How do developers make sure their applications meet all specifications? When do they test their code? What is the appropriate time frame for requirement analysis?
Without answers to these questions, software developers would be at a loss whenever they worked on a new project. How would they know what to do and when? That’s where the Software Development Life Cycle (SDLC) comes in.
In this guide, we’re going to discuss the essentials of SDLC. We’ll talk about each phase of SDLC and provide you with examples of how the life cycle is used in practice.
What is SDLC?
The Software Development Life Cycle is a methodology which outlines how you should approach software development. This process ensures you’re building software in the right order and helps make development more efficient.
The Software Development Life Cycle is important in project development because it allows everyone on a project team – from managers to developers – to keep track of a project. Team members only need to understand the basics of the life cycle to get an accurate idea of a project’s progression and when parts or all of it will be completed.
The Software Development Life Cycle is useful because it clearly outlines which activities occur during specific parts of the development process. If you’re new to coding, having a clear understanding of what you need to do and when, and what deliverables are due and when, is very beneficial.
The Software Development Life Cycle is typically overseen by a project manager who ensures developers meet their goals.
How Does SDLC Work?
The Software Development Life Cycle has seven stages to outline how a software project should be developed. While everyone has their own name for each stage of SDLC, here are the main themes you will see across the life cycle:
- Analysis and Planning
- Maintenance and Evaluation
Let’s dive into each of these stages and discuss how they work and how they apply to the development of a software project.
Stage 1: Analysis and Planning
Before you can develop a project or create a feature for it, you first need to know what you are going to build. What features should the project have? What features should it not have?
While many people see software development as just coding, there’s actually a lot more to it than typing out code. You’ll need to define the scope and boundaries of a project before you start coding. This is where you’ll figure out what you’re going to build and why.
During the analysis and planning phase, you’ll work with all project stakeholders – from executives to other developers and the customer – to ensure you develop relevant project specifications. You need to make sure the project not only meets customer expectations, but also the goals of your own business.
Stage 2: Design
So, you’ve got a plan of what you want to build. Now you have to ask yourself: how will we execute this plan? How are we going to build the features we have identified?
The next stage of SDLC is the design stage. This is where you will decide how features should be implemented while working with all stakeholders to ensure your plans align with their needs.
Working with others is essential at every stage of SDLC, but especially during the design stage. You may understand what you need to build, but if you don’t get input from all stakeholders, your design may not meet all requirements.
Stage 3: Development
After planning and designing, you’re ready to start development. This is where you’ll open up a terminal and a text editor to start working on the project. You’ll spend significant time building all the features agreed upon during earlier discussions.
Development is not just about writing code. At this stage, you’ll need to meet with other developers to assign work and discuss who is best suited to solve particular problems. It’s likely you’ll develop a process that helps you write code efficiently as a team.
Stage 4: Testing
You’ve done the heavy lifting and the features you needed to build are complete, but you’re not done yet. What if your code contains errors? Or what if your project does not work within a given edge case?
This is where the testing phase comes into play. You’ll need to identify what problems exist in your code and create solutions to those problems so the final product meets the specifications outlined in the analysis stage.
Stage 5: Deployment
The final product is ready. You’ve tested the code and made sure the final product meets all the original specifications. You’re now ready to start deploying the project.
This is where you will move the software you’ve developed from a testing to production environment. For instance, with a web application, you may move your code onto a live web server which hosts your website; with a game, you may publish your code on a game store.
Stage 6: Maintenance and Evaluation
While planning is an essential part of SDLC, you’ll find the needs of a project will change over time. Perhaps users ask for another feature or libraries need to be updated to ensure the product still works using the latest tools.
After publishing a project, you will be responsible for maintaining the product. Often, developers use Application Performance Monitoring tools to ensure their code is running effectively. If developers don’t maintain their applications, they could become unstable and cease meeting original project requirements. This would be harmful for business relations.
How SDLC is Applied
The Software Development Life Cycle can be applied to a software project in a number of ways. What you’ll find is that no two development teams are the same. Each will use their own models to implement SDLC while maintaining best practices which govern that model.
Let’s discuss three of the most popular SDLC models used by software teams.
The waterfall model is perhaps the most common implementation of SDLC. With this model, you move on to the next stage of the cycle once you complete your current phase. For example, you’ll start with analysis and once that is done, you’ll move on to the design phase.
This model is beneficial because evaluating progress is easy. However, it also has drawbacks. For example, if you need to backtrack because software requirements have changed, your final product may not meet all goals if you don’t have systems in place to go back and revise code that may no longer be relevant.
With the agile model, a cyclical approach to software development is taken. This means work is done in cycles, known as sprints, which usually last between two weeks to a month.
Agile supports iterative development. This means if you realize the product does not meet its initial specifications, you can easily go back to the design stage and implement necessary changes. These changes will then be made in the next sprint.
The incremental model is technically part of the waterfall model. It is a series of waterfall cycles. In this model, developers form groups and divide project requirements. Each group then implements the agreed upon SDLC.
This is a good model to use when you’re working on a large project with multiple requirements, as it can help you break down what is needed to advance the overall development of a project.
There are other models such as the big bang model, spiral model and the v-model. However, the three models we just discussed are the most common.
Professional development teams use the Software Development Life Cycle to ensure members do not lose track of tasks to be completed, like tests that need to be run or features that need to be built. The life cycle creates a standard approach to software development so every developer is aware of what is expected of them and when. This all ensures projects are delivered for clients on time and as expected.