Ultimate Guide to the Software Development Lifecycle: Best Practices for Tech Innovators

What is the software development lifecycle (SDLC)?

The Software Development Life Cycle (SDLC) is a systematic approach to developing software applications. It is a big-picture breakdown of all steps involved in software creation. Well implemented SDLC should always result in high quality product. Whereas, delving into software development without a well-crafted plan is a recipe for overbudgeting, delays, and costly failures. During the early days of computing, software development was largely unstructured, as programmers mostly wrote code without having well-defined processes. Since the 1970s concepts of Software Development Life Cycle (SDLC) started to take shape with the introduction of the Waterfall Model. Consequently, as years went by, other models emerged, sharing common principles. Understanding SDLC and different models is crucial for organizations aiming to adopt best practices in their software development journey.

Who needs to know about the Software Development Life Cycle (SDLC)?

If a company uses Software Development Life Cycle (SDLC) principles, it’s important for individuals beyond developers, engineers, and project managers to have a basic understanding of how it works. Many stakeholders might be involved in various stages, making awareness essential for all. Therefore, in short, everyone should know about it.

However, one of the key factors influencing success or failure in software development is a cross-functional, skilled team comprised of various roles and specializations. Consequently, these will be outlined in more detail:

  • Product Owner. The Product Owner represents business and its needs, working closely with end users to create and prioritize product backlog. They ensure that all functionalities needed from a business perspective are delivered in a timely manner.

  • Business Analyst. The Business Analyst gathers and analyzes requirements, ensuring that the needs of the business are clearly understood and effectively communicated. They liaise with both the client and the development team to identify requirements and discuss potential solutions that meet the criteria.

  • Project Manager. Their role is to simply manage the project. Like the Business Analyst, they can be involved in communication with clients; however, their responsibilities are typically more aligned with collaborating closely with the development team. They allocate tasks, monitor progress, oversee the development process, and coordinate team activities.

  • UI/UX Designer. Their main responsibility is to create a visually interesting, catchy interface and to ensure great user experience.

  • Developer. They are the core of a team. They can have significantly different areas of expertise between each other. Main responsibility of a developer is writing and implementing code based on provided design specification. In other words, they turn ideas into actual products. They also participate in code reviews and testing.

  • QA Specialists/Testers. They are responsible for designing and executing tests to identify defects. Depending on testing methodology they go through the software and ensure that the produced software meets product requirements. If software testing is lacking or done badly it could result in negative user experience and overall failure of the project.

These are the main roles of Software Development Life Cycle (SDLC). They can be called differently, but the main principles remain the same. Depending on the size of the team, these roles can often intertwine, allowing for greater flexibility and collaboration throughout the development process.

How the Software Development Life Cycle (SDLC) works, its Stages and Best Practices?

Software is a complex product developed and delivered through a series of steps. And every software development project starts the same way – with an idea. The idea then becomes a document, diagram or a prototype before eventually evolving into something accessible to the user. Every time, with each step, the output created in one step becomes the input to the next step. The process of software development is never-ending. The first release of a software application is rarely complete. There are almost always new features to add and bug fixes to be made. Moreover, once code is deployed, and software is available to the users, there will almost always be issues to be found, or new improvements to be made. These then become new features, bug fixes, and improvements to your product.

Software Development Life Cycle (SDLC) Stages

The Software Development Life Cycle (SDLC) is a structured methodology for software creation, guiding the development process from inception through to deployment and maintenance. Typically, the Software Development Life Cycle (SDLC) comprises between six and eight stages, depending on whether certain steps are combined or treated separately. Various Software Development Life Cycle (SDLC) models exist, each employing slightly different approaches to progressing through these stages. Despite the diversity in structuring, this article will explore six distinct stages, each fulfilling a unique role within the lifecycle. This systematic framework enables teams to successfully plan, design, build, test, and maintain their software.

Stage #1 Planning and Analysis

The initial phase of the Software Development Lifecycle (SDLC) is planning. The specifics of the planning process will vary, primarily based on whether the endeavor involves a new software project or the continuation of an existing one. For a new project, the emphasis lies in transforming the conceptual idea into a tangible reality. In contrast, an ongoing project requires the team to address the question, "What are the current issues?" Regardless of the project's nature, the success of this stage hinges on a thorough comprehension of stakeholder input, effective distribution of key tasks, meticulous planning of essential resources, and the clear delineation of responsibilities. Also, in this stage it is crucial to define requirement specifications for product. The better the software project is planned, the lower the risk of project failure, overspending and delays.

