What Is SDLC (Software Development Life Cycle)?

The Software Development Life Cycle, or SDLC, is a process that helps development teams plan, design, build, test, and launch applications in an organized way.

SDLC guides teams through each step of software development, helping ensure the final product is high quality, reliable, and easy to maintain. It maps out the journey from an initial idea to a finished application.

In the past, SDLC mainly emphasized how well software worked and how quickly it could be delivered. As cybersecurity has become more important, a new approach called Secure SDLC (SSDLC) has emerged. SSDLC adds security best practices to every step of development.

Why SDLC Matters ?

Without a clear process, projects face problems, inconsistent results, and delays.

SDLC helps teams by providing structure and predictability. It makes sure requirements are clear, keeps development organized, and reduces the chance of problems at launch.

However, traditional SDLC often leaves security until the end, testing for vulnerabilities only right before release.

This gap pushed the organization toward DevSecOps and SSDLC, where the development, security, and operations teams work together.

Key Components of SDLC

• Planning: Define project target, resources, and timelines
• Requirement: Gather information about what the user or stakeholder needs
• Design: Develop system architecture, data structure, and user interface plans.
• Development: Write and compile code based on specifications
• Testing: Perform functional, performance, and security testing
• Deployment: Release the software to production
• Maintenance: Monitor, fix issues, and update the patch or package if needed

How SDLC Evolved into SSDLC

In traditional SDLC, the team conducts security testing late, often just before deployment.

This model can give you risk and increase cost when critical security issues are found late in the cycle. The Secure SDLC (SSDLC) improves this by integrating security testing tools like SAST, DAST, and SCA during the development phase.

With this new approach, security teams collaborate earlier with the developer team.

• Vulnerabilities are found before code reaches production.
• Compliance and threat modelling are becoming part of the process.

In short, SSDLC = SDLC + Continuous security

How DevOps and DevSecOps Fit into SDLC

DevOps enhances SDLC by integrating development through automation, collaboration, and continuous integration/delivery (CI/CD), accelerating release and improving software quality.

DevSecOps expands this further by embedding security best practices into each SDLC phase, making security a shared responsibility, and automating vulnerability checks for safer software.

Benefits of SDLC

• Ensure predictable and organized software development.
• Improves software quality and performance
• Help manage project risks and costs.
• Enable early detection and mitigation of issues.
• Supports continuous security integration with SSDLC and DevSecOps

Example in Practice

A SaaS company plans and develops a customer portal using the SDLC method. Initially, they apply SDLC to accelerate the speed of delivery. However, in the middle of development, the team experienced with security issues, then they adopt SSDLC by integrateing static code analysis (SAST) and dependency scanning (SCA) into their CI/CD pipeline.

The result: faster releases and fewer vulnerabilities in production.

Related Terms

• SSDLC (Secure Software Development Life Cycle)
• DevSecOps
• Static Application Security Testing (SAST)
• Software Composition Analysis (SCA)
• Dynamic Application Security Testing (DAST)