AI security is crucial for mission-critical applications. The MITRE ATLAS framework helps identify and defend against AI attacks; however, practical tools are also essential in cloud-native environments. This panel brings together open source and enterprise security leaders to explore the operationalization of AI security using open source technologies aligned with the MITRE ATLAS. Key topics include an MITRE ATLAS overview, how tools such as Kubescape, Kubeflow, RHACS, Clair, and Kyverno support threat detection and prevention throughout the AI lifecycle, utilizing Kyverno for policy-as-code, Kubescape for ATLAS-aligned security, the alignment of MITRE ATLAS with other frameworks, and valuable lessons learned. This session fosters open dialogue and the sharing of insights among AI, security, and platform engineering communities to explore open-source solutions for ensuring trustworthy AI.