Stage #2 Software Design

The next stage is software design. This stage of Software Development Life Cycle (SDLC) starts by turning the software specifications into design plan called the Design Specification. It requires a lot of creativity and clarity. This stage encompasses the overarching high-level technical design of the product, as well as the design of data structures and databases. For those with a passion for engineering, this can be a particularly exhilarating phase due to the extensive problem-solving it entails. Although no tangible product is produced at this moment, the stage is of highest importance, as failure here can precipitate the complete collapse of the project.

Stage #3 Implementation

The subsequent stage is implementation. This is the most important part of the software development project as this is where the actual development starts. During this stage, a team of developers is assigned to the project, and all tasks are subdivided to achieve the outcome. Key components of this phase typically include, but are not limited to:

  • Choice/Definition of Architecture

  • Coding

  • Debugging

  • Developing Tests

  • Many more small tasks in between...

Success in this stage largely depends on the technical proficiency of the team, their work ethic, and the effectiveness of progress monitoring.

Stage #4 Quality Assurance/Testing

Once development is complete, the next stage focuses on verifying and testing that the developed product aligns with the specifications and is free from defects and deficiencies. This critical phase is typically handled by a dedicated testing team, although in smaller teams, it may be undertaken by the development team or even the broader project team. This stage involves executing a comprehensive set of test cases to ensure the software can be thoroughly verified and debugged prior to launch. If any issues are found,  they are fixed until the product meets the original specifications. If this stage is completed thoroughly and comprehensively, it can eliminate any possible post-launch issues.

Stage #5 Deployment

Once it is verified that the software is of the acceptable quality level it can be deployed. At this stage, the goal is to deploy the software to the production environment. Simply put, software is made available for customer use. It can be further split into stages and smaller tasks. Additionally, at this stage, user manuals and instructions videos can be created and released. The deployment phase, in essence, marks the software's debut in the spotlight, where it shall be judged by the most exacting critics of all - the end users.

Stage #6 Support & Maintenance

Once software is deployed for the end users – the development cycle does not end here. From time-to-time users will face problems using the software and those problems will need to be solved by either a dedicated support team or the people who developed the software. If the client requests new features, modifications or finds annoying bugs, the product will have to go through all the phases of Software Development Lifecycle once again.

How does Software Development Life Cycle (SDLC) address security?

A common issue in the Software Development Life Cycle (SDLC) is that security related activities are not addressed until the testing phase or even worse the maintenance phase. And to be even more pessimistic, in those stages they are done superficially and often lack depth. An easy way to integrate security in your SDLC process is to consider security concerns at every phase and to include security aspects in the requirements specifications. This can reduce the risk of security issues appearing unexpectedly. And make sure that everybody involved in the software development process is responsible for security.

How can DevSecOps be integrated into Software Development Life Cycle (SDLC)?

As mentioned earlier, many teams do not implement security aspect until later stages of the SDLC process. By implementing DevSecOps organizations reduce the risk for security breaches and vulnerabilities. Eventually, increasing overall efficiency and productivity by not having to deal with security issues when the house is on fire. By following steps outlined below organizations can easily integrate DevSecOps in their SDLC:

  1. Understand your current SDLC. This includes identifying currently used tools, technologies and methodologies utilized in software development.

  2. Analyze your development environment. This includes reviewing your infrastructure, applications, dependencies, data, etc., for vulnerabilities and understanding potential attack modes and channels.

  3. Analyze non-production/test environments for security risks. This can contain sensitive data or credentials that can be more easily stolen. By performing security analysis on development and testing environments organizations can reduce the risk of potential breaches or unauthorized access.

  4. Integrate security testing. This includes either designing several security related test cases or using automated security testing tools and processes to identify and address vulnerabilities in a timely manner.

  5. Implement security into each stage of the SDLC. This involves adding the security aspect from initial conception to the maintenance.

  6. Define clear roles. This involves establishing accountability for security issues throughout all stages of the SDLC.

  7. Provide continuous security training. This mainly involves continuously training developers, cybersecurity experts, testers and operations teams in aspects of best security practices, emerging threats, new technologies and new trends.

Software Development Life Cycle (SDLC) Examples

Waterfall Model

Waterfall model is a linear sequential cascade model representing the software development process as clear steps. As mentioned earlier, it dates to the 1970s. Every phase in this model only starts when the previous is finished. The project team is not allowed to go back and make any required changes. This model usually indicates strict documentation. It is best suited for projects that have steady requirements and clear vision with instant development.

