Software Development Life Cycle (SDLC): Step-by-Step Guide
Wondering what Software Development Life Cycle types are making waves in 2024? Give preference to those which will increase your chances of avoiding costly mistakes and delays in implementing various stages of development. So you can comprehend the features of the development cycles and pick the most effective methodologies for every project you run.
The primary goal of the SDLC is to generate high-quality software products that fully meet even the most nominal customer requirements. Regardless of the approach, any software development process consists of steps, including requirements gathering, design, coding, and so on. Compliance with all stages and pre-planned milestones allows product organizations to achieve impressive results and create a valuable product.
Today you can find an impressive array of offer security testing tools for the SDLC process. Most of them you can easily integrate into the life cycle of a product development depending on the terms and goals you are aiming to reach.
Ensure to utilize Software Development Life Cycle phases to bring a clear understanding of which team member will take on a specific task and the particular results of each employee. This is the only way to ensure that the finished product fully meets the customer’s expectations.
What is the Software Development Life Cycle?
Software Development Life Cycle is a structured process that merges the critical stages of software development to deliver a high-quality product. While covering the entire product life cycle from idea to operation, the SDLC approach is an opportunity to arrange a systematic and disciplined workflow, regardless of the size of the project and time frame.
The primary purpose of the software development life cycle is to manage each stage of development and support the product according to customer requirements on time and with maximum efficiency.
Once you have defined development milestones according to the intended SDLC, you should stick to the planned milestones until the delivery of the end product.
Here is a good use case when the lack of SDLC in the development process can lead to a total result:
Let’s say your team needs to develop software according to the client’s vision and requirements. If the process is left to chance, the project team may decide to independently determine the upcoming stages and determine which developers will implement any given function. Next, one engineer will prioritize the design, another will choose to write some of the code, and a third will roll up their sleeves to accomplish the documentation.
As a result, the project will be doomed to failure. The team cannot conduct parallel development without understanding and vision of the workflow. For this reason, the SDLC usage strategy is the only way to deliver a product that meets the customer’s expectations on time.
The software development life cycle example.
SDLC process
It is not difficult to understand popular life cycle models because it concerns the description of each task necessary to start the software development process and deliver the finished software version. The division of SDLC into specific steps reduces financial costs and improves overall system performance.
Monitoring is also essential to development as it covers all the life cycle phases. This approach provides proper control over the timing of tasks, budget, and compliance with the investor’s requirements.
Some developers believe that common life cycles of software are meant to be used exclusively by Agile or Waterfall process models. However, modern product organizations actively use other process models, including hybrid approaches with customized phases.
SDLC phases.
Software Development Life Cycle phases are based on a clearly defined methodology that defines the software development processes. In essence, the SDLC methodology concentrates on the critical stages of software development, including:
- Requirements check and analysis.
- Entire process planning.
- Software design development, including architectural design.
- Development and coding.
- Penetration testing and quality assurance.
- Deployment and implementation.
A few paragraphs below will take you deep into the life cycle mechanisms and bring each of these steps into focus. So you can get a crystal clear understanding of what SDLC validation models are.
Requirements and analysis
This is the first stage that precedes the start of the entire software development process. Here you must collect all the client’s requirements and clarify the expectations regarding the product being developed. Typically, this task is performed by a business analyst or project manager. Representatives of the software development company make an appointment with the customer and discuss the following:
- What exactly does the investor want to create?
- End user portrait.
- Development life cycle.
- Project risks.
- Code review frequency.
- What tasks should the software solution solve?
All data provided to investors at this stage must be specified in a Software Requirement Specification (SRS) file. Moreover, the SRS document should detail the technical specifications of the software, the acceptable code quality, the recommended security tools for the future product, the estimated cost estimate, and project implementation planning.
Deliverables of this stage include: a full-fledged SRS document detailing plans for project implementation.
Design and architecture
“What will the final product look like”? This is a question that fully reveals the essence of this SDLC stage. You need to turn the software specification into a clear design plan or the Design Specification.
All the data you collected in the SRS file in the previous phase should be used as qualitative input to create a well-structured software architecture.
Next, you need to approve the project direction to move on to the design phase, which includes all the critical things regarding the new product, namely:
- Features list.
- Necessary security measures.
- UI design.
- Architecture analysis.
- Infrastructure requirements.
