SOFTWARE DEVELOPMENT LIFE CYCLE

SDLC: is a structured process used to plan, design, develop, test, deploy,and maintain software. It ensures a systematic workflow and helps align software development with business goals and user requirements.

PHASE 1: REQUIREMENT/PLANNING This stage determines whether the project is technically, financially, and operationally feasible.

1. Activities: Feasibility analysis, cost estimation, scheduling, resource planning
2. Output: Project Plan, Feasibility Report
3. Key Roles: Project Managers, Senior Engineers, Stakeholders.

PHASE 2: ANALYSIS Detailed functional and non-functional requirements are documented clearly and approved by stakeholders.

1. Activities: Requirement gathering, validation, documentation.
2. Output: Software Requirement Specification (SRS).
3. Key Roles: Business Analysts, Product Owners.

PHASE 3: SYSTEM DESIGN The approved requirements are transformed into a technical blueprint for implementation.

1. High-Level Design (HLD): Defines system architecture, technology stack, database design, and major modules.
2. Low-Level Design (LLD): Specifies component logic, APIs, data structures, and workflows.
3. Output: Design Document Specification (DDS)

PHASE 4: DEVELOPMENT Developers build the software based on the approved design.

1. Activities: Coding, code reviews, unit testing, version control management.
2. Tools: IDEs, version control systems, debuggers.
3. Output: Source code, executable application.
4. Key Roles: Frontend, Backend, Full Stack Developers.

PHASE 5: TESTING Ensures the software meets requirements and is free from defects before release.

1. Unit Testing: Verifies individual components
2. Integration Testing: Ensures modules work together
3. System Testing: Validates the complete system
4. User Acceptance Testing (UAT): Confirms business requirements are met

PHASE 6: DEPLOYMENT The tested software is released to users.

1. Activities: Production setup, deployment, smoke testing
2. Modern Approach: Continuous Integration and Continuous Deployment (CI/CD) pipelines for faster and reliable releases
3. Output: Live application
4. Key Roles: DevOps Engineers, Release Managers

PHASE 7: MAINTENANCE Post-deployment support ensures long-term usability.

1. Activities: Bug fixes, performance tuning, updates, feature enhancements
2. Output: Patches, updates, new versions
3. Key Roles: Support Engineers, Developers

TEST-DRIVEN DEVELOPMENT: is a Software development method in which you write Automation Tests before the actual development process starts, which is coding.

BUG REPORT: in software testing because it ensures clear communication between testers and developers. It helps in faster identification, tracking, and resolution of defects, improving overall software quality.