Agile Model

Agile model blends both incremental and iterative approach that fits with all flexible requirements of a modern business. It dates to February 11th, 2001, when Agile Manifesto was created. Agile methodology allows teams to divide the whole process into subparts and iterations. These small parts are called sprints, where each team member is given certain tasks to be completed within a set timeframe. In this model, the whole team monitors the progress and re-evaluates priorities within backlog to ensure smooth product launch. Agile model is best suited for software projects that have high customer involvement and rapidly moving industries.

Iterative Model

Iterative model is based on a recurring pattern of launch and update. This model finds its roots back in the 1960s as part of NASA’s project Mercury. The main idea behind this model is that operates in repeated cycles, enabling creation of new versions quickly with less cost. Every iteration or phase in this software development model generates a new and improved version of the software. It is most suited for large-scale complex projects and for projects depending on web services and microservices.

Lean Model

Lean model concentrates on reducing the consumption of resources and time, optimizing workflow and reducing unnecessary inventory. Its use in software development dates back to 2003 with the release of a book Lean Software Development: An Agile Toolkit. It includes different steps in identifying value, mapping value stream, and making improvements. Essentially, it is very similar to the agile model. The biggest difference being that Agile model takes customer satisfaction as the top priority whereas the Lean model is mostly focused on waste and inefficiency elimination. It is best suited for companies seeking fast development speed and optimized workflows.

V-Shaped Model

V-Shaped model is essentially an extension of the Waterfall model. It dates to the late 1980s. This model comprises of two phases - verification and validation. The verification part encompasses requirements analysis, system design, architectural design, module design. The validation part encompasses unit testing, integration testing, system testing, and user testing. In this model, the process escalates upwards, and every development process must go through a testing phase before it is ready to move up. It is commonly used in governmental software projects.

 

Big Bang Model

It is the simplest Software Development Life Cycle (SDLC) model because it completely skips the planning part. This model entails concentrating all available resources and tools in software development and coding. The requirements here are understood and implemented as they arise in this model. It is great for very small teams and projects where requirements are not clear, and the product is relatively simple.

Spiral Model

The spiral model revolves around early identification and elimination of project risks. It was first described in 1986. It adopts a few different elements of different models, but in spiral model four primary activities are: risk planning, risk analysis, prototype building, assessment of deliverables. In spiral model the project starts with risk assessment to define work and after first iteration, the team then decides how the project can be improved. This model is most appropriate for enterprise software development and research projects.

Scrum Model

Scrum model draw its inspiration from Agile methodology. Scrum model has appeared in the early 1990s. It is characterized by frequent deliveries, collaboration and development cycles called Sprints. Main phases of this software development life cycle are Sprint planning, Sprint execution, Sprint review meetings, retrospective and release. Scrum strength lies in an idea that the who process can be broken down into short-term goals  and completed in short period. For scrum to be successful collaboration and communication among team members is essential. This model is best suited for medium-sized software projects.

Which Software Development Life Cycle (SDLC) model is the best?

There is no one best Software Development Life Cycle (SDLC) model. Choosing the right Software Development Life Cycle (SDLC) model is a strategic decision that will depend on project requirements, scope, team expertise, and end-goals. Each model has its pros and cons. The important part here is to align the chosen model with the size and characteristics of the project. Ultimately, the best model is the one that best fits the unique needs of the software project.

What is the most commonly used Software Development Life Cycle (SDLC) model?

Agile model is the most commonly used Software Development Life Cycle (SDLC) model. It provides very high degree of flexibility, and it is suitable for complex projects that evolve rapidly. It encourages collaboration between cross-functional teams, allows fast feedback and delivers high-quality software. Moreover, it promotes early and continuous delivery.

Benefits of the Software Development Life Cycle (SDLC)

Main benefit of Software Development Life Cycle (SDLC) is that it helps teams manage their software development and deliver top-notch software products that meet their client requirements. But that is not all. Other benefits include:

  • Allows highest level of management and documentation

  • Visibility of all processes

  • Provides single product vision for all stakeholders

  • Allows for predictable results in terms of time, costs, deliverables

  • Reduces the risk of failure

All in all, it mentally drives the team to be more oriented towards results. Which means that there will be less wasted effort and higher chance of success.

Conclusion

Software development is a complex process in a majority of cases. If the company does not employ SDLC principles it will be difficult to harness the chaos and prevent failure. MatrixALM provides a robust and organized system to manage and document the entire software development lifecycle. You may find all the features you need in MatrixALM, and if not there are plenty of integrations with additional tools that will accelerate your software development needs. Additionally, our Marketplace platform contains several predefined project templates for implementation of different SDLC models. If you would like to learn more, please don't hesitate to book a demo!

About the Author
Ignas Žakaitis
Software Testing Engineer