secure
sdlc

Secure SDLC (Secure Software Development Lifecycle) is a method for integrating security throughout the software development process – from requirements specification and design to development, testing, deployment, and maintenance. 

The method is based on principles such as Security by Design and Security by Default, where security is incorporated from the outset rather than being added later. 

The goal is to spot and deal with security risks early on, instead of fixing vulnerabilities late in the project. Secure SDLC lowers risk, costs, and compliance challenges. 

At Nesp.ONE we assist companies in understanding and implementing Secure SDLC in practice. 

Security by Design means that security is built into the architecture and design of systems from the outset. 

This entails, among other things: 

• Threat modeling in the design phase. 

• Risk assessment of architecture choices. 

• Secure system integration. 

• Incorporation of safety requirements into specifications. 

Security by Design is a fundamental principle of Secure SDLC and ensures that security becomes a structural part of the solution – not an afterthought. 

Security by Default means that systems are delivered with the most secure default settings enabled. 

Examples include: 

• Least privilege as standard. 

• Encryption enabled by default. 

• Logging and monitoring enabled. 

• Unnecessary services disabled. 

Security by Default reduces the risk of misconfigurations and supports both compliance and vendor responsibility. 

Cyber threats, compliance requirements (e.g., NIS2, Cyber Resilience Act, and ISO 27001), and increasing customer demands make secure software development a business-critical discipline. 

Secure SDLC helps companies to: 

• Reduce security vulnerabilities. 

• Comply with regulatory requirements. 

• Document safety efforts. 

• Improve quality and stability. 

• Protect the reputation of the business. 

By working systematically with Security by Design and Security by Default, companies can document risk-based security. 

At Nesp.ONE we help companies implement Secure SDLC in accordance with applicable regulatory requirements. 

Implementing Secure SDLC requires organizational buy-in, technical maturity, and clear processes. 

It's about: 

• Integrate security activities into existing development methods. 

• Operationalize Security by Design. 

• Introduce Security by Default principles. 

• Ensure documentation and governance. 

Nesp.ONE Danish companies on the implementation and maturation of Secure SDLC in both agile and DevOps environments – including risk assessment, process design, tool selection, and compliance adaptation. 

Yes, Secure SDLC can be integrated into Agile, DevOps, and other modern development methodologies without changing the fundamental way your organization works. 

This primarily requires: 

• Adjustment of governance and roles. 

• Introduction of security requirements in backlog. 

• Automated security testing (SAST, DAST, SCA). 

• Clear control points in the CI/CD pipeline. 

• Architecture and design reviews. 

At Nesp.ONE we help you integrate security naturally into existing workflows and tools. 

Secure SDLC is the overall method for integrating security throughout the development lifecycle. 

DevSecOps is a practice that operationalizes security in DevOps environments—often with a focus on automation, CI/CD, and continuous scanning. 

Secure SDLC sets the structural framework.
DevSecOps is a way to implement it in practice. 

Security by Design and Security by Default are principles on which both approaches are based. 

Typical activities include: 

• Threat modeling. 

• Secure architecture design. 

• Secure coding guidelines. 

• Code reviews. 

• SAST, DAST, and dependency scanning. 

• Penetration testing and vulnerability scanning. 

• Documentation and compliance control. 

Activities are tailored to the organization's risk profile, maturity, and regulatory requirements. 

The costs depend on the size, maturity, and existing processes of the organization. 

In practice, Secure SDLC is often an investment in process optimization rather than an isolated security expense. Many companies find that early identification of vulnerabilities reduces overall development costs. 

A mature Secure SDLC reduces technical debt and security-related incident costs. 

Ideally, from the start of the project – as part of architecture and design. 

However, Secure SDLC can be implemented gradually, for example by first introducing: 

• Security requirements in backlog. 

• Automated scanning in CI/CD. 

• Threat modeling in the design phase. 

• Baseline principles for Security by Default. 

A step-by-step approach makes implementation realistic and organizationally anchored.