Software Development Lifecycle (SDLC): Phases & Models

Building software without a plan is like assembling IKEA furniture without the manual. You’re bound to end up confused and lost, and maybe even throw your hands up in frustration.

That’s where the Software Development Life Cycle (SDLC) comes in. It’s the blueprint behind every polished app and slick website you can’t live without.

There are so many adaptations of the SLDC that it’s easy to wonder, “Where do I even start?“

Don’t worry—we’re breaking it all down. From idea to launch (and everything in between), here’s your clear, no-nonsense guide to the phases and models of SDLC.

The best part? You don’t need an expensive stack to manage them. You can do it all easily with ! 

Let’s get building.

What Is the Software Development Lifecycle?

In simple terms, it’s a structured approach that guides software engineers through planning, designing, building, testing, deploying, and maintaining software while avoiding possible software development challenges.

Why bother with SDLC?

Without the SLDC, projects easily spiral into missed deadlines, bloated budgets, and incomplete features (remember the data from BCG?). 

Here’s what a well-established process can do for software organizations:

• Clarity: Everyone knows what happens next
• Predictability: Timelines and costs are easier to estimate
• Quality: Testing and feedback are baked in at every step
• Risk reduction: Fewer surprises and mid-project meltdowns

When do teams adopt SDLC?

SDLC isn’t just for tech giants building billion-dollar apps. Teams adopt it when:

• The project is complex and has multiple moving parts
• Clear communication between developers, designers, and stakeholders is crucial
• Budgets, timelines, and deliverables can’t be left to guesswork
• Long-term maintenance and updates are expected

🔑 In short, if the project matters, SDLC matters.

The 7 Phases of The Software Development Lifecycle

Every great app, tool, or game you love has been through these seven steps (or something a lot like them). Let’s break down each phase:

1. Planning (Setting the stage for success)

This is where teams sit down and figure out why they’re building something and what they hope to get out of it. Software development goals, budget, timeline, and all other software requirement specifications are clarified here.

• Teams conduct feasibility studies to assess whether the project is technically, financially, and operationally viable
• Risk analysis helps identify potential obstacles that could derail the project, from resource shortages to market uncertainties
• Project scheduling lays out a clear timeline, defining milestones, deliverables, and responsibilities to keep development on track

This stage sets the foundation for everything that follows, ensuring the team has a shared understanding of the project scope and expectations before any code is written.

2. Requirements gathering and analysis (Understanding what users and stakeholders really need)

Time to talk to the people who’ll actually use the thing. What do they need? What problems are they trying to solve? Write it all down.

• Conduct stakeholder interviews to gather insights directly from end users, clients, and other key players. These conversations uncover real needs, pain points, and expectations
• Translate this information into detailed software requirement specifications that serve as a blueprint for development
• Create user stories to capture specific features or functions from the user’s point of view, helping developers understand how the software will be used in real-life scenarios

The purpose behind all these activities is to make sure the final product actually solves the right problems. After all, no one wants to spend months building a feature only to find out users don’t need it, don’t understand it, or can’t use it effectively.

3. Design (Translating requirements into a technical blueprint)

This is where ideas start taking shape. Teams sketch out wireframes to visualize how users will interact with the product. They create system architecture diagrams to map how different components will communicate behind the scenes. 

Design specification documents spell out everything from tech stacks to workflows, giving developers a clear playbook. Database schema design ensures data flows smoothly and securely. 

The goal? Turn requirements into a working blueprint that developers can confidently build from.

4. Development (Building the product, piece by piece)

The actual coding happens in the development phase. Developers write code, integrate components, and build the functionalities specified during the previous phases. Code editors then check and review it thoroughly. 

Features are often built in modular chunks to allow for easier testing, collaboration, and maintenance. Integration involves combining different components—like front-end interfaces and back-end logic—so they work seamlessly together. 

Version control systems (like Git) track changes, manage collaboration across teams, and prevent conflicts when multiple developers work on the same codebase. This phase is highly iterative, with teams building, testing, and refining in cycles to ensure everything functions as intended.

5. Testing (Making sure everything works—and works well)

Before release, software is rigorously tested to catch bugs, check code quality and security, confirm functionality, and ensure it performs under different conditions. Testing can be manual or automated.

Here are the multiple types and levels of testing teams perform:

Testing type	Purpose
Unit Testing	Verifies that individual components or functions work correctly in isolation
Integration Testing	Ensures different modules or services work together as expected
System Performance Testing	Checks how the software performs under various loads and stress conditions
User Acceptance Testing (UAT)	Confirms the software meets user requirements and is ready for release
Security System Testing	Identifies vulnerabilities and ensures data and system security

Together, these tests help teams release products with confidence.

