A Guide to the Software Development Life Cycle

Understand how risks to projects from open source software can be managed through Software Composition Analysis.

What is the software development life cycle?

The software development life cycle (SDLC) is a series of steps used to develop and maintain software systems. But it’s not limited to creation; it can also be used when changing existing software.

It provides a framework for ensuring that software is developed in a structured and organized manner, focusing on reliability and improving quality. Utilizing the SDLC helps ensure that software meets the needs of its users and stakeholders and is delivered on time and within budget.

What are the stages of the SDLC?

While it’s essential to remember that the stages might differ depending on the team, seven steps are the foundation of any software development life cycle. These are:

  1.  Planning

  2.  Requirement analysis

  3.  Design

  4.  Implementation

  5.  Testing and debugging

  6.  Deployment

  7.  Maintenance


1. Planning

A project’s plan generally consists of:

  • Goals

  • Objectives

  • Scope

  • Necessary resources

  • Potential risks

  • Mitigation strategies

Based on this information, the development team can determine a timeline, a budget, and a list of key deliverables. This plan will serve as the foundation for the rest of the project, helping the team stay focused and on track as they move through the later stages. Typically, a Software Requirement Specification document is created for the requirement analysis phase.


2. Requirement analysis

In this phase, the project team works to understand the needs and requirements the software is being developed to satisfy. This might involve:

  • Conducting user research.

  • Gathering and documenting requirements.

  • Developing a high-level design for the software.

These tasks are completed through discussions with shareholders, customers, and business analysts. The results will guide the detailed design phase.


3. Design

This is where the software’s architecture, user interface, and data model are designed. This phase also includes creating technical specifications and identifying the components and modules necessary for building the software.


4. Implementation

In this phase, the software developers build the software based on the design and technical specifications. It typically involves:

  • Writing code.

  • Creating and configuring the development environment.

  • Integrating different components and modules into the overall system.


5. Testing and debugging

The project team tests the software to ensure it meets the previously discovered needs and requirements and is free of bugs. The testing phase usually involves manual and automated testing of the software’s performance, security, and reliability.

During this stage, the software is subjected to several tests, which include evaluating code quality, conducting unit testing and integration testing, and ensuring security.


6. Deployment

The team deploys the software to the production environment, where real users will use it. This typically involves creating and executing a deployment plan that outlines the steps and procedures for installing and configuring the software. This phase may involve installing the software on the user's computers or devices or making it available through a web-based platform.


7. Maintenance

The team continues to support and maintain the software after deployment. This process might involve:

  • Fixing any bugs or defects discovered.

  • Adding new features or functionality.

  • Providing technical support to users.

These steps are not always performed in a linear order, and individual steps might be iterated multiple times throughout the project. Different software development methodologies will have slightly different versions of the SDLC, with different names for each phase or even different steps entirely.

What are the advantages of the SDLC?

As previously mentioned, the software development life cycle helps improve the efficiency, reliability, and effectiveness of the development process.

When discussing its most significant benefits, the SDLC:

  • Provides a structured and organized approach to software development, which helps to ensure that the process is consistent and predictable.

  • Helps identify and evaluate potential risks.

  • Helps develop mitigation strategies.

  • Helps ensure that software meets the user's needs and requirements.

  • Provides a framework for communication and collaboration among team members.

  • Helps ensure that delivery is on time and within budget.

  • Helps ensure that software is high-quality and free of defects.

  • Provides a basis for ongoing maintenance and support.

What are the challenges of the SDLC?

Organizations that want to implement the SDLC framework might struggle with:

  • Time and cost, especially if the development method leaves zero room for flexibility or iteration.

  • Adapting to changing requirements or business needs is difficult, especially if the software development method is not agile.

  • Managing and coordinating the work of a large and diverse project team.

  • Determining the documentation and reporting level needed for a project.

  • Determining the software development method for a particular project.

  • Ensuring that software is developed in a manner that is consistent with industry standards and best practices.

Most popular SDLC models

As briefly discussed, there isn’t a one-size-fits-all SDLC method. To manage the unique needs various organizations might have, several SDLC models were developed, with the most commonly used ones being:

  • The Waterfall Model - the most widely used SDLC method is the Waterfall Model, which follows the linear part where the next phase begins once the previous stage ends. Its phases typically involve requirements collection & analysis, system design, coding and implementation, testing, deployment, and maintenance.
  • Agile - in the Agile model, the project is divided into smaller increments of work called “sprints,” which last for about two to four weeks. The Agile method offers developers a lot of flexibility and speed while also allowing them to quickly adapt to any changes.
  • Iterative Model - similar to the Agile method, the Iterative Model breaks down the project into smaller parts called iterations. Each iteration goes through a full SDLC cycle, where feedback from each iteration is then used to improve subsequent stages.
  • Spiral Model - such a method combines an iterative approach with risk assessment. The Spiral Model includes four repeatedly cycling phases - planning, risk assessment, development, and evaluation. This model works best in comprehensive projects.
  • V-model (validation & verification) - this method is an extension of the Waterfall Model, adding a testing phase to each corresponding development stage. This ensures the software is thoroughly tested before the next phase begins, reducing the risk of potential future bottlenecks.

What are software development life cycle best practices?

  • Develop a clear and detailed plan for the project, including goals and objectives, a timeline, and the resources needed.

  • Identify and evaluate potential risks and develop strategies to mitigate them.

  • Gather and document detailed user requirements and ensure that the software meets them.

  • Use an agile software development method that allows for flexibility and iteration.

  • Communicate and collaborate effectively with the project team and stakeholders.

  • Use automation and testing tools to improve the efficiency and reliability of the software development process.

  • Monitor and track the project's progress and adjust the plan as needed.

  • Follow industry standards and best practices for software development.

By following the seven stages of the SDLC and applying best practices, organizations can improve collaboration among team members, reduce the risk of errors and omissions, and improve the overall quality of their products.