Cybersecurity

Shift Left

Definition

In cybersecurity, "shift left" refers to the practice of moving security testing, evaluation, and practices earlier in the software development lifecycle (SDLC) – that is, to the "left" on a typical project timeline diagram. The goal is to find and fix security flaws as early as possible.

Why It Matters

The cost and effort to fix a security vulnerability increase exponentially the later it is found in the SDLC. Shifting left saves time and money and results in more secure software.

Contextual Example

Instead of waiting for a final penetration test right before release, a team that practices "shift left" would use static analysis security testing (SAST) tools that integrate directly into the developer's IDE, providing real-time feedback as they write code.

Common Misunderstandings

  • "Shift left" is the core philosophy behind DevSecOps and the Secure SDLC.
  • It's about making security an integral part of the development process, not a final gate at the end.

Related Terms

Last Updated: December 17, 2025