6. Software deployment (Releasing the software to users)

Once testing is complete and the product is stable, it’s deployed for actual users. 

Production deployment involves pushing the final build to live environments, ensuring it’s stable, secure, and accessible to users. Depending on the strategy, this might be a full launch, a gradual rollout, or a limited beta to test real-world use. 

User training during this phase helps onboard customers or internal teams, providing documentation, tutorials, or hands-on sessions so they can use the software effectively. 

Release management oversees the entire launch process—from coordinating timelines to tracking issues post-release—ensuring everything goes smoothly and disruptions are minimized.

The goal here is to catch problems early and fix glitches fast so that the full rollout goes smoothly.

7. Maintenance and support (Keeping the software useful, safe, and up-to-date)

After launch, teams continue fixing bugs, improving features based on customer feedback, and adapting to new user needs or security threats. The maintenance phase ensures long-term usability and security.

Common SDLC Models and Methodologies

Choosing the right software development model is crucial to ensuring a project’s success. The model you choose will influence how your team works, the speed of delivery, and the flexibility of the project. 

Let’s go through some of the most popular SDLC methodologies.

Waterfall model

The Waterfall model is one of the oldest and most traditional software development methodologies. It’s a linear, sequential process where each phase is completed before moving onto the next. 

It’s called the ‘waterfall’ model because progress moves downward in clear, sequential steps—each phase begins only after the one before it is fully complete, much like water cascading from one level to the next.

Once a phase is over, you can’t go back. This model works well for projects with well-defined requirements that are unlikely to change during development.

Iterative model

The Iterative Model is all about building in steps, testing incrementally, and improving as you go. Instead of waiting to launch a fully finished product, you create a basic version first, then refine it through cycles of feedback and updates.

This SDLC model is perfect when requirements aren’t 100% clear upfront or when you know things will evolve.

Agile methodology

The Agile model focuses on iterative development, where the project is divided into smaller, manageable units called sprints. Each sprint delivers a functional piece of the software, and feedback is incorporated continuously. 

This model allows for flexibility and is great for projects where the requirements are expected to change frequently.

Spiral model

The Spiral model combines the Waterfall and Agile models and focuses on risk assessment. Development progresses in repeated cycles (or spirals), each addressing risks, design, and development. 

It’s particularly useful for large, complex projects that require ongoing evaluation.

V-Model

The V-Model is an extension of the Waterfall model but with a focus on testing. For every phase of development, there is a corresponding testing phase. This V-shaped model ensures that testing and quality assurance are integrated into the process right from the start.

SDLC vs. Agile: What’s the Difference?

At first glance, SDLC and Agile might seem like competitors, but they’re not. SDLC (Software Development Lifecycle) is the overall framework that defines the stages a software project goes through, from planning to maintenance. 

Agile, on the other hand, is a methodology (or an approach) that can be applied within the SDLC framework to manage how those stages are executed.

Think of SDLC as what happens during software development, and Agile as how teams choose to carry it out.

Here’s a summary table of comparison:

Aspect	SDLC	Agile
What it is	A framework outlining all stages of software development	A methodology for executing SDLC stages iteratively and flexibly
Purpose	Defines what needs to happen in a software project	Defines how it should happen
Scope	Covers the full lifecycle: planning to maintenance	Focuses on the process within each phase
Usage	Can be used with different methodologies (Agile, Waterfall, etc.)	One of the many approaches that can be applied within SDLC

In traditional SDLC models like Waterfall, phases are rigid and sequential—teams don’t move to the next stage until the current one is completed. This works for projects with fixed requirements but struggles with changing needs.

Agile flips this on its head. It encourages iteration and continuous feedback. Teams work in short sprints, releasing smaller chunks of the product and adjusting based on feedback. It’s ideal when requirements evolve or when early user input is valuable.

Both aren’t mutually exclusive—Agile is an SDLC model, just one of many ways to structure development.

Best Practices for Optimizing Your SDLC

A well-structured SDLC can make the difference between a smooth launch and a stalled project. Here’s how teams can fine-tune their software development process for better results:

Align cross-functional teams

When software developers, testers, designers, and stakeholders work in silos, miscommunication is inevitable. Ensuring everyone is on the same page from day one reduces costly delays and rework. 

Automate testing and deployment

Manual testing and deployments slow teams down and increase the risk of human error. Automating these tasks speeds up releases and improves consistency. 

Popular CI/CD tools like Jenkins, GitHub Actions, or Bitbucket Pipelines integrate well with your codebase to automate builds, tests, and deployments, so teams can focus more on developing features and less on repetitive tasks.

