Agile SDLC: Benefits and implementation

The Agile methodology relies on short, targeted tasks and frequent status check-ins with decision-makers to accelerate software projects. Agile aligns stakeholders – whether they’re developers, project managers, or end users – every step of the way to avoid large iteration loops and enable development teams to adapt to feedback more easily.

Integrating the Agile methodology into the software development lifecycle (SDLC) splits development into iterative phases with continuous user feedback. Most organizations end up deploying an Agile SLDC so they can adapt to market changes with faster, more flexible development.

Communication between team members and quick decision-making are core principles of the Agile approach. Because there are many more engineers and operations personnel than there are security practitioners, leveraging the skills of developers can help to expedite security fixes within an Agile SDLC.

The security team member acts as a project champion to scale application security across development teams. Organizing the team in this way, along with implementing security tooling, integrates AppSec into the Agile SDLC, achieving a DevSecOps approach to software delivery.

An Agile SDLC combined with AppSec helps developers deliver more secure code because security measures are part of development instead of being considered later. Before exploring the benefits of Agile, it’s worth reviewing why software development is shifting from the Waterfall methodology to Agile development.

How the Waterfall methodology is used for development

Before Agile concepts gained popularity in the 2010’s, Waterfall was the traditional model development teams used. The Waterfall approach organizes development so that each phase uses the output of one process as the input to the next in predefined stages without overlap. The developers test the product after the requirements definition, analysis, design, and coding phases, providing a clear roadmap for what comes next throughout the entire process. The testing phase consists of debugging and discovering defects during the evaluation process.

The Waterfall methodology can be effective as long as the projects are short term and the requirements are clearly defined. More often than not, however, rapidly changing market dynamics or product requirements force organizations to move away from Waterfall to a method that can keep up with fast-shifting market changes. 

Benefits of switching to Agile development from Waterfall

The Waterfall approach efficiently moves the software development through design and coding, arriving rapidly at the testing phase. However, if product testing uncovers an error, the software version must loop all the way back to design to make corrections. These macro-iterations are time-consuming and can delay projects. In addition, when using the Waterfall approach the development team implements security features that were designed much earlier in the process by the security team, which can hinder the effectiveness of a secure SDLC.

An Agile SDLC fosters shift left testing, a core principle that integrates software testing practices (including security) as early in the development cycle as possible so that security vulnerabilities can be detected during coding.

In addition to testing sooner in development, there are numerous other benefits for development teams that switch to Agile.

Adding security to software development is easy and efficient

The primary benefit of implementing an Agile SDLC is to integrate development, operations, and security (DevSecOps) together, forming a secure SDLC (SSDLC) as well. Development and operation teams are often integrated into a DevOps approach, but it’s become essential to add in a security element during code creation.

An effective way to make security easy and efficient and achieve a holistic integration is to apply Agile DevSecOps practice at scale throughout multiple Agile SDLC phases. During each sprint, the team should incorporate security before reviewing with stakeholders, ensuring customers approve of the software segment with security already included.

Security champions integrated into the Agile SSDLC

To ensure that an Agile SDLC involves the voice of security, organizations can build a security champions program. Security champions are developers that represent the security team and bring security to every development conversation. One security resource can then scale to support a large number of developers when it comes to application security.

Threat modeling incorporated early in the SDLC

Threat modeling examines the design of system operations and how data flows across system boundaries to assess potential risks. It identifies all potential attack points and designs a solution to mitigate each vulnerability – however, threat modeling is often viewed as a time-consuming, complex practice that slows down the SDLC.

An Agile SDLC lends itself to threat modeling incorporation due to its iterative nature. Integrating threat modeling into each sprint step reduces the size and complexity of the analysis, lowering the burden on team members thinking about potential attack scenarios. Identifying these vulnerabilities during a sprint is also a key component of shift left security.

Challenges of Agile SDLC security

While Agile is an excellent fit for a SDLC in rapidly-changing environments, without comprehensive project direction it comes with some challenges regarding security. These are two major challenges:

1. The rapid pace of change of an Agile SDLC strains legacy technology and processes.

2. Many legacy security tools and processes were not designed to integrate throughout the SDLC.

How to implement an Agile SDLC

While there are certainly benefits to applying an Agile approach to software development, it is helpful to review the best practices for implementation.

The core principles of Agile include communication between team members and flexibility in the face of change, which often leads to quick decision-making. As a result, you may need to adapt the team's environment and shift your organization's approach to enable this development style and cadence. Quick decisions are critical, so team leads should hold frequent, short meetings to define who is doing what and by when. Meeting more frequently will also promote an open culture in which team members will feel comfortable reaching out to solve a problem instead of spinning their wheels trying to solve it alone.

Another Agile implementation tactic is to hold regular forums for decision-maker feedback. The software development schedule should dictate roughly when the team needs customers and sponsors to make decisions, so having regular meetings with all relevant decision-makers already on the calendar can expedite this process.

Finally, enable development teams to choose the most effective tools while employing continuous security measures. For example, Snyk enables development teams to find and fix potential security vulnerabilities without slowing down software delivery.

Agile SDLC FAQ

Visit our Secure Software Development Lifecycle page to learn more about the secure SDLC and how Snyk can help your company ensure security during agile SDLC.