Staff Application Security Engineer

OverviewJoin to apply for the Staff Application Security Engineer role at LEDN Ledn is a global financial services company built for digital assets, helping to improve the everyday lives of Bitcoin holders while building generational wealth for the future. We offer lending, savings and trading products to digital asset holders in over 150 countries. Our team is diverse and values integrity, progress, and empathy. ResponsibilitiesLead secure design and code reviews across engineering teams. Define and enforce secure coding practices for JavaScript/TypeScript services. Automate vulnerability detection (SAST, SCA, DAST) within CI/CD. Conduct threat modeling and risk assessments for new features. Remediate vulnerabilities and improve secure development practices in collaboration with engineers. Own the roadmap for authentication and identity across customer and internal applications. Enhance Cognito-based identity architecture with stronger MFA solutions (e.g., WebAuthn, passkeys, hardware tokens). Define secure approaches to session management, device trust, and account recovery. Design enclave-based architectures to isolate and protect sensitive workloads using AWS Nitro Enclaves; integrate with KMS and secure APIs; migrate high-value operations into enclave environments. Harden AWS services (Lambda, API Gateway, SQS, SNS) with least-privilege IAM and secure key management. Improve Kubernetes security posture (RBAC, pod security, image scanning, runtime monitoring) and deploy/operate a SIEM framework with detection rules and incident playbooks. Support compliance initiatives (SOC 2, ISO 27001) with security controls and documentation. Qualifications10 years minimum of proven experience in Application Security with a focus on web and cloud-native applications. Strong knowledge of JavaScript/TypeScript/Golang/Python and modern web vulnerabilities (OWASP Top 10, auth bypasses, business logic flaws). Expertise with AWS security best practices, particularly in serverless architectures. Hands-on experience with AWS Nitro Enclaves for confidential computing. Deep understanding of authentication and authorization standards (OAuth2, OIDC, WebAuthn, FIDO2). Practical experience with Cognito/Auth0 (MFA, custom flows, secure session handling). Background in SIEM design and log correlation across cloud and application layers. Familiarity with Kubernetes security (RBAC, pod security, admission controls, image scanning). Experience with Secure Code Review and understanding of software supply chain. Strong communication and collaboration skills to influence engineering and product teams. Nice To HavesFamiliarity with Bitcoin custody and key management practices. Knowledge of Infrastructure as Code security (Terraform, AWS CDK). Experience on user-facing security features such as passwordless authentication, recovery flows, or device trust. Culture FitLeadership mindset, adaptable and resilient in a high-growth, fast-paced environment. Builder mindset to create, iterate, and scale IS practices. Collaborative and empathetic cross-functional partner with integrity and accountability. Experience working in a remote environment. A Taste Of What We ProvideGrowth opportunities at Ledn, a leading digital asset company. Comprehensive total rewards package starting on day one and a competitive PTO policy. Ownership through shared equity; remote-friendly policy up to 180 days per year (restrictions apply). A purposeful career with barriers removed to do what you love. We are an equal opportunity employer and value diversity. For accommodation requests during recruitment, please email the Ledn team confidentially. #J-18808-Ljbffr