Staff Application Security Engineer

OverviewStaff Application Security Engineer role at LEDN. Ledn is a global financial services company built for digital assets, helping Bitcoin holders in over 150 countries. We seek a hands-on security engineer with deep expertise in Application Security, Identity & Access Management, and Confidential Computing to strengthen the security of our Bitcoin-backed loan platform. Security is fundamental to protecting our customers and business, and this role will drive tactical improvements and long-term strategy for securing applications and authentication systems. You will work across our JavaScript/TypeScript services, AWS serverless stack (Lambda, API Gateway, Cognito, SNS, SQS), MongoDB and Kubernetes microservices, and evolve the authentication layer toward modern, phishing-resistant approaches. You will also design and operate AWS Nitro Enclaves to protect critical data and cryptographic operations in isolated environments. This is a hands-on engineering role with direct impact on product security, infrastructure security, and customer trust. About 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 MFA solutions (e.g., 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. 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 into enclave environments and ensure compliance, auditability, and resilience. Additional Security Domains Harden AWS services 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 focusing 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 across 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 We look for a leader who thrives in startup/tech environments and embodies our values: act with integrity, own it, have a passion for progress, lead with empathy. The Ideal Candidate Will Be adaptable and resilient, comfortable navigating ambiguity in a high-growth environment. Have a builder's mindset to create, iterate, and scale information security practices. Be a collaborative partner, able to influence across functions with empathy and clarity. Demonstrate integrity and accountability in managing confidential information across diverse contexts. Have experience working in a remote environment. A Taste Of What We Provide Growth opportunities in a leading digital asset company. Comprehensive total rewards package starting on day one. Competitive PTO and ownership via shared equity. Remote work option for up to 180 days per year (subject to restrictions). A role with purpose and the ability to remove barriers to doing great work. We are an equal opportunity employer committed to diversity and inclusion. Reach out for accommodation requests; requests will be handled confidentially. Notes Ledn Working Environment: remote-first, globally distributed teams. Please note, due to high application volume, only qualified applicants will be contacted. Shortlisted candidates may be asked to submit a short video response and the review of publicly available social media activity relevant to the role. No agencies or recruiters. Senior/Staff Application Security Engineer (Bangkok based, relocation provided) #J-18808-Ljbffr