Software Development Life Cycle: An Ultimate Guide
We’ve never lived in a more competitive world. Today, it’s not enough just to have a web source. In order to achieve sustainable growth and success, businesses need to have a strong online presence. The tricky part is it’s not that easy to stand out from the crowd. With new web applications appearing at a mind-blowing speed, it’s highly important to build a product that appeals to the audience and can withstand the competition.
Here are just a few of the jaw-opening statistics you may want to know:
- New websites and applications appear every three seconds (imagine how many of them will be created by the time you finish reading this guide!);
- 71% of businesses across all industries have a web presence in 2023;
- Of the 1.13 billion websites that have been created by 2023, only 18% are active and maintained by the team.
Now, considering that the average cost of building a web soltion can range from $12,000 to $150,000, it’s clear that building one must be approached with a strong strategy in mind. That’s where the Software Development Life Cycle (SDLC) comes into play. In this guide, we’ll tell you all about SDLC, including its role, main stages, types of models used, and how to optimize it to lower development costs while delivering high-quality software that lives up to your customer’s expectations. Let’s start digging!
What Is Software Development Life Cycle and How Is It Different From System Development Life Cycle?
Before we begin, let’s first make a quick note of what SDLC is and how it is different from the system development life cycle.
In layman’s terms, the Software Development Life Cycle is a process that development teams use to bring a product from conception to life. It includes several phases and adheres to the software requirement specifications provided by stakeholders. Each phase of the STLC has a plan with a defined timeframe and established derivables, allowing teams to monitor progress and ensure software is meeting its goals.
On the other hand, system development is a broader term that covers both software and hardware components as well as organizational aspects. The term was first mentioned in 1960 in reference to the management process of large software projects on enterprise mainframes and has been used synonymously with the software development lifecycle ever since. But are they the same? Not quite, though the differences between them are rather subtle.
Here’s what makes them different:
- The system development concept covers both hardware and software components, as well as mobile and desktop apps. When it comes to software development, it only covers software components.
- Software development is limited to development planning, architecture, QA/testing, and deployment. System development, on the other hand, may also include change management and organizational updates required to increase the effectiveness of software development and marketing activities.
- The software development life cycle approach is often seen as a derivative of the system development approach.
Let’s explain the difference by taking a look at examples.
Example. Suppose you’re building a shipping label printer that’s controlled by custom software and a proprietary mobile application for it. When describing the development of a mobile app, the process that it undergoes would be called a software development life cycle, whereas the design of the printer itself would best fit the concept of a system development life cycle.
Many offer to change this approach and pay more attention to the difference between the project life cycle and the product development life cycle.
Example. Let’s go back to the printer again to explain the idea. In this case, when talking about the stages that a printer must go through (both hardware and software), we’ll use the term “product development life cycle”.
Say you outsource the development of a mobile application for your printer and software quality assurance services. For your vendor, this will be a separate project that will require careful planning according to the project life cycle, including the initiation, planning, execution, and closure phases.
We’ve got 22+ years of experience creating and managing different software products. Get in touch to discuss your project!
Benefits of SDLC
It’s hard to underestimate the importance of the systems development life cycle. You need to have a clear understanding of how SDLC works to develop a strong strategy to produce great outcomes. This is especially true if you outsource IT services. Knowing and understanding each development phase will add more trust to the relationship with a vendor and make it easier to set expectations and assess your progress.
Besides trust, there are a number of other important benefits of SDLC that make it important to embrace and implement in your software development projects. Here they are:
- Clear Objectives
The benefit of SDLC is that it gives a clear plan for each step, so there’s no confusion. The team knows exactly what they need to do in order to move from one phase to the next, and they have clearly defined deliverables to track their progress. This level of transparency positively impacts the development and operations of the project and eliminates resource wastage.
- Fast Delivery
A high level of transparency in the development process contributes to faster delivery of the final product. By diligently following all stages of software development one by one, the team can avoid common pitfalls and bottlenecks that often slow down projects and significantly speed up time-to-market. In addition, SDLC includes project management techniques that help teams meet deadlines (we’ll talk about this later in the SDLC Methodologies section).
