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.
Nexus Artifacts and Commitments
- 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
- Product Backlog
- Nexus Sprint Backlog
- Integrated Increment
Product Backlog
- There is a single Product Backlog that contains a list of what is needed to improve the product for the entire Nexus and all of its Scrum Teams.
- At scale, the Product Backlog must be understood at a level where dependencies can be detected and minimized.
- The Product Owner is accountable for the Product Backlog, including its content, availability, and ordering.
Product Goal
- The commitment for the Product Backlog is the Product Goal.
- The Product Goal, which describes the future state of the product and serves as a long-term goal of the Nexus.
Nexus Sprint Backlog
- A Nexus Sprint Backlog is the composite of the Nexus Sprint Goal and Product Backlog items from the Sprint Backlogs of the individual Scrum Teams.
- It is used to highlight dependencies and the flow of work during the Sprint.
- The Nexus Sprint Backlog is updated throughout the Sprint as more is learned.
- It should have enough detail that the Nexus can inspect their progress in the Nexus Daily Scrum.
Nexus Sprint Goal
- The commitment for the Nexus Sprint Backlog is the Nexus Sprint Goal.
- The Nexus Sprint Goal is a single objective for the Nexus.
- It is the sum of all the work and Sprint Goals of the Scrum Teams within the Nexus.
- It creates coherence and focus for the Nexus for the Sprint by encouraging the Scrum Teams to work together rather than on separate initiatives.
- The Nexus Sprint Goal is created at the Nexus Sprint Planning event and added to the Nexus Sprint Backlog.
- As Scrum Teams work during the Sprint, they keep the Nexus Sprint Goal in mind.
- The Nexus should demonstrate the valuable and useful functionality that is done to achieve the Nexus Sprint Goal at the Nexus Sprint Review in order to receive stakeholder feedback.
Integrated Increment
- The Integrated Increment represents the current sum of all integrated work completed by a Nexus toward the Product Goal.
- The Integrated Increment is inspected at the Nexus Sprint Review, but may be delivered to stakeholders before the end of the Sprint.
- The Integrated Increment must meet the Definition of Done (DoD).
Definition of Done
- The commitment for the Integrated Increment is the Definition of Done (DoD), which defines the state of the integrated work when it meets the quality and measures required for the product.
- The Increment is done only when integrated, valuable, and usable.
- The Nexus Integration Team is responsible for a Definition of Done (DoD) that can be applied to the Integrated Increment developed each Sprint.
- All Scrum Teams within the Nexus must define and adhere to this Definition of Done (DoD).
- Individual Scrum Teams self-manage (Scrum Self-Organization) to achieve this state.
- They may choose to apply a more stringent Definition of Done (DoD) within their own teams, but cannot apply less rigorous criteria than agreed for the Integrated Increment.
- Decisions made based on the state of artifacts are only as effective as the level of artifact Transparency.
- Incomplete or partial information will lead to incorrect or flawed decisions.
- The impact of those decisions can be magnified at the scale of Nexus.