This article details LinkedIn's efforts to upgrade its Static Application Security Testing (SAST) capabilities. It covers the challenges faced with legacy systems, the design principles guiding the modernization, and the implementation of a new GitHub Actions-based workflow to enhance security without disrupting developer productivity.

GitHub Actions allows users to specify any executable on the $PATH as the shell for running commands, rather than being limited to predefined shell values. This flexibility enables various unconventional uses, such as executing C code directly or modifying the $PATH dynamically. However, this raises potential security concerns, as it allows for unexpected behaviors in the execution environment.