Track KPIs across each phase

Measuring what matters ensures projects stay on course. Tracking key performance indicators (KPIs) like defect rates, sprint velocity, and deployment frequency helps teams identify bottlenecks early. 

The KPI Tracking Template makes it simple to monitor these critical metrics in real time. It offers built-in, auto-updating dashboards that visualize progress and help you spot areas that need attention, through Custom Statuses such as Off Track, At Risk, and On Track.

Use project management and documentation tools

Centralized documentation and project tracking keep everyone aligned, especially in complex projects. Tools like Docs, Notion, or Confluence allow teams to document requirements, share user stories, and maintain knowledge bases that everyone can access. 

Coupled with task management, teams can ensure decisions, updates, and processes are documented and accessible when needed.

Now, let’s take a closer look at how to make the most of project management and documentation tools to optimize your SDLC process.

Did you know that AI can boost productivity by up to 40%? Pretty impressive, right? 

Smarter project management with

Well, brings that power into your SDLC process— from planning to deployment. 

Think, write, and build faster with AI

’s AI-powered software project management makes managing your SDLC feel effortless. At the heart of it all is Brain, your intelligent project co-pilot that brings automation, insight, and clarity to complex workflows.

During the planning and requirements gathering stages, Brain helps teams: 

• Generate project briefs
• Auto-summarize meeting notes, and 
• Create user stories directly from conversations or task threads

As teams move into design and development, Brain can:

• Write technical documentation
• Suggest process improvements, and 
• Break down large epics into structured, actionable tasks

For QA and testing, you can automate task assignments and tracks test cases using Custom Statuses and Automations—while Brain assists in writing bug reports, summarizing sprint outcomes, or interpreting logs and user feedback. 

Here’s what else ’s software project management suite has in store for you:

So, instead of wasting time on mundane project management details, your team can focus on what they do best: coding and delivering awesome products.

Stay on track with Sprints

For teams following the Agile methodology, the Sprints feature is a game-changer. Break your project into smaller, manageable pieces and plan fully customizable sprints to optimize delivery timelines. 

The best part? You can easily see what’s coming up, what’s completed, and where the development team might need to pivot. Sprint automations help refine your process, making repetitive tasks a thing of the past. 

With sprint points, you can easily estimate effort and align the team to focus on what matters most. Plus, you can manage timelines, code reviews, and iterations in one platform. Built-in graphs, such as burnup, burndown, cumulative flow, and velocity charts, make it easier to track progress and adjust strategies.

Get started quickly with ready-made templates

Getting started with is a breeze, thanks to its ready-to-use templates. Instead of setting up everything from scratch, you can start with a template built specifically for software development. 

For example, the Software Development Template has pre-built structures for recording tasks, setting milestones, and establishing deadlines so that you can jump right into planning.

This template covers all stages and helps you manage multiple portfolios and programs. 

Track progress across multiple sprints simultaneously, with 30+ statuses including in development, in review, and ready for deployment. Organize tasks using Custom Fields like MoSCoW, Quarter, and Squad. 

Choose from views like Board, Whiteboard, List, and Doc to fit your needs, while reducing system outages and staying on top of deadlines—all in one place.

is undoubtedly a great choice, but other continuous deployment tools can help you manage the process of developing high-quality software. Let’s check out a couple of them.

Jenkins: The automator

Jenkins is your automation ally for continuous integration (CI). It is a robot that works around the clock to make sure your builds, tests, and deployments happen automatically. 

Every time you push code, Jenkins acts as a QA testing tool, triggering automated tasks and running tests like JUnit and Selenium, catching bugs early before they become a headache. It integrates perfectly with version control systems like Git and has a plugin for just about anything. 

CircleCI: Fast, flexible, and cloud-ready

CircleCI is a high-speed, cloud-friendly CI/CD tool. It’s perfect for working with containers or cloud services like AWS or Google Cloud. 

One of its best features is native Docker support, which means you can test your code in isolated environments to ensure it runs perfectly everywhere. CircleCI takes care of everything, from running tests to deploying your app, while you focus on development. 

Optimize Your SDLC Process with

Managing the Software Development Lifecycle (SDLC) can feel daunting, but with the right tools, it becomes a well-defined path to success. Without a solid process, projects risk delays, scope creep, and missed deadlines. 

That’s where steps in!

With ’s comprehensive features, such as task management, sprints, templates, and automated workflows, your production environment becomes more efficient and predictable. From planning to deployment, helps you stay on top of every phase with ease and clarity.

Try today for free!

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