You won't get far in the IT industry if you don't know about the Software Development Life Cycle (SDLC) methodology. It provides best practices and a tried-and-true structure to any software development project.

As such, it's important to know what are its benefits, its most important stages, and its most popular implementations. Fortunately for you, we're going to dive into each of these subjects as part of this article. Let's dig in.

• What is the SDLC? 🤔
• Benefits of the SDLC 👍
• SDLC Phases 🔃
  • Planning
  • Creating requirements
  • Design and architecture
  • Development
  • Testing
  • Deployment
  • Maintenance
• SDLC Models 📊
• Conclusion 🏁

What is the SDLC? 🤔

Before we delve into the specific details, it's important to know just what exactly the SDLC is. Imagine trying to drive a car without ever doing something like that before. You wouldn't even know that you had to get inside the car, start the engine, or press the pedals. But, if you knew the order of the operations that you had to do, things would be much easier.

This is what the SDLC strives to offer: a set of steps that you should take when trying to develop software. It splits the process into bite-sized pieces that specialists in that field can deliver. Everyone knows where they are on the road to the release of the software from team members, to managers or clients.

Benefits of the SDLC 👍

Based on the statements from the previous section, the SDLC offers lots of benefits:

• A plan that offers guidance for team members, no matter their specialty
• A roadmap for managers and clients to gauge the performance of the team
• Clear separation of responsibilities between designers, architects, developers, analysts, or testers.
• Improves communication between disciplines and team members
• Clear "definition of done" for its major steps

SDLC Phases 🔃

The SDLC is usually split into 7 phases. Sometimes, however, you'll find additional ones added at the beginning or end, depending on the focus of that company/team. We're covering the most common ones.

Planning

The SDLC brings a plan for the software development process and establishes this straight with the first phase. During this planning stage, you're creating the structure that will govern your work.

Here, executives and managers do all sorts of things, from assigning managers and product owners, to people like developers, testers, or analysts. They also make estimations regarding the overall cost while allocating resources for the scheduled work.

Creating requirements

You now have all the necessary human and material resources, as well as approved budgets. Now, it's time to create the requirements that will govern the product that you're making.

Here, the experts from the business side of things come together with the analysts from the team as well as the development and testing managers. They draft up requirements and specifications that must be met by the software.

Design and architecture

After having a set of requirements, the actual software must start taking shape. This begins with broad scale designs and architecture decisions.

In this stage, the system architects start making decisions with development managers about technologies, designs, and general guidelines for the actual programmers. They may do some prototypes or proof of concept work, just to validate important things before moving onto the next stage.

Development

We're almost in the middle of the SDLC but this is where the actual work begins for the software developers. Based on the agreed upon requirements and design documents, the programmers begin to create the application.

This is where the type of actual work may be different, due to methodologies like Waterfall, Agile, and others. We'll talk about them later in this article.

Testing

Of course, after all the development, there comes a time to actually verify that everything that's being created by the programmers is correct. As such, we enter the testing phase.

Here, quality assurance professionals start examining the software using various methodologies like black box, gray box, or white box testing. Defects found go back to the developers and the process repeats itself for a few times before the software meets the agreed upon quality benchmarks.

Deployment

Once the application meets the initial requirements and the quality levels, it is considered “complete”. As such, you can deploy it into production. Users get access to it and they can then decide if the software actually meets their desires.

Maintenance

You thought things were over at deployment? Think again. Especially nowadays, you need to maintain a product after its launch for a period of time.

Users will certainly find defects and more nefarious individuals will certainly test out the security of your software. As such, you need to issue updates and make changes to improve things after launch.

SDLC Models 📊

Of course, there are variations on the main steps of the software development life cycle from above, which put their own spin on things. You can find the most important details about the various SDLC details below. Rest assured that dedicated articles are coming in the near future.

• Waterfall: This is the traditional SDLC model. It strictly follows the main phases above, with completed work “pouring” into the next like a waterfall. While useful in its own way, the waterfall model responds very badly to changes along the way.

• Agile: Mostly regarded as the opposite of waterfall, the Agile model, created from the Agile Manifesto, emphasizes reacting to changes along the way. As such, you need to communicate with the client and change things quickly based on their new desires/requirements.

• V-Shaped: This is a variation of Waterfall that incorporates testing at every stage of the SDLC. In many ways it is superior because you don't wait until the ending stages to verify if you've actually created functional software that met requirements.

• Iterative: This is a variation of Agile that emphasizes releasing iterations of the software and then gathering feedback to make changes in the general approach.

• Big Bang: This model bypasses partially or completely the requirements stage and throws resources at the other phases, primarily design, development, and testing. This can be useful if everyone is on the same page about what needs to be created.

• Spiral: This model goes through each of the stages of the SDLC in short time frames. Basically, for every new feature, you gather a requirement for it, design and program the functionality, test, deploy, and maintain it. You then start the process again for the next feature.

Conclusion 🏁

The Software Development Life Cycle is an important notion to master, no matter your own role in the process. From managers, to developers, tester, or even end-users/clients, everyone needs to know what plan they are following.