Scrum & Agile
Overview
Scrum is an agile framework for developing complex products through iterative, time-boxed sprints. Covered by the Scrum Foundation Professional Certificate (SFPC) from CertiProf.
Agile Manifesto
Values:
- Individuals and interactions over processes and tools
- Working software over comprehensive documentation
- Customer collaboration over contract negotiation
- Responding to change over following a plan
12 Principles: Customer satisfaction, welcome change, frequent delivery, collaboration, motivated teams, face-to-face communication, working software as progress, sustainable pace, technical excellence, simplicity, self-organising teams, regular reflection.
Scrum Framework
Roles
| Role | Responsibilities |
|---|---|
| Product Owner | Owns the Product Backlog; prioritises based on business value; defines "what" |
| Scrum Master | Facilitates Scrum; removes impediments; protects the team; servant leader |
| Development Team | Self-organising, cross-functional; builds the product increment |
Artifacts
| Artifact | Description |
|---|---|
| Product Backlog | Ordered list of everything that might be needed in the product |
| Sprint Backlog | Items selected for the current Sprint + plan to deliver them |
| Increment | Sum of all completed backlog items; must be "Done" and potentially shippable |
Definition of Done (DoD)
A shared checklist that defines when work is truly complete, e.g., code reviewed, tested, documented, deployed to staging.
Events
| Event | Duration | Purpose |
|---|---|---|
| Sprint | 1–4 weeks | Time-box to create a potentially shippable increment |
| Sprint Planning | ≤ 8 hrs (4-week sprint) | Select backlog items; create Sprint Goal and Sprint Backlog |
| Daily Scrum | 15 min | Inspect progress; adapt plan for next 24 hrs |
| Sprint Review | ≤ 4 hrs | Demo increment to stakeholders; update backlog |
| Sprint Retrospective | ≤ 3 hrs | Inspect team process; identify improvements |
User Stories
As a <role>, I want <feature>, so that <benefit>.
Acceptance Criteria:
- Given <context>, When <action>, Then <outcome>.
INVEST criteria: Independent, Negotiable, Valuable, Estimable, Small, Testable.
Estimation
- Story Points, relative effort (Fibonacci: 1, 2, 3, 5, 8, 13, 21).
- Planning Poker, team members vote simultaneously to avoid anchoring.
- Velocity, average story points completed per sprint; used for forecasting.
Common Mistakes
- Product Owner not available to the team.
- Scrum Master acting as a project manager (command and control).
- Carrying over incomplete items without re-estimation.
- Skipping the retrospective, it is the most valuable ceremony for improvement.
- Treating the Daily Scrum as a status report to management.
Interview Questions
Q: What is the difference between Scrum and Kanban? Scrum uses fixed-length sprints, defined roles, and a sprint backlog. Kanban is a continuous flow system with WIP limits and no prescribed roles or ceremonies. Kanban is better for operational work; Scrum for product development.
Q: Who can change the Sprint Backlog during a Sprint? Only the Development Team can modify the Sprint Backlog during a Sprint. The Product Owner can negotiate scope with the team, but cannot unilaterally add or remove items.
Cheat Sheet
Roles: Product Owner | Scrum Master | Development Team
Artifacts: Product Backlog | Sprint Backlog | Increment
Events: Sprint | Planning | Daily Scrum | Review | Retrospective
Story: As a <role>, I want <feature>, so that <benefit>
Estimation: Story Points | Planning Poker | Velocity