Have you ever been working on a big giant (Empire State size) project and have no clue how to start? This was the story of many IT teams developing software applications many years ago. But when the software development life cycle (SDLC) concept appeared, the way tech teams build software changed forever. With the SDLC framework, IT teams were able to define the steps involved in software development at each phase. Teams could transform big projects into more specific and doable projects, faster and at lower costs. With the pass of time, more features and new models have been added to this framework. Let’s review the basic notions of the software development life cycle stages and models in 2020.
What are the Stages of SDLC?
Imagine that you are in the middle of a jungle and to survive – besides food and water – you need to stay safe in a tent. You have only one ax and whatever the jungle provides for you to build that tent. And you have only a few hours before it starts raining. Suddenly you are magically given a set of steps to follow, with the materials you need to gather from the jungle. And thanks to this guide in less than 4 hours, you were able to build a strong and safe tent!
The magic guide of the jungle works similarly to SDLC on IT teams when building software applications. They follow specific steps that help them launch and maintain their software efficiently. There are 7 phases of SDLC, which divide the development process into assigned tasks, completed, measured, and improved by IT teams. Yet the steps can vary depending on which SDLC model is implemented.
These are the 7 stages of SDLC:
During this first phase, the project leaders define the project’s purpose and the desired result. In case the software application is for a customer, it happens the same. The project manager reunites with the customer to discuss the product, its purpose, and the results they want to achieve. The team gathers as much information about the product from the customer.
In the planning phase, leaders are evaluating the terms of the project. Including how much the project will cost and who will be part of that project. They also target specific goals during a time frame, and overall, they create the basic structure for the project.
This second phase is part of the planning. The SDLC starts with a requirement analysis phase in which the persons in charge of the project establishes the software requirements. They analyze the aspects that are necessary to achieve the final goal. Defining and establishing requirements determines what the application will do and the resources needed to build the project. For example, if a team wants to develop software to control a robot that cleans, then the physical robot would be a requirement in the process.
During this second phase besides establishing the requirements for the final product, each member of the team has to understand their roles and tasks.
3. Design and Prototype
Once phase 1 and 2 are understood and established, developers can start designing the software. The design phase is what defines the way a software application will work. During this phase, teams establish the programming languages, screen layouts, and relevant documentation they will be using. Some of the fundamental aspects developers cover during this phase are:
- Architecture: Teams define if they want a specific type of template or if they want to implement any type of industry practice.
- User Interface: Teams define the way users will be interacting with the platform. Developers must build user-friendly platforms to increase engagement. That’s why planning these steps is crucial for how well the platform will perform.
- Security: Developers must define how they will keep the application secure. This means they need to see how the passwords will be protected, and overall, create strategies to keep all of the app data safe.
- Programming: Define what type of programming languages will they be using as well as what methods will they implement if they face problems or need help.
Prototyping also makes part of this phase. A prototype is the basic idea of how the application looks and works. Prototypes are a way for customers to get a sneak peek of how their application looks like; they might even discover their original idea was horrible and change it during this phase.
4. Software Development
During this phase, developers start the development of the software. If they work in a small project, one developer takes over the coding tasks, while on large projects, it might be divided and operated by different developers. Before starting to code, teams need to have clear predefined coding guidelines to reassure the quality of the code. In this phase, developers start building the entire system and giving shape to the project.
Depending on each team’s model, the phase may be conducted in sprints (Agile) or a single block (Waterfall). The majority of times, teams spend most of their time during this phase to ensure that the application will work efficiently.
All the SDLC phases are important, but testing is where developers get nervous and hug each other crossing their fingers that their hard work pays off. Different types of testing occur during this phase, such as code quality, unit testing, integration testing, performance testing, and security testing.
During this phase, developers fix bugs or small errors that might appear during the tests. The application can’t be released with errors on it, that’s why testing has to be made with caution and as many times needed. The objective is for users to be highly satisfied with the new app, use it regularly, and invite other people to use it. There is also the option to automatize some tests to ensure that they are never skipped.
When the testing phase is finished, and there are no bugs or errors in the system, the deployment process starts. During this phase, the tech support team joins, providing user feedback. The team makes sure that the software is up-to-date, and it’s secure enough for users.
In big teams, this phase is usually invisible because it’s automated. But for startups or small organizations, this process needs to be done manually. It depends on the experience of the team members and the type of application they are building (some apps are more complex than others).
At this point in the SDLC cycle, the application is successfully finished and being used. Yet this last phase is still important because it’s where bugs or small errors appear. Users might face some malfunctions in the app, which is why developers need to be ready to fix them quickly. During this phase, the team can develop new upgrades with features to make the application even better.
SDLC Models and Methodologies
As mentioned previously, SDLC is a continuous process from start to finish of a software application. And even though there are determined steps, teams adopt different methodologies that have diverse approaches to build their applications. There is not one single model; there are many. The most popular SDLC models are Waterfall, V-Shaped, Iterative, Spiral, and Agile.
The waterfall model was the first one of the SDLC process. This model consists of dividing all the phases of the project, each phase with its own tasks and objectives. This model includes gradual execution of every stage completely, meaning that the output of one phase is the input of the next phase. If one phase is not completed, it’s not possible to move forward on the next one. Another characteristic of the Waterfall model is that it’s strictly documented and has predefined features expected to be developed in every phase.
The waterfall model looks like this:
This SDLC model is also known as the validation and verification model because it’s based on testing every stage before passing to the next one. This means every stage has a control process to make sure that the development works perfectly, and it’s possible to start with the next phase of the process.
The V-shaped model looks like this:
The iterative model is all about repetition. Instead of starting fully knowing all the requirements, developers implement a set of software requirements, test them, and improve them. So, a new version of the software is produced in every iteration. This happens again and again until the project is finished.
The iterative model looks like this:
The Spiral model combines architecture and prototyping by stages. This model allows products to be released and refined through each phase of the spiral. Also, it’s possible to build prototypes at each phase, making it possible to detect and manage risks. This is why this model is the perfect solution for big and expensive projects – before spending more money and time, developers and the team build an application that can detect future problems.
The spiral model looks like this:
The Agile SDLC methodology strongly emphasizes developer-client communication. After every development iteration, the customer can see the results and let the team know if they are satisfied. Therefore, work is done in regularly iterated cycles that are identified as sprints—projects under the Agile model last usually from two to four weeks. This is one of the most popular models for remote teams.
The Agile model looks like this:
Scaling your IT team?
No matter which SDLC model you choose and how perfectly you design your project, without the right team, success won’t be possible. It’s like having a room full of Fender guitars and hiring doctors instead of musicians to play (not that doctors can’t play, but you get the point). We know hiring talented developers might be one of the most frustrating things. But with the right tools and headhunting skills, it’s more than possible. How are we so sure about this? We’ve been doing it for the last decade. You just tell us what type of remote developer you are seeking for your team, and in less than two weeks, you’ll have a fresh new face working with you.