The Nexus framework

Nexus framework introduction

• Nexus is a framework for developing and sustaining scaled product delivery initiatives.
  • It builds upon Scrum, extending it only where absolutely necessary to minimize and manage dependencies between multiple Scrum Teams while promoting empiricism and the Scrum Values.
  • The Nexus framework inherits the purpose and intent of the Scrum framework as documented in the Scrum Guide (www.scrumguides.org.) Scaled Scrum is still Scrum.
  • Nexus does not change the core design or ideas of Scrum, or leave out elements, or negate the rules of Scrum.
  • Doing so covers up problems and limits the benefits of Scrum, potentially even rendering it useless.

Nexus Definition

• A Nexus is a group of approximately three to nine Scrum Teams that work together to deliver a single product; it is a connection between people and things.
• A Nexus has a single Product Owner who manages a single Product Backlog from which the Scrum Teams work.
• The Nexus framework defines the Accountabilities, Events, and Artifacts that bind and weave together the work of the Scrum Teams in a Nexus.
• Nexus builds upon Scrum’s foundation, and its parts will be familiar to those who have used Scrum.
  • It minimally extends the Scrum framework only where absolutely necessary to enable multiple teams to work from a single Product Backlog to build an Integrated Increment that meets a goal.

The Nexus framework purpose

• A Nexus has a single Product Owner who manages a single Product Backlog from which the Scrum Teams work.
  • Scrum.org has introduced the Nexus framework for this purpose with some difference with scaled Scrum.
  • Nexus contains 3-9 Scrum Teams and a Nexus Integration Team.

Nexus framework rule

• Each element of the framework serves a specific purpose that is essential to help teams and organizations scale the benefits of Scrum with multiple Scrum Teams working together.

Nexus framework use

• As organizations use Nexus, they typically discover complementary patterns, processes, and practices that help them in their application of the Nexus framework.
  • As with Scrum, such tactics vary widely and are described elsewhere.

Nexus Theory

• At its heart, Nexus seeks to preserve and enhance Scrum’s foundational bottom-up intelligence and empiricism while enabling a group of Scrum Teams to deliver more value than can be achieved by a single team.
• The goal of Nexus is to scale the value that a group of Scrum Teams, working on a single product, is able to deliver.
  • It does this by reducing the complexity that those teams encounter as they collaborate to deliver an integrated, valuable, useful product Increment at least once every Sprint.
  • The Nexus Framework helps teams solve common scaling challenges like reducing cross-team dependencies, preserving team self-management and transparency, and ensuring accountability.
    • Nexus helps to make transparent dependencies.
    • These dependencies are often caused by mismatches related to:
      • Product structure:
        • The degree to which different concerns are independently separated in the product will greatly affect the complexity of creating an integrated product release.
      • Communication structure:
        • The way that people communicate within and between teams affects their ability to get work done; delays in communication and feedback reduce the flow of work.
    • Nexus provides opportunities to change the process, product structure, and communication structure to reduce or remove these dependencies.
      • While often counterintuitive, scaling the value that is delivered does not always require adding more people.
      • Increasing the number of people and the size of a product increases complexity and dependencies, the need for collaboration, and the number of communication pathways involved in making decisions.
      • Scaling-down, reducing the number of people who work on something, can be an important practice in delivering more value.

The Nexus Framework

• Nexus builds upon Scrum by enhancing the foundational elements of Scrum in ways that help solve the dependency and collaboration challenges of cross-team work.
  • Nexus reveals an empirical process that closely mirrors Scrum.
• Nexus extends Scrum in the following ways:
  • Accountabilities :
    • The Scrum framework defines three specific sets of accountabilities within a Scrum Team : the Developers, the Product Owner, and the Scrum Master like in the Scrum Guide.
    • An additional accountability is introduced, the Nexus Integration Team.
      • The Nexus Integration Team ensures that the Nexus delivers a valuable, useful Integrated Increment at least once every Sprint.
      • The Nexus Integration Team consists of the Product Owner, a Scrum Master, and Nexus Integration Team Members (the appropriate members from the Scrum Teams).
  • Events :
    • Events are appended to, placed around, or replace regular Scrum Events to augment them.
      • As modified, they serve both the overall effort of all Scrum Teams in the Nexus, and each individual team.
      • A Nexus Sprint Goal is the objective for the Sprint.
  • Artifacts :
    • All Scrum Teams use the same, single Product Backlog.
      • As the Product Backlog items are refined and made ready, indicators of which team will most likely do the work inside a Sprint are made transparent.
      • A Nexus Sprint Backlog exists to assist with transparency during the Sprint.
      • The Integrated Increment represents the current sum of all integrated work completed by a Nexus.

Nexus Accountabilities

• A Nexus consists of Scrum Teams that work together toward a Product Goal.
  • The Scrum framework defines three specific sets of accountabilities within a Scrum Team : the Developers, the Product Owner, and the Scrum Master like in the Scrum Guide.
    • These accountabilities are prescribed in the Scrum Guide.
  • In Nexus, an additional Accountability is introduced, the Nexus Integration Team.

Nexus Events

• Nexus adds to or extends the Events defined by Scrum.
  • The duration of Nexus Events is guided by the length of the corresponding Events in the Scrum Guide.
  • They are timeboxed in addition to their corresponding Scrum Events.
• At scale, it may not be practical for all members of the Nexus to participate to share information or to come to an agreement.
  • Except where noted, Nexus Events are attended by whichever members of the Nexus are needed to achieve the intended outcome of the event most effectively.

Nexus events composition

• Sprint
• Cross-Team Refinement
• Nexus Sprint Planning
• Nexus Daily Scrum
• Nexus Sprint Review
• Nexus Sprint Retrospective

Nexus Artifacts and Commitments

• Nexus Artifacts represent work or value, and are designed to maximize Transparency, as described in the Scrum Guide.
  • The Nexus Integration Team works with the Scrum Teams within a Nexus to ensure that transparency is achieved across all artifacts and that the state of the Integrated Increment is widely understood.
  • Nexus extends Scrum with the following Artifacts, and each Artifact contains a commitment, as indicated below.
  • These commitments exist to reinforce empiricism and the Scrum value for the Nexus and its stakeholders.

Nexus Artifacts composition

• Product Backlog
• Nexus Sprint Backlog
• Integrated Increment

Caution

• As with the Scrum framework, the Accountabilities in Nexus, its Artifacts, Events, and Rules are immutable.
  • Although implementing only parts of Nexus is possible, the result is not Nexus.

Nexus Framework : Accountabilities

Nexus framework : Artifacts

Nexus framework : Events

Nexus framework : Rules

Scrum for Developers : Scrum PSD flashcards

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Updated : 03/09/2021