- Cost Control
No less important is the fact that careful planning helps lower development costs. When the team and stakeholders agree on software development goals, they also estimate the cost of each phase of the project, focusing on the time, tools, and other resources needed to gain approval and move on to the next step. As a result, they can identify the areas where the most budget is being spent and make the necessary adjustments to improve cost efficiency.
- Risk Management
Another benefit of the SDLC is that it provides a structured approach to identify, assess, and mitigate risks throughout the development process. This allows development teams to resolve issues early, preventing costly errors or project failures later when a lot of time and effort has been invested in the project.
- Customer Satisfaction
Last but not least, a well-structured SDLC leads to higher customer satisfaction. During the first phase of the SDLC, development teams analyze user requirements and expectations to design and build a software product. Therefore, they have a higher chance that their solution will meet the needs of the end users, and there won’t be costly reworks in the post-development stage.
SDLC: Seven Stages, Their Challenges and Solutions
Now that we’ve explained how the software development lifecycle is different from the system lifecycle, and why it’s so important to arrange an SDLC process effectively, let’s delve into the stages of system development. In general, companies, including ours, distinguish seven common SDLC phases, each of which serves a unique purpose throughout the life cycle.
Stage #1. Planning and Feasibility Analysis
The first stage of the software development cycle is planning. At this stage, the software development team draws a plan (SDP), depicting in detail how the project will be brought to life from the idea to the realization. This phase is also known as the phase of brainstorming, where software developers, QA engineers, stakeholders, and other key people discuss project requirements and analyze all the aspects of a future software product. A lot of companies use the services of business analysts to back up the stages of SDLC.
The planning stage is successful when:
- Key stakeholders agree on software development objectives;
- All agents have a clear understanding of the project’s key value and proposition;
- The functionality chosen to reach/solve the problem is agreed on;
- Key tasks are documented;
- Key resources are planned, and responsibilities are distributed among team members;
- If applicable, dependencies and metrics are defined.
In the end, a business analyst or project manager creates documents, including all relevant information about the future product. If a BA doesn’t have a technical background, this job may be assigned to both a BA and a PM.
The key things to highlight in the documents are:
- Project description and its division into blocks;
- Resources that are required to complete each block;
- Estimated completion dates for each block;
- Expenses on hiring employees;
- Description of potential obstacles that may get in the way of the project;
- Solutions that can help overcome these obstacles;
- Any other critical moments that are relevant to the project;
- A project roadmap;
- Budget and roadmap with specific milestones.
When planning the software development process, teams conduct feasibility analysis to define the strengths and weaknesses of the project and estimate how much money, time, and resources are needed for the project’s success. To do this effectively, the entire SDLC is broken down into small components so that all key people involved in the development process can evaluate their tasks and set realistic goals.
There are five types of feasibility analysis:
- Technical feasibility — determines whether the team has enough tech and human resources to turn the client’s expectations into operational systems;
- Operational feasibility — stands for both how easy it will be to operate the product after its deployment and how the organization’s operational goals intertwine with the project in question;
- Economic feasibility — requires a cost/benefit assessment that includes the analysis of short, middle, and long-term gains or risks associated with the project;
- Legal feasibility — covers all legal aspects of the project (zoning, data collection and security, etc.) at any stage of its realization;
- Scheduling feasibility — determines the time required to complete the project and its compliance with the deadline previously agreed on by the client.
Disagreements over the results of the feasibility analysis are perhaps the biggest challenge. It’s easy to jump to the wrong conclusions, especially if you don’t have much experience conducting this kind of analysis. Therefore, it’s important to coordinate with a project manager, designers, developers, and QA testers to ensure you’re alerted of all red flags and don’t disregard them.
- Keep in touch with your project manager to find out what exactly will be checked at the feasibility analysis stage and how the outcomes can affect the entire project;
- Ask the team about how the feasibility analysis stage is going;
- Don’t hesitate to request more information from them when necessary;
- If there’s anything that worries you and/or you don’t agree with, be sure to tell the team about it straight away so they can make necessary adjustments early in development;
- If serious economic or legal issues arise, consider seeking outside professional help.
