DevSecOps in practice: How to build security into the application lifecycle, rather than tacking it on at the end?

In the traditional software development model, the application life cycle resembled a relay race. Developers wrote code and then “threw it over the wall” to a team of testers. The testers, once their work was complete, would hand it over to administrators for deployment. Somewhere along the line, often just before a production launch, the security team would enter the scene. Its job was to find all the holes and vulnerabilities, which inevitably led to conflicts, delays and the perception of the security department as a “brake” that blocks innovation. In today’s dynamic DevOps world, where new software versions are deployed dozens or even hundreds of times a day, this model is not only inefficient – it’s simply impossible.

In response to this challenge, the DevSecOps philosophy was born. It’s a cultural, organizational and technological revolution that breaks down the walls between developers (Dev), operations (Ops) and security (Sec). Instead of “tacking” security on at the very end, DevSecOps builds it into every phase of the application lifecycle, even the earliest. Security ceases to be the sole responsibility of a single, isolated team, and becomes a shared responsibility of all participants in the process. It’s a fundamental shift that allows the development of more secure software at the pace that modern business demands.

What is DevSecOps and why is the traditional approach to application security failing in the DevOps world?

DevSecOps is an evolution of the DevOps philosophy that integrates security practices throughout the automated software development and delivery process (CI/CD pipeline). The acronym symbolizes the merging of three worlds: Development (creation), Security (security) and Operations (maintenance). The main idea is to make security an integral part of the process, rather than a separate, final phase.

The traditional approach, often called the “waterfall” model, fails in the DevOps world for a simple reason: it is too slow and reactive. In an environment where code is integrated and deployed continuously (Continuous Integration/Continuous Delivery), there is no time to perform several weeks of manual security testing before each deployment. Trying to impose old methods on a new, agile process leads to one of two scenarios: either security is completely ignored in the name of speed, or it becomes a bottleneck that nullifies all the benefits of DevOps.

DevSecOps solves this problem through automation and integration. Instead of manual testing on the back end, automated quality gates and security scanners are introduced directly into the CI/CD pipeline. As a result, security feedback is provided to developers almost immediately, right at the code writing stage, rather than weeks later, when it is much more costly to fix a bug.

What is the philosophy of “shift-left security” (shift-left security)?

“Shift-left” (Shift-left) is the central concept and main strategic goal of DevSecOps. The phrase refers to the visualization of the software lifecycle as a timeline, running from the left (planning, coding) to the right (deployment, maintenance). In the traditional model, most security-related activities were far to the “right.” The shift-left philosophy is to systematically move these activities as far “to the left” as possible, i.e. as early in the process as possible.

The earlier in the life cycle a security bug is found and fixed, the cheaper, faster and easier it is. A bug found by a developer in his development environment can be fixed in minutes. The same bug, found by a pentester just before a production deployment, requires much more work – you have to roll back changes, retest the entire application and delay deployment. And if the bug is found by a hacker in production, the cost of fixing it and remediating the consequences (such as data leakage) can be astronomical.

Moving security to the left in practice means providing developers with the tools and knowledge to write more secure code from the start. It means integrating security scanners into their development environments (IDEs) and code repositories, as well as automatic security tests that run every time code changes.

What role does static code safety analysis (SAST) play in the CI/CD pipeline?

SAST (Static Application Security Testing), or static application security analysis, is one of the fundamental techniques for “moving security to the left.” It is a method of testing “from the inside out,” which involves automatically analyzing an application’s source code, byte code or binary code in search of known vulnerability patterns without running the program itself.

SAST tools act as an extremely sophisticated, security-specialized “spell checker” for developers. They scan code, looking for bugs that can lead to popular vulnerabilities such as SQL Injection, Cross-Site Scripting (XSS), memory handling errors (buffer overflows) or improper use of cryptographic functions.

In the CI/CD pipeline, SAST scanning is most often integrated at two stages. First, in the code repository (e.g., GitLab, GitHub), where the scan can be run automatically with each new change proposal (pull request). Second, at the build stage (build), where the scanner analyzes all the application code before it is compiled. With this integration, the developer gets immediate feedback on potential bugs, can fix them right away and avoid introducing vulnerabilities into the main branch of the code.

Why is software composition analysis (SCA) essential for risk management in open-source libraries?

Today’s applications consist of 80-90% off-the-shelf components and open-source libraries. Developers no longer write functions from scratch to handle JSON or logging – they use proven, off-the-shelf solutions. This speeds things up tremendously, but creates a powerful new risk: vulnerabilities in dependencies. If the library our application uses contains a critical security vulnerability, our application automatically inherits that vulnerability.

SCA (Software Composition Analysis) is an automated process that aims to identify all open-source components used in a project and detect known vulnerabilities in them. SCA tools create a “list of components” (Software Bill of Materials, SBOM) of an application and then compare it to public vulnerability databases (CVEs).

Like SAST, SCA scanning is a key component of the CI/CD pipeline. Running at the build stage, it can automatically detect that a newly added (or existing) library contains a critical vulnerability. The pipeline can be configured to automatically stop the build process in such a case and alert the development team to update the vulnerable dependency to a more secure version. SCA is an absolute necessity in software supply chain risk management.

How to secure infrastructure as code (IaC) and avoid configuration errors in the cloud?

Modern cloud applications are deployed with their entire infrastructure – networks, databases, permission systems – described in code form (e.g., using Terraform, CloudFormation, Ansible). This approach, known as Infrastructure as Code (IaC), offers huge benefits in terms of automation and repeatability. At the same time, a bug in the IaC code can lead to the deployment of infrastructure with critical security vulnerabilities (e.g., publicly accessible S3 storage).

Securing IaC is another key element of the shift-left philosophy. Instead of looking for configuration errors on an already running production environment, the very code that defines that infrastructure should be analyzed and verified. IaC scanners are used for this purpose.

Integrated into the CI/CD pipeline, these tools automatically analyze Terraform or CloudFormation files before applying them. They compare the defined configuration against hundreds of security best practices and industry standards (e.g., CIS Benchmarks). If the scanner detects that the code is attempting to create a security group with an open RDP port to the entire world, it can automatically block the deployment and inform the developer that a fix is needed. This is a proactive method of fighting configuration errors that is much more effective than reactively looking for them in production.

How can nFlo help your organization transform to a DevSecOps model?

The transformation to DevSecOps is not just about implementing new tools, but more importantly a cultural and process change. At nFlo, we act as a partner in this transformation, providing not only the technology, but also the knowledge and experience necessary to tear down the walls between developers and security.

Our services begin with a DevSecOps audit and maturity assessment. We analyze your organization’s existing CI/CD processes and pipelines to identify the biggest gaps and opportunities for security integration. Based on this, we create a realistic and customized DevSecOps implementation roadmap that takes you step-by-step to a mature, secure software development lifecycle.

We specialize in designing, building and securing CI/CD pipelines. Our team of experts has hands-on experience in implementing and integrating key security tools – SAST, DAST, SCA, IaC scanners and container image scanners – with the most popular platforms, such as GitLab CI, Azure DevOps and Jenkins. Most importantly, we also support the human aspect of the transformation. We provide dedicated training for developer teams on secure coding, helping them understand the security perspective and giving them the tools to build more secure applications from the start.