Staff Application Security Engineer

Overview Join 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 a suite of egalitarian lending, savings and trading products to digital asset holders in over 150 countries around the world. Our team is diverse and committed to democratizing access to the global economy through Ledn7s products and services. We are seeking a full-time Staff Application Security Engineer with deep expertise in Application Security, Identity & Access Management, and Confidential Computing to strengthen the security of our Bitcoin-backed loan platform. This is a hands-on engineering role with direct impact on product security, infrastructure security, and customer trust. The Role Application Security: Lead 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. Partner with engineers to remediate vulnerabilities and improve secure development practices. Authentication & Identity: Own the roadmap for authentication and identity across customer and internal applications. Enhance Cognito-based identity architecture with stronger, phishing-resistant MFA solutions (e.g., WebAuthn, passkeys, hardware tokens). Define secure session management, device trust, and account recovery. Collaborate with Product to balance usability, compliance and security in authentication flows. Confidential Computing (AWS Nitro Enclaves): Design enclave-based architectures to isolate and protect sensitive workloads. Integrate Nitro Enclaves with KMS and secure APIs. Migrate high-value operations (e.g., cryptographic and financial processes) into enclave environments. Ensure compliance, auditability, and resilience of enclave workloads. Additional Security Domains 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). Deploy and operate a SIEM framework; develop detection rules, dashboards, and incident playbooks. Support compliance initiatives (SOC 2, ISO 27001) with security controls and documentation. What You Bring To Ledn 10 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, able to influence engineering and product teams. Nice To Haves Familiarity 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 & The Ideal Candidate We value leadership, adaptability, resilience, and collaboration across functions and cultures with empathy and clarity. Remote-friendly and startup/tech environment experience is a plus. Benefits & Additional Information Comprehensive, best-in-class total rewards package; competitive PTO; and ownership in the company through equity. Remote work flexibility up to 180 days per year (subject to restrictions). Ledn is an equal opportunity employer; we value inclusivity and diversity. During the recruitment process, accommodation requests are addressed confidentially. Please note: due to high volume of applications, only qualified applicants will be contacted. Shortlisted candidates may be asked to submit a short video response, and we may review publicly available social media relevant to the role. No agencies or recruiters, please. #J-18808-Ljbffr