When it comes to selecting a static application security testing (SAST) tool, businesses are faced with a crucial decision that can significantly impact their application security posture. With the market offering a range of traditional and modern SAST tools, understanding the differences between them is key to making an informed choice. In this article, we'll delve into the pros and cons of traditional and modern SAST tools, exploring their approaches, advantages, and limitations.

Traditional SAST tools, also known as "deep SAST," are designed to provide comprehensive scans and uncover a wide variety of results. These tools are ideal for safety-critical and high-value systems that release at infrequent intervals, where the best coverage possible is paramount. However, they come with drawbacks, including long scan times, high resource intensity, and a high rate of false positives, which require manual triage. This can be a challenge for devops teams practicing continuous delivery and releasing multiple times a day.

In contrast, modern SAST tools, or "fast SAST," prioritize developer experience and provide more focused results with fewer false positives. These tools are highly customizable, easier to integrate into CI pipelines, and minimize friction with development teams. However, they require a deeper technical understanding of security testing goals and may not provide the same level of coverage as traditional tools.

When implementing SAST in a continuous delivery environment, businesses can choose between supervisory scanning and CI scanning. Supervisory scanning provides comprehensive insight into potential vulnerabilities and coding errors, while CI scanning and PR scanning are designed to catch vulnerabilities early, preventing them from entering production. The choice between these approaches depends on the organization's priorities and goals.

In addition to selecting the right SAST tool, businesses must also consider whether to bundle it with other application security testing tools. Bundling can be beneficial for productivity, creating a more integrated and streamlined AppSec program. However, it's essential to evaluate technical requirements and ensure that the bundle meets the organization's needs.

To make an informed decision, businesses should ask themselves three key questions: Do we prioritize the best coverage possible or a killer developer experience? Do we care more about finding all potential issues or preventing issues from entering production? Must all our application security testing tools be best-of-breed or are some more important than others? By considering these questions and understanding the differences between traditional and modern SAST tools, organizations can choose the right tool for their unique needs and improve their application security posture.

Ultimately, selecting the right SAST tool is a critical decision that requires careful consideration of business needs, developer experience, and integration with CI/CD pipelines. By weighing the pros and cons of traditional and modern approaches, businesses can make an informed choice that supports their application security goals and priorities.