Computer Science Basics Course (CS101) – Module 8
Module 8: Introduction to Software Development Lifecycle
- Overview of software development methodologies (Waterfall, Agile, Scrum)
Introduction:
Software development methodologies are frameworks that provide guidelines and processes for planning, designing, implementing, and maintaining software projects. Each methodology has its own set of principles, practices, and approaches to managing the software development lifecycle. In this lesson, we will explore three prominent software development methodologies: Waterfall, Agile, and Scrum.
- Waterfall Methodology:
Overview: The Waterfall methodology follows a linear and sequential approach to software development, with distinct phases executed in a predetermined order.
Phases:
Requirements Analysis
Design
Implementation
Testing
Deployment
Maintenance
Characteristics:
Emphasizes extensive planning and documentation upfront.
Progresses through each phase sequentially, with no overlapping or iteration between phases.
Changes to requirements or design are difficult to accommodate once the project moves to the implementation phase.
Advantages:
Clear structure and well-defined stages make it easy to manage and understand.
Suited for projects with stable and clearly defined requirements.
Disadvantages:
Limited flexibility to accommodate changes or adapt to evolving requirements.
Long development cycles may lead to delayed delivery and increased risk of project failure.
- Agile Methodology:
Overview: Agile methodologies prioritize flexibility, collaboration, and iterative development, focusing on delivering incremental value to users.
Principles (based on the Agile Manifesto):
Individuals and interactions over processes and tools
Working software over comprehensive documentation
Customer collaboration over contract negotiation
Responding to change over following a plan
Characteristics:
Emphasizes short development iterations (sprints) with frequent customer feedback and adaptation.
Values collaboration, teamwork, and communication among cross-functional teams.
Prioritizes delivering working software iteratively, enabling early and continuous customer feedback.
Advantages:
Greater flexibility to respond to changing requirements and customer feedback.
Enhanced collaboration and communication within development teams and with stakeholders.
Disadvantages:
Requires active involvement and commitment from all stakeholders throughout the project.
May lack sufficient documentation and long-term planning compared to traditional methodologies like Waterfall.
- Scrum Methodology:
Overview: Scrum is an Agile framework that provides specific roles, ceremonies, and artifacts to facilitate iterative and incremental software development.
Roles:
Product Owner: Represents the interests of stakeholders and prioritizes the product backlog.
Scrum Master: Facilitates the Scrum process, removes impediments, and ensures adherence to Scrum principles.
Development Team: Self-organizing cross-functional team responsible for delivering increments of working software.
Ceremonies:
Sprint Planning: Plan the work to be done in the upcoming sprint.
Daily Standup: Daily meeting to discuss progress, plans, and any impediments.
Sprint Review: Demo and review of the work completed during the sprint.
Sprint Retrospective: Reflect on the sprint and identify areas for improvement.
Artifacts:
Product Backlog: Prioritized list of features, enhancements, and bug fixes maintained by the Product Owner.
Sprint Backlog: Subset of items from the Product Backlog selected for implementation during the sprint.
Increment: Working product functionality produced by the Development Team during the sprint.
Advantages:
Clear roles, ceremonies, and artifacts promote transparency, collaboration, and accountability.
Iterative and incremental approach enables rapid adaptation to changing requirements and feedback.
Disadvantages:
Requires disciplined adherence to Scrum practices and principles for successful implementation.
May not be suitable for all types of projects or teams, particularly those with fixed deadlines or strict regulatory requirements.
- Understanding the software development lifecycle phases (requirements, design, implementation, testing, deployment, maintenance)
Introduction:
The software development lifecycle (SDLC) is a structured process used to design, develop, test, deploy, and maintain software applications. Each phase of the SDLC serves a specific purpose and contributes to the overall success of the project. In this lesson, we will explore the different phases of the SDLC and understand their significance in the software development process.
- Requirements Phase:
Purpose: Gather and document user requirements, business needs, and functional specifications for the software.
Activities:
Conduct stakeholder interviews and workshops to understand user needs and expectations.
Document requirements in a Requirements Specification document, including functional and non-functional requirements.
Validate requirements with stakeholders to ensure alignment with business objectives and user expectations.
Importance: Establishes a clear understanding of what the software should accomplish and forms the basis for subsequent phases.
- Design Phase:
Purpose: Define the architecture, system components, and technical specifications for the software.
Activities:
Develop high-level and detailed designs, including system architecture, data models, user interfaces, and software components.
Create design documents such as system architecture diagrams, data flow diagrams, and wireframes.
Review and refine designs to ensure feasibility, scalability, and alignment with requirements.
Importance: Provides a blueprint for the implementation phase and guides developers in building the software solution.
- Implementation Phase:
Purpose: Develop, code, and build the software according to the specifications and designs created in earlier phases.
Activities:
Write code using programming languages, frameworks, and development tools specified in the design phase.
Integrate software components and modules to create a functional system.
Conduct code reviews, unit testing, and debugging to ensure code quality and reliability.
Importance: Transforms design concepts into working software, laying the foundation for testing and deployment.
- Testing Phase:
Purpose: Verify and validate the software to ensure it meets quality standards, functional requirements, and user expectations.
Activities:
Develop test plans, test cases, and test scripts based on requirements and design specifications.
Execute various types of testing, including unit testing, integration testing, system testing, and acceptance testing.
Identify and report defects, bugs, and issues, and collaborate with development teams to resolve them.
Importance: Ensures the software is free from defects, meets quality standards, and delivers the intended functionality to end users.
- Deployment Phase:
Purpose: Deploy the software into the production environment and make it available for end users to use.
Activities:
Prepare deployment packages and release notes documenting changes and updates.
Coordinate deployment activities with operations teams, system administrators, and stakeholders.
Monitor and troubleshoot deployment issues, ensuring a smooth transition to the production environment.
Importance: Makes the software available for use by end users, marking the culmination of development efforts.
- Maintenance Phase:
Purpose: Support, maintain, and enhance the software over its lifecycle to address issues, add new features, and adapt to changing requirements.
Activities:
Provide ongoing technical support, bug fixes, and software updates to address issues reported by users.
Enhance the software based on user feedback, changing business needs, and technological advancements.
Monitor performance, security, and scalability, and optimize the software as needed.
Importance: Ensures the longevity, reliability, and continued value of the software to users and stakeholders.