code.  A bottleneck was created between testing and development.  The team solved the bottleneck by breaking stories into smaller parts, implementing WIP limits on development and then switching a developer to the testing role when the bottleneck began to appear.  This team veered away from pure Scrum to Scrumban to address a flow problem.

Combining Scrum and Kanban requires the team to take a broader process focus.  Kanban focuses on the flow of work.  The process of visualizing work helps to identify bottlenecks that slow the delivery of value.  Scrum focuses on how people interact.  Scrum puts people together in formal meetings and workspaces where interaction occurs.  Scrumban breaks the focus either on flow or on people to get the best of both frameworks.