In some cases, the creation of a preliminary design is fully justified. Thus, product organizations avoid the need to make radical changes after the development phase is completed. Also, this way, you can see if the design meets the customer’s expectations before pulling up the sleeves.
Deliverables of this stage include: DDS (Design Document Specification) document containing detailed information about time constraints, risk assessment, design modularity, and product robustness.
Informational architecture example.
Software development
Once the development and execution of DDS documents are completed, the development team receives the green light to start working on the code. This is one of the most critical and time-consuming development life cycle stages. Here it would help if you favored flexible methodologies to speed up the coding process without losing quality.
Deliverables of this stage include: the source code of a testable, fully working product, considering DDS and SRS requirements, and conducting basic testing of the product (code reviews and static code analysis).
Testing
The working version of the software that was created at the previous development life cycle step must go through extensive testing. Modern product organizations use various testing approaches to evaluate a promising product.
These testing methods include but are not limited to:
- Unit testing.
- Security testing.
- Acceptance testing.
- Code quality testing.
- Performance testing.
- Non-functional testing.
- Integration testing.
Most internal and external experts prefer to use automated tests to run tests on autopilot and not waste time manually doing the same task.
Let’s say a team of engineers has discovered a defect. In this case, developers run code quality testing, and the code goes back a step in the life cycle to create a flaw-free version. System testing is considered complete if the product demonstrates stable operation, meets the software requirements of the previous stage, and is free of bugs.
Deliverables of this stage include: thoroughly tested software ready for a production environment.
Deployment
Upon completion of the testing stage, the software is considered ready for production. In some cases, the nature of the project means that developers must create tutorial videos or user manuals before distributing the software to the general public.
As a rule, a deployment step can be carried out on autopilot, especially for large projects with the appropriate capacities and tools. Product organizations with a low level of maturity or software development companies in London engaged in development in highly regulated industries are forced to prefer manual approvals.
Remember that deployment doesn’t have to happen for all users simultaneously. As a rule, IT companies take a more rational approach; namely, they provide access to a small number of end users (up to 15%) and gradually distribute the product to the rest of the client base. In this way, you can mitigate potential issues missed during testing, reducing the impact on the UX.
Deliverables of this stage include: a thoroughly tested product ready for use by the end user.
Maintenance
Each set of software development involves periodic checks and updates based on feedback from end users. Here are some of the most commonly used actions within this stage:
- Bug fixing.
- Setting up continuous monitoring.
- Upgrading the app to the newer version.
- Adding new features to the software.
Once developers receive information about a bug or discover a product vulnerability, the software returns to the appropriate SDLC stage. The product can be returned to the development stage if programmers encounter severe defects.
Deliverables of this stage include a fully working product that continuously witnesses updates and improvements.
SDLC methodologies
The methodology’s main task is prioritizing software creation and achieving goals most efficiently. Below you will find the most effective software development steps and will be able to choose the best option that matches your team’s experience and the project’s scope.
Ideally, the life cycle model should be seasoned with regular updates and enhancements to deliver a high-quality software version. For this reason, updating and maintaining the proper level of development cycles requires special attention and efforts from stakeholders and several departments of the product organization.
The most effective SDLC models.
Scrum
The main feature of Scrum is that this methodology involves managing a project by dividing it into several stages. Next comes the repetition of the planning cycle, executing and evaluating each phase. The duration of Scrum phases, or as they are also called sprints, ranges from one to four weeks, with a check on the degree of completion of tasks after each sprint.
Advantages:
- Encourage creative approaches.
- Leads to better work.
- Involve low costs.
- More satisfied employees.
- adaptable and flexible.
- Improve customer satisfaction.
Disadvantages:
- It is not related to the project’s deadline.
- Requires the use of small teams.
- Challenge to scale.
- Requires experienced personnel.
- Requires extensive training.
- Hard to integrate with a classic project management.
Agile
The agile model resembles a series of continuous cycles suggesting gradual and minor changes to the previous release. Product creation evolves as new features are added and improvements are made within each deployment.
Testing is also a required Agile methodology step at the end of each sprint. In this way, the development team can be sure that potential exploits are not missed before the product gets into production.
Advantages:
- Focus on regular testing boosts cybersecurity.
- Emphasizes code quality from the start of development cycle.
- Meaningful feedback from end-users and stakeholders.
