Scaled Agile Framework (or SAFe) is an agile software development framework consisting of a knowledge-base of integrated patterns intended for enterprise-scale Lean-Agile development. SAFe is scalable and modular, allowing an organization to apply it in a way that suits its need.
SAFe is a framework meant to cover the entire organization. The current version is SAFe 4.5. It has 4 levels; Portfolio, Large Solution, Program and Team. The Team level works very much like standard scrum. At this level, there is an Agile team which is cross functional and works together to deliver working systems every two weeks which are called iterations. The content of the iteration is determined by the Product Owner who is in charge of the team backlog. The iteration starts with a team planning meeting in which the team decides what user stories they can deliver by the end of the iteration. Each day the team meets in a daily standup meeting to discuss the progress and at the end of the iteration they demo their results to the Product Owner to make sure they have delivered the desired results. The team then conducts a retrospective to determine what they can improve for the next iteration before starting the cycle again with a new planning meeting. All of this is guided by a Scrum Master who makes sure the team works smoothly within the process and that it keeps improving.
The Program level is very similar to the Team level. The Program is comprised of multiple Teams working to deliver a larger system together. The Program ranges from 50 to 125 people. This team of teams is called an Agile Release Train or ART. It will also time-box it’s effort into Program Increments or PI’s which are 5 iterations by default. The content for each PI is determined by a Product Manager in the Program Backlog in the form of Features. This will provide most of the content for the Team Backlogs. The ART is governed by the RTE or Release Train Engineer. This role acts as the trains Scrum Master ensuring that it runs smoothly and stays on track. He is somewhat of the Program Manager at the Program Level. Each PI begins with a planning meeting in which all members of the teams get together to hear the Vision and Roadmap of the train and the features for the upcoming PI. Each team then plans what objectives they can achieve in this PI. They also identify dependencies with other teams on the train as well as risks. The teams commit to these PI objectives as a group providing visibility to Business Owners and Customers of what they can expect to be delivered in this PI.
To make sure the train will meet its objectives, we have both a bi-weekly meeting of the Scrum Masters and the Release Train Engineer to ensure all are on the same page and everything is on track. At the end of the iteration, a system demo is delivered. This is a demonstration of the integrated system. This ensures that we don’t have one team running ahead but that the whole train is iterating together. Adequate architecture and infrastructure is needed to ensure the trains are running as fast as possible. Each PI serves as a time to lay down the track for what we think we will need in order to achieve our goals in the following PI. This is called the Architecture Runway and it is facilitated to by the trains System Architect.
Each PI is 5 iterations long, but only 4 iterations are planned. The fifth iteration is called the IP iteration or Innovation Planning iteration. The iteration part is for the team engage in creative ideas like hackathons. Within the Planning part, three things occur; a) demo our accomplishments, b) maintenance for the train by retrospective on how to improve collaboration, c) plan next PI together. The IP also serves as an estimating guard-band to make sure the teams deliver on their commitment.
The Large Solution level provides the means to coordinate ARTS who are building even larger solutions in which a single ART can’t deliver by itself. At this level Solution Management is the content authority. The Value Stream Engineer is the coach and guide and a Solution Architect to help ensure good architecture is used. The Value Streams run the same PI cadence as the ARTS and has Planning, Solution Demo, and Inspect and Adapt for cross-ART capabilities.
The Portfolio Level is somewhat different than the other levels. Portfolio Management helps dictate direction for all underlying Value Streams by deriving Strategic Themes from the Enterprise Strategy and then allocates budgets to Value Streams to support these Themes. They also manage cross Value Stream initiatives which impact several solutions in the form of Epics.
See interactive SAFe Big Picture from here
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