Tools and Techniques
The best tools and techniques to use at the planning stage are Kintone, Monday.com, GanttPRO, ZOHO projects, etc. However, no tool fits all scenarios. Therefore, it’s necessary to pay attention to a few factors, such as product- and project-based planning functionality, communication options, resource planning, access, analytics, and reporting features.
The most modern approach to feasibility analysis is to apply the PIECES framework that covers Performance, Information, Economics, Control, Efficiency, and Security issues. All these categories, at some point, are related to the seven stages of system development and should be thoroughly analyzed. If you want to avoid the most common hurdles that teams often overcome, make sure to lock in enough time for the planning stage.
Stage #2. Requirements
In the next stage, the development team collects requirements for the future product. It’s highly important to gather all relevant information as well as understand the needs and expectations of the end users. Ideally, you want to have a business analyst to back up this stage.
By and large, project requirements can be divided into the following groups:
- Business requirements. These are the requirements that are centered around why you need to develop a new application, what problems it helps to solve, and how it will help your business stand out among your competitors. It’s important to be very specific here. For example, you can write down that you expect your app to cope with high traffic loads (1k visitors per second), or you want your checkout process to take no more than two steps, and so on.
- Stakeholder requirements. A typical process of gathering project requirements can sometimes be tricky. People may have different ideas, and they need to be put together in one clear plan. That’s why it’s important to engage stakeholders in the process. Only when everyone agrees on software development objectives and functionalities can the project go ahead smoothly.
- Product requirements. By product requirements, we mean functional and non-functional requirements that refer to the app behavior and how good it is.
- Transition point. It is a list of people, tools, and other resources necessary to start the SDLC.
- Regulatory compliance. Aside from your own requirements, it’s crucial to check the standard regulations applicable to the software industry to ensure that your new software meets all legal and ethical standards.
The planning stage, without a doubt, is one of the most important ones. The better the project is planned, the lower the risk of costly fixes at later stages. This is especially true of companies that use the fixed-price business model or Waterfall methodology.
Unclear expectations and requirements are a recipe for failure. When goals and objectives are not clearly defined, the entire project becomes susceptible to disruptive changes right from the start. “Building a castle on sand” is a cliché saying, but it is exactly what happens when requirements are vague and the elicitation process is inadequately hard.
- Hold regular meetings with an agenda focused on the future product’s values, not just development milestones;
- Gather enough references that cover both “substance and style”;
- Be proactive and offer solutions that you think are best suited to the request based on your experience instead of blindly accepting the requirements imposed on you;
- Combine up-to-date project management tools with a product management vision.
Have an idea? We have the software development expertise to make it happen.
Stage #3. Software Design
Software design is a core aspect of the software development services cycle, which should be creative and clear. It involves the overall product design along with data structure and database design. In software design, there are three common strategies used:
- Structured design;
- Function-oriented design;
- Object-oriented design.
You are likely to love this phase, as it refers to visualizing the requirements and other data. You can take several core ideas and scenarios or find similar software applications that have been developed by someone else. There’s nothing wrong with taking a sneak peek at existing solutions, especially when you need to create visualization in a very short time.
Here are the key issues that you can add to the wireframe:
- UI or User Interface;
- Functional processes;
- Business processes;
- User journey.
Juggling priorities and restrictions is a background process of any quality software design. Having been in the software development outsourcing market for more than two decades, we have learned to effectively deal with this problem:
- Accept the fact that tradeoffs are inevitable;
- Be suspicious if specialists don’t ask about priorities — there are an infinite number of tasks, and it is impossible to handle them all at once;
- Don’t treat design as a deterministic process, as it can change organically or according to further requirements;
- Leave room and “air” for scalability and changes mentioned above;
- Don’t expect one person to cover everything once and for all, without room for growth or improvement — design is emergent and tends to evolve, absorbing various changes and processes.
