Software Development Life Cycle

• What is a software

  A set of instructions that the system understands and makes it to perform some operations.

• SDLC stands for Software Development Life Cycle.

  Broadly 6 phases of development

  // the ‘Who’ of each phase depend on the scope of entire project

  • Requirement Gathering and Analysis Phase

    • Goal

      Document functional and non-functional requirements

      • Functional requirements specify What the software/product should do.
      • Non-functional requirements specify how the software/product should behave like
        • Response Time
        • Accessibility
        • Availability
        • Scalability
        • Maintainability
        • Extensibility …

    • Who

      • Business Analyst
      • Business user or Functional Users
      • Architect(s)
      • Lead Developer
      • Project Manager or Scrum Master
        • They coordinate the project / application
        • A project will have a definite start and definite end.

    • Process

      • Techniques
        • Understand the existing system or process
        • Discussion with the stake holders
        • Interview end users and stake holders
        • Questionnaire
        • Workshops
        • SMART // certain indicators on how the requirements should be
          • Specific
          • Measurable
          • Agreed by all stakeholders
          • Realistic
          • Time bound
        • Screen / Visual Prototypes

    • Deliverables

      • Use Cases
      • Identified Actors/Users
      • Screen Prototyping
      • UX designs
      • Reviewed and Approved Requirements
  • Design Phase

    • Goal

      Develop a system architecture/design based on the reviewed and approved deliverables. i.e., functional and non-functional requirements.

    • Who

      • Lead developer(s)
      • Architect(s)

    • Process

      • Design discussion
      • Refer phase one deliverables
      • Design Patterns references - general reusable solutions to recurring problems
      • Architecture references

      // experience and knowledge of persons involved plays a key role in this phase.

      // design should be within the scope of the functional and non-functional requirements

    • Deliverables

      • Database designs
        • Conceptual
        • Logical
        • Physical
      • Integration / API / Endpoint designs
        • example of optional google login in site login page to integrate login.
      • Application design
        • language used, databases ..
      • Infrastructure design
        • configuration of server
      • Reviewed and Approved design
  • Development of Coding Phase

    • Goal

      Develop actual software based on the design deliverables

    • Who

      • Developers(s)
      • Lead Developer(s)

    • Process

      • review the design by developers
        • address doubts and clarify design before implementation
        • have an open mind
        • have a positive attitude and be open to ideas and recommendations
        • create a harmonious environment
      • Code based on design(s)
      • Unit test the code

    • Deliverables

      • completed software development
      • reviewed and approved software programs / coding.
  • Testing or Quality Assurance Phase

    • Goal

      Perform software testing based on functional and non-functional requirements.

    • Who

      • Tester(s)
      • Lead tester(s)
      • Load and performance testers

    • Process

      • inputs are functional and non-functional requirements and developed code
      • develop and execute unit test cases
        • manual use case execution
      • develop and execute integration test cases (if there is any)
      • develop and execute load and performance test cases
      • user acceptance testing
        • Business / functional users will be given beta access and test the product

    • Deliverables

      • Completed development and execution of test cases
      • Reviewed and approved test results
  • Deployment Phase

    • Goal

      Moving the developed software to production environment so that end users can access it.

    • Who

      • Software configuration manager (SCM) // will deploy
      • Lead Developer
      • Infrastructure team
      • Project Manager / Scrum Master
      • User

    • Process

      • Project manager / Scrum master coordinates the deployment plan with all stakeholders
      • set up deployment date
      • move the software to production
      • test the live application by end user

      // the best practice is always to have a backup plan

      // also perform one type of testing in production

    • Deliverables

      • software application available in production to end users
  • Maintenance or Support Phase

    • Goal

      fix software bugs or issues that are identified in live software during usage by end user.

    • Who

      • Developer(s)
      • Lead developer(s)
      • Users

    • Process

      • recreate the issue and review
      • update and test the code / configuration / software program and resolve the issue
      • document the issue and fix

    • Deliverables

      • Updated production build