Building secure software development lifecycle (SSDLC) is crucial for creating resilient digital experiences. The SSDLC is a holistic approach that embeds security into every phase of software development, from ideation to deployment. It's guided by principles such as least privilege, data protection, regular audits, and secure coding practices. Secure software development best practices include early integration, continuous testing, education and training, collaboration and communication, automating tasks, and empowering developers to build security into their software from the get-go. The challenges of secure software development include resource strain, complex regulations, cultural resistance, false positives, and balancing speed and security. By equipping your team with the right tools, knowledge, and culture, you can turn these challenges into opportunities for growth and excellence. New Relic's interactive application security testing (IAST) is an integrated, continuous, and intelligent approach to security that complements secure software development practices.