What Happens in Each SDLC Phase?

The SDLC is a process to help accelerate the development, deployment, and operations of different applications. There are multiple phases of the software development lifecycle. In this blog, we will explore each phase of the SDLC lifecycle and gain a deep understanding of what these phases entail.

Phases of SDLC

An SDLC is crucial because it provides a structured framework for development, ensuring high-quality software is delivered efficiently. It reduces risks, minimizes errors, and improves collaboration among teams. By breaking the process into clear phases, SDLC helps optimize resource use, align software with business goals, and ensure user satisfaction. It’s the backbone of a reliable, predictable, and repeatable development process.

The different stages that are a part of the SDLC include:

• Planning: Define the project's purpose, scope, requirements, and resources. It’s the foundation for success, ensuring clear goals and realistic timelines.
• Design: Create blueprints for the system, including architecture, user interfaces, and database structures. This guides developers on what to build.
• Development: Turn designs into a functioning application by coding and integrating features. Collaboration and early testing are key here.
• Testing: Verify that the software works as intended, catching bugs, performance issues, or security vulnerabilities before deployment.
• Deployment: Launch the software for users, either fully or in stages. This ensures the product is live and operational.
• Maintenance: Support the software post-launch by fixing bugs, updating features, and ensuring long-term compatibility.

Let’s understand in depth what goes into all the phases mentioned above

Planning SDLC Phase

The planning phase of the Software Development Life Cycle (SDLC) is the initial stage where the groundwork for the entire project is laid. It involves understanding the project objectives, determining its feasibility, and outlining how to achieve the desired outcomes. This phase sets the stage for the subsequent stages of the SDLC by defining the scope, requirements, and goals of the project.

There are a few key activities that are involved in the Planning SDLC phase. Let’s take a look at these different activities.

• Requirement Gathering: Understand business objectives, technical requirements, and gather expectations, documents, and inputs from all relevant stakeholders
• Feasibility Checks: Assess the project's technical, operational, and financial feasibility and determine if it is achievable in the given time, budget, and resource constraints.
• Define Objectives: Define the project’s goals and success criteria and establish measurable KPIs.
• Risk Analysis: Identify potential risks and develop strategies to mitigate risks
• Project Planning: Create a project roadmap including milestones, timelines, deliverables, and define the roles and responsibilities of team members.

The key deliverables of the SDLC planning phase include a Project Charter, which outlines the scope, objectives, and key stakeholders; a Feasibility Report, assessing the project's viability; a detailed Project Plan, specifying timelines, resources, milestones, and budget estimates; and a Risk Management Plan, identifying potential risks and strategies to mitigate them. These deliverables ensure clarity, alignment, and a well-structured foundation for the project's success.

The planning phase of the SDLC is crucial as it lays the foundation for a project's success by defining objectives, scope, and requirements while ensuring alignment among stakeholders. It minimizes risks, prevents scope creep, and enables efficient resource allocation through thorough analysis and planning. By establishing clear roadmaps and feasibility studies, this phase ensures the project is set up for timely, cost-effective, and goal-oriented execution.

Design SDLC Phase

The design phase of the Software Development Life Cycle (SDLC) translates the requirements gathered in the planning phase into a clear and actionable blueprint for the development team. This phase focuses on creating the architecture and design specifications that define how the system will be built and function. It acts as a bridge between what the system needs to do (requirements) and how it will achieve those objectives (implementation).

There are a few key activities involved in the Design SDLC phase. Let’s take a look at these different activities:

• System Design Specification (SDS): Develop detailed design documents outlining the system’s architecture, data flow, interfaces, and key modules.
• Data Modeling: Create data flow diagrams (DFDs), entity-relationship diagrams (ERDs), or other models to define how data is structured and flows through the system.
• User Interface (UI) Design: Develop mockups or prototypes for the system's user interfaces to ensure a seamless user experience.
• Technology Selection: Choose the frameworks, programming languages, tools, and platforms required to develop the system.
• Integration Planning: Outline how different modules and external systems will interact to ensure seamless integration.
• Security Design: Define the security protocols, authentication mechanisms, and compliance measures to protect the system and its data.

The key deliverables of the SDLC design phase include a High-Level Design (HLD) document that describes the overall architecture and system design, a Low-Level Design (LLD) document that details specific components, modules, and their interactions, and Prototypes or Wireframes that provide a visual representation of the system’s interface. These deliverables ensure the development team has a clear roadmap for building the system efficiently.

The design phase of the SDLC is essential because it minimizes ambiguity, ensures a robust system architecture, and provides a clear plan for development. A well-executed design phase reduces the risk of costly changes in later stages, improves system performance, and ensures the final product meets the specified requirements effectively.

Development SDLC Phase

The development phase of the Software Development Life Cycle (SDLC) is where the actual coding and implementation of the system take place. This phase transforms the designs and plans created in the earlier phases into a working product or system. It involves writing, testing, and integrating code to build the system according to the design specifications and requirements.