- Perfectly fits DevOps principles.
- Identifies and addresses issues in the early verification phase.
Disadvantages:
- Intense sprints create high pressure on a development team.
- Challenging to maintain documentation.
- For experienced and highly skilled crews, only.
Waterfall
Waterfall methodology is one of the most straightforward approaches used in the cycle of development. Each phase of the Waterfall model takes place sequentially and directly depends on the previous stage’s results.
Advantages:
- Helps bottle eliminates necks and data silos.
- No special skills or training are required (perfect for low-skill developers).
- Trusted methodology with a logical progression of steps.
- Provides a tangible output at the end of each stage.
Disadvantages:
- Changes can cost you a lot.
- Long build cycles.
- Far from perfect for projects with changing needs.
- No way to skip any step.
- Requires more flexibility and code revisions after each phase.
V-Shaped
Verification and Validation Model, which many people know as The V-shaped model, involves parallel execution of coding and testing by development teams. The ideal V-Model does not include a separate testing phase since each development section requires mandatory consistent quality control.
Advantages:
- A simple methodology.
- Perfect for small projects.
- Superior defect detection.
- An emphasis on software testing.
Disadvantages:
- No built-in maintenance phases.
- Later changes bring high costs.
Prototype
The prototype approach implies that the development team must create some working prototype of the finished product as part of the design phase. Product organizations favor this model to collect valuable feedback from investors and end users in advance.
The comments and wishes of users can have a significant impact on the creation of the final product. Moreover, requested changes from the customer will help the engineering team navigate and create an improved prototype version.
Advantages:
- Easily adjusts to changes.
- Discover missing features.
- Ensures an early proof of concept.
- Validates a genuine need for the product.
- Minimizes the number of defects.
Disadvantages:
- It comes at a cost for advanced apps and products.
- Requires greater time resources than other SDLC methodologies.
- It acts more as a life cycle setup (not an entire life cycle model).
Iterative incremental
The main task is that developers create the product’s initial version as soon as possible. Next, the command starts an iterative process and makes changes in small iterations. This approach is suitable for improving overall system performance and is often used in the software industry when building large applications.
Advantages:
- Managing the product and analyzing progress is more accessible by splitting a project into smaller chunks.
- Provides tangible output due to users’ and stakeholders’ early feedback.
- Quickly discovers defects in the Software Development Life Cycle.
- Regular risk and cost-benefit analysis ensures the product is secure by design.
- Easy handles small-to-medium changes.
Disadvantages:
- Spend resources too fast if left without due control.
- The model can be demanding for users and stakeholders (requires continuous feedback on each iteration).
- Requires a solid understanding of product requirements.
Big Bang
This model is a favorite development life cycle tool for small projects that do not burden themselves with detailed planning and structuring of each process. It is enough to provide the funding and other resources necessary to deliver software likely to meet the investor’s appetites.
Advantages:
- Despite the high-risk approach brings impressive profits with minimal investment and time costs.
- Minimal planning before starting development.
- An ideal solution for small development teams who prefer to work without process formalization.
- Complete freedom of action for IT engineers.
- Excellent methodology if you are developing inexpensive and simple products that do not involve interaction with the end user and making a lot of changes.
Disadvantages:
- Minimal planning can lead to many mistakes.
- Lack of testing phase upon completion of each stage.
- It cannot be used on complex projects.
Spiral
The Spiral Model is a complex methodology inherent in large projects and teams developing large-scale products. The approach is a hybrid model that mixes various development life cycle steps and combines them with sequential processes. As a result, developers can refine each phase of the spiral as the development process repeats each step.
Advantages:
- The approach allows developers to quickly fix bugs by returning to the previous step.
- The model includes an in-depth risk analysis for strict compliance with regulatory requirements.
- The methodology is an ideal solution for large-scale projects that develop software for a long time.
- Rapid adaptation of the software to the expectations and needs of users.
- Minimal risks of impacting the UX negatively.
Disadvantages:
- High cost due to a significant number of iterations.
- Requires hiring experienced developers capable of completing tasks to the end with high quality before moving on to the next stage.
- Not suitable for small projects with a limited budget and minimal requirements for the final product.
Benefits of Software Development Life Cycle
A well-structured life cycle model allows you to lay a solid foundation for any project related to traditional software development. Besides, the development team will prove higher productivity because each stage’s development speed and sequence will be determined in advance. This way, you can reduce the cost of delivering the product while the customer maximizes the ROI (return on investment).
