Staff Application Security Engineer

Overview Staff Application Security Engineer with deep expertise in Application Security, Identity & Access Management, and Confidential Computing to strengthen the security of Ledn's Bitcoin-backed loan platform. This is a hands-on engineering role focused on product security, infrastructure security, and customer trust. Ledn is a global financial services company for digital assets, offering lending, savings and trading products in over 150 countries. Our core values are integrity, ownership, progress, and empathy. We are a remote-first, globally distributed team. What You’ll Do 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. Remediate vulnerabilities and improve secure development practices with engineers. Own the roadmap for authentication and identity across customer and internal applications. Enhance Cognito-based identity architecture with stronger MFA solutions (WebAuthn, passkeys, hardware tokens). Collaborate with Product to align usability, compliance, and security in authentication flows. Define secure session management, device trust, and account recovery approaches. 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 and ensure compliance, auditability, and resilience of enclave workloads. 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 10 years minimum of proven experience in Application Security with 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, especially 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. Deep understanding of Linux internals; remediation of vulnerabilities identified in penetration tests. Strong communication and collaboration skills 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 with user-facing security features such as passwordless authentication, recovery flows, or device trust. Culture Fit Lead with integrity, adaptability, resilience, and comfort navigating ambiguity in a high-growth environment. Builder’s mindset—create, iterate, and scale information security practices. Collaborative and empathetic across functions and cultures; accountable with confidential information. Experience working in a remote environment. A Taste Of What We Provide Growth opportunities within Ledn, a leading digital asset company. Comprehensive rewards package and competitive PTO. Ownership in the company through equity. Remote work eligibility for up to 180 days (subject to restrictions). A purpose-driven career and a barrier-free work environment. No agencies or recruiters. We are an equal opportunity employer and welcome applicants from diverse backgrounds. #J-18808-Ljbffr