There are a few key activities involved in the Development SDLC phase. Let’s take a look at these different activities:

• Code Implementation: Developers write code based on the High-Level Design (HLD) and Low-Level Design (LLD) documents using the selected programming languages, frameworks, and tools.
• Module Development: The system is divided into smaller, manageable modules that are developed independently and simultaneously by different teams.
• Version Control: Utilize version control systems (e.g., Git) to manage code repositories, track changes, and collaborate effectively.
• Unit Testing: Perform initial testing of individual modules or components to ensure they function as intended.
• Integration of Components: Combine and integrate all the developed modules to form a cohesive system, following the integration plan defined in the design phase.
• Documentation: Maintain technical documentation that describes the codebase, algorithms, and functionality of each module.

The key deliverables of the SDLC development phase include Source Code, which implements the system’s functionality, Unit Test Reports, documenting the results of testing individual components, and Updated Documentation that details the implementation process and technical specifications. These deliverables form the foundation of the system and ensure that it can be further tested, deployed, and maintained effectively.

The development phase is critical as it brings the project to life by translating design blueprints into a functional system. It ensures that the system is built according to specifications, adheres to quality standards, and is prepared for rigorous testing. A well-executed development phase results in a robust and reliable product that meets user and business needs.

Testing SDLC Phase

The testing phase of the Software Development Life Cycle (SDLC) ensures that the developed system meets the defined requirements and functions as expected. This phase focuses on identifying and resolving defects, validating performance, and ensuring the product is reliable, secure, and ready for deployment.

There are a few key activities involved in the Testing SDLC phase. Let’s take a look at these different activities:

• Test Planning: Create a test plan that outlines the testing strategy, objectives, scope, resources, and timelines.
• Test Case Development: Write detailed test cases that define inputs, execution steps, and expected outcomes for various functionalities.
• Unit Testing: Verify individual components or modules for correctness, often conducted during development.
• Integration Testing: Test the interactions between integrated modules to ensure they work together seamlessly.
• System Testing: Validate the system as a whole to check if it meets the requirements and performs as expected in a real-world environment.
• User Acceptance Testing (UAT): Conduct tests with end-users or stakeholders to ensure the system meets their needs and is ready for production.
• Bug Reporting and Fixing: Identify defects, log them in a tracking system, and ensure they are resolved and retested.

The key deliverables of the SDLC testing phase include Test Plans and Test Cases, which define the testing strategy and scenarios; Bug Reports, documenting issues found during testing; and Test Summary Reports, providing an overview of testing outcomes, defect status, and readiness for deployment. These deliverables ensure a thorough evaluation of the system's quality and functionality.

The testing phase is crucial as it helps identify and resolve issues before the product goes live, reducing the risk of failure in production. By ensuring the system is reliable, secure, and user-friendly, this phase improves user satisfaction and minimizes post-deployment maintenance costs. A well-executed testing phase guarantees a high-quality product that meets both technical and business expectations.

Maintenance SDLC Phase

The maintenance phase of the Software Development Life Cycle (SDLC) begins after the system is deployed and operational. This phase focuses on ensuring the system continues to function as intended, meets evolving user needs, and remains secure and efficient over time. It involves monitoring, updating, and enhancing the system based on feedback, performance data, and changing requirements.

There are a few key activities involved in the Maintenance SDLC phase. Let’s take a look at these different activities:

• System Monitoring: Continuously monitor system performance, usage, and error logs to identify potential issues or bottlenecks.
• Bug Fixing: Address any bugs or defects reported by users or detected during monitoring to maintain system reliability.
• Updates and Enhancements: Implement updates to add new features, improve performance, or adapt to changes in technology and business needs.
• Security Patches: Regularly update the system to address vulnerabilities and ensure compliance with security standards.
• Performance Optimization: Make adjustments to improve system speed, scalability, and resource efficiency as usage patterns evolve.
• User Support: Provide ongoing technical support to resolve user issues and ensure satisfaction.

The key deliverables of the SDLC maintenance phase include Bug Fix Reports, documenting issues resolved; System Updates and Patches, ensuring the system is up-to-date; and Performance Reports, analyzing system performance and highlighting areas for improvement. These deliverables help maintain the system's reliability and relevance.

The maintenance phase is essential as it ensures the system remains operational, secure, and aligned with business objectives over its lifecycle. It addresses user feedback, adapts to changing requirements, and mitigates risks, ultimately extending the system's longevity and maximizing its value to the organization.

Conclusion

The SDLC provides a systematic approach to building and managing software, with each phase playing a crucial role in ensuring project success. From the initial Planning Phase, where requirements are defined, to the Design Phase, which creates the blueprint, followed by the Development Phase, where the system is built, the Testing Phase, which ensures quality, and finally the Maintenance Phase, which keeps the system running smoothly, each step is essential.

Understanding these phases helps teams collaborate effectively, reduce risks, and deliver software that meets user needs and business goals. By adhering to this structured process, organizations can streamline their workflows and consistently achieve reliable, high-quality results.

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Siddhant Khisty

Siddhant is a Product Executive at Devtron with expertise in Kubernetes, ArgoCD, and DevOps. An organizer for Cloud Native Nashik, he loves open-source tech, automation, and securing deployments.