Here are 7 key benefits of the software lifecycle for a well-handled software development process:
- Boost system performance by properly prioritizing upcoming tasks.
- Align product features with business goals.
- Uphold high code quality standards.
- Meet deadlines and keep projects within the assigned budget.
- Reduce the number of retroactive fixes that impact the UX.
- Keep bugs and vulnerabilities out of the development cycle.
- Stay away from conflicting or low-value tasks.
Benefits of a strong SDLC.
The life cycle model, properly applied, will help you ensure high-quality documentation and a high level of managerial control over the entire development process. This includes the security testing and deployment phase alike. More importantly, development teams can entirely focus on the upcoming stages with the true wisdom of what and why they perform to create high-quality software.
Despite the enormous benefits of the software development life cycle, this approach still has room for improvement and some pitfalls to keep in mind. For amateur teams, such a tool can become a severe obstacle instead of one that can clean up even the most complex projects.
Possible hardships with Software Development Life Cycle also arise due to inattention to the needs of customers and the definition of system requirements from the first day of the start of a project. Strict adherence to the detailed plan and attention to the client’s business needs is the only way to unleash SDLC’s benefits.
Software Development Life Cycle best practices
SDLC best practices example.
It is not challenging to implement a suitable SDCL model. The main thing is based on the project’s needs and the development team’s experience. Here are some fundamental guidelines to keep in mind when enforcing SDCL techniques for an upcoming project:
- Address security at an early stage. Ensure to implement security assurance activities from the early days of product development, regardless of the model. It will be better if conducting security assessments are planned before the design stage. The SDLC address security technique makes it possible to carry out threat modeling even at the initial stages of analysis.
- Standardize static code analysis. Take care to provide clear code quality testing recommendations to the team. Ensure developers do not deviate from the intended code review requirements to avoid slowing the process and causing other errors.
- Establish an iteration management system. Using a well-structured version control system for the product will allow the engineering team to keep all the code in one place. As a result, you can implement an additional layer of security and avoid costly failures in the later stages of a project.
- Be vigilant with project risks. A properly selected model for existing systems should consider risk analysis and use best practices to mitigate potential threats.
- Automate development life cycle tests. Automation of test models will significantly reduce time and resources, especially if the development process involves regular tests.
- Power the workflow with documentation. The documentation is nothing short of a treasure trove of information for quality control experts, developers, and analysts. The same goes for designers who rely on the design document specification. These files are the core of the SDLC. So ensure they are properly stored and accessible to all authorized team members.
- Upgrade team skills systematically. The organization of seminars and training in advanced coding methods, software deve tools, and integration testing techniques directly depends on successful brainstorming and improving the personal performance of product organization personnel.
Remember that your own experience may supplement the above recommendations depending on the project’s specifics and the team’s size. Limeup specialists mention that the software development lifecycle is a process that requires constant improvement and customization to keep pace with the changing environment and investor preferences.
Security in the Software Development Life Cycle
Example of Secure SDLC.
SDLC address security is the initial concept that was considered when creating the development life cycle to ensure the proper level of security within the testing stages. It is recommended to address security to:
- Develop more secure software from project to project.
- Detect system flaws early.
- Significantly reduce costs.
- Optimization of internal business risks for the organization.
It’s no secret that security is always critical to successful product implementation. Strive to create reliable software? Put the foundations of security in every project and control this aspect from stage to stage.
Final thoughts on Software Development Life Cycle
The model allows you to focus on various stages, including requirement analysis, planning phase, software design, development, testing, and deployment. More importantly, software development life cycles enable organizations to take a disciplined and systematic approach to building high-quality products that meet the needs of investors.
Wondering how to avoid project failure and achieve impressive rapport between team members? Methodology covering various software development services is the way to go.
There is nothing complicated in implementing a specific strategy because its choice will always depend on the individual parameters of the project. Analyze the business goals set by the customer, the experience of the development team, and the required code quality standards and coordinate these parameters with each stage of development.
Remember that regardless of the programming language or testing environment, each SDLC milestone must have a specific outcome, including a work product, document, diagram, etc. A definite result signals the developers that the previous phase is fully completed, and the team can proceed to the next steps.