Security Engineer

Overview Ledn is a global financial services company built for digital assets. We are seeking a full-time 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 customers and the business, and this role will drive both tactical improvements and long-term strategy for securing our applications and authentication systems. The Opportunity Work across our JavaScript/TypeScript services, AWS serverless stack (Lambda, API Gateway, Cognito, SNS, SQS), MongoDB and Kubernetes microservices, and take ownership of evolving our authentication layer toward modern, phishing-resistant approaches. Design and operate AWS Nitro Enclaves to protect critical data and cryptographic operations in isolated, verifiable environments. This is a hands-on engineering role with direct impact on product security, infrastructure security, and customer trust. Responsibilities 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. Own the roadmap for authentication and identity across customer and internal applications. Enhance Cognito-based identity architecture with stronger, phishing-resistant MFA solutions (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 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. 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. Qualifications 10 years minimum of proven experience in Application Security with 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). 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; ability to remediate vulnerabilities identified in penetration tests. Strong communication and collaboration skills 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 & The Ideal Candidate We seek a leader who thrives in startup/tech environments and embodies our values: act with integrity, own it, have a passion for progress, and lead with empathy. Have a passion for progress, adaptability, resilience, and comfort navigating ambiguity in a high-growth setting. Builder's mindset to create, iterate, and scale security practices; collaborative across functions and cultures. Integrity and accountability in managing confidential information across diverse contexts. Experience working in a remote environment. What We Provide Growth opportunities within Ledn, a leading digital asset company. Comprehensive total rewards package starting on day one. Competitive PTO; ownership in the company through equity. Remote work anywhere in the world for up to 180 days (subject to restrictions). A purpose-driven career with barrier-free work. Equal opportunity employer; commitment to inclusivity and diversity. You may reach out to the Ledn team for accommodation requests throughout all stages of the recruitment process. Requests will be addressed confidentially. Ledn Working Environment: remote-first, global team with members in North America, Latin America, South Africa and Europe. Please note, due to high volume of applications, only qualified applicants will be contacted. Shortlisted candidates may be asked to submit a short video and we may review public social media activity relevant to the role. No agencies or recruiters. We do not accept unsolicited agency resumes. #J-18808-Ljbffr