Security Engineer

Overview Join to apply for the 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. Ledn offers a suite of egalitarian lending, savings and trading products to digital asset holders in over 150 countries. Our team is diverse, with a shared conviction that digital assets can democratize access to the global economy and Ledn’s products and services can play a critical role. Our core values guide us: act with integrity always, own it, have a passion for progress, and lead with empathy. We are building, innovating and revolutionizing financial services. The Opportunity 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 our customers and business, and this role will drive both tactical improvements and long-term strategy for securing our 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 take ownership of evolving our authentication layer toward modern, phishing-resistant approaches. You will 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 Application Security: lead secure design and code reviews; 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; 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 (WebAuthn, passkeys, hardware tokens); collaborate with Product to align usability, compliance, and security; 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 Enclaves with KMS and secure APIs; migrate high-value operations into enclave environments; 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 with detection rules, dashboards, and incident playbooks; support compliance initiatives (SOC 2, ISO 27001). What You Bring To Ledn 10+ years 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 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’re looking for more than operational excellence — we want a leader who thrives in a startup or tech environment and embodies our values. The Ideal Candidate Will Have a passion for progress by being adaptable and resilient, and comfortable navigating ambiguity in a high-growth, fast-paced environment. Have a builder’s mindset, eager to create, iterate, and scale security practices. Be a collaborative partner, able to influence across functions and cultures with empathy and clarity. Demonstrate integrity and accountability, especially in managing confidential information across legal and cultural contexts. Have worked in a remote environment before. What We Provide Growth opportunities and a comprehensive rewards package starting on day one. Competitive PTO and ownership in the company via equity; remote work flexibility up to 180 days per year (subject to restrictions). A purpose-driven career with a focus on removing barriers to doing great work. Ledn is an equal opportunity employer — we value inclusivity and diversity. Accommodations requests throughout all stages of recruitment are welcome and will be addressed confidentially. Ledn Working Environment: Our team is global and remote-first, with members across North America, Latin America, South Africa and Europe. Please note, due to high application volume, only qualified applicants will be contacted. Shortlisted candidates may be asked to submit a short video and we may review publicly available social media activity relevant to the role. No agencies or recruiters please. We do not accept unsolicited agency resumes and are not responsible for fees related to them. Additional Details Seniority level: Mid-Senior level Employment type: Full-time Job function: Information Technology Industries: Retail #J-18808-Ljbffr