Tools and Techniques
A bundle of tools and techniques used in software design is best described by one word — SOLID. Let’s unveil the five vital software design principles that it stands for:
- S — Single-responsibility — proclaims the “constituency of one” for every class, module, or function in the program;
- O — Open-closed — stands for extension-open but modification-closed principle for objects and entities;
- L — Liskov Substitution — implies that “every subclass or derived class should be substitutable for their base or parent class”;
- I — Interface Segregation — protects clients by claiming that users should never be forced to the interface they don’t actually use;
- D — Dependency Inversion — implies that both high- and low-level modules should depend on abstractions instead of low-level modules depending on high-level modules.
Stage #4. Development
This is the most important part of the software development process. A lot of brains work on coding to deliver a top-notch quality software product. As a rule, a company assigns a team of programmers to a project. All the tasks are then subdivided into sub-phases called Task Allocation so everyone knows what they need to do.
In general, there are tons of explanations of what a software development life cycle (SDLC) model means, so we won’t focus on it too much. Instead, we’ll break down its key components so you can better understand how it works:
- The choice of methodology. It can be Agile, DevOps, Scrum, or any other one.
- The choice of architecture. It’s the foundation of your future product.
- Coding. It’s a process of creating chunks of code from scratch based on the existing libraries.
- QA and testing. It comes hand-in-hand with the coding process.
Hiring the wrong people, too many people, or not enough people is the biggest risk in the development stage. Obviously, there are certain software development challenges that any development team inevitably faces at some point in time. However, if you choose the right team or dedicated developers from an IT outsourcing company to do the job — you’ll get past them with ease. To learn more about how to make software development outsourcing work for you, check this guide. Whether you’re just starting out or have already gone through several stages of SDLC, it will come in handy.
If you don’t know where to start, don’t hesitate to drop us a message. We’ll get back shortly!
Stage #5. Deployment, Implementation, Iteration
Typically, software contains a large number of programs that require careful implementation and step-by-step integration. During this stage, the project team checks how the software product behaves on various operating systems and devices. In case any bugs are found, testers fix them.
There are three major types of implementation:
- Fresh implementation — software replaces a manual system “from scratch”;
- Replacement implementation — the outdated software is replaced with new applications;
- Modified implementation — the old system is modified (separately), and this newer version replaces the outdated one.
A data integrity breach during the migration from one system to another can be one of the most damaging issues. Moreover, such breaches pose risks related to personal data security, turning what might seem like a simple challenge into a possible legal dilemma.
- Test systems’ interoperability or hire external QA experts to do it;
- Define which data can be safely transferred across systems and which should be synchronized via additional services, functionality or cannot be transferred at all;
- Pay extra attention to personal data security and check on the latest GDPR and similar regulations before you begin migration;
- Make a data integrity verification process continuous;
- If necessary, involve a third party as a moderator to ensure that the software meets data protection requirements.
Tools and Techniques
Depending on the current situation and goals of your business, you can choose the most suitable method of publishing your app. The most common options are:
- Recreate. A new version of the software is published after you terminate the current version.
- Rolling and ramped. A new version replaces the old one during a specific period of time.
- Blue and green. A new version is published alongside the old one. Traffic switches to the new release after some time.
- A/B testing. Users are divided into two groups, and each gets a new or old version to test.
- Shadow. The old version will exist until the moment it receives no traffic.
The next phases will comprise iteration and monitoring. During these phases, you’ll analyze the user’s behavior and get feedback. Most likely, you’ll also need to make some updates to the product to make it competitive and attractive.
Stage #6. Software Testing
After coding is finished, the software is passed to the testing department. Testers play a vital role in the quality of software and its performance. They test the product using various test cases to ensure it’s verified and debugged before the launch. Only when the QA team confirms that the software is error-free does the product go to the next stage.
Unrealistic testing environments and a lack of real, modern testing devices are the main hurdles on the way to efficient and productive software testing.
- Establish a good communication flow within the team — this will allow you to get immediate feedback and help refine your strategies;
- Employ extra brainstorming sessions to come up with as many possible real-world scenarios and combinations for testing as possible;
- Set priorities to make sure you test what needs to be tested first. Forget about milestones and pre-agreed activities for a moment and use a product