Security Engineer

Overview Security Engineers, Ledn is a global financial services company built for digital assets. Ledn helps to improve the everyday lives of Bitcoin holders while building generational wealth for the future. We offer lending, savings and trading products to digital asset holders in over 150 countries. Our team is diverse and committed to making a difference in the lives and futures of our clients. Ledn values integrity, accountability, progress, and empathy, and aims to change the world for the better through its products and services. 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 customers and the business, and this role will drive tactical improvements and the long-term security strategy for 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. This role also involves designing and operating 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 MFA solutions (WebAuthn, passkeys, hardware tokens). Collaborate with Product to balance usability, compliance, and security in authentication flows. Define secure approaches to session management, device trust, and account recovery. Design enclave-based architectures to isolate and protect sensitive workloads and integrate Nitro Enclaves with KMS and secure APIs. Migrate high-value operations into enclave environments and ensure compliance, auditability, and resilience. 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 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 practices, especially in serverless architectures. Hands-on experience with AWS Nitro Enclaves for confidential computing. Deep understanding of authentication/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. 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 are looking for more than operational excellence—someone who thrives in a startup or tech environment and embodies our values. The Ideal Candidate Will Be adaptable and resilient, comfortable navigating ambiguity in a high-growth, fast-paced environment. Have a builder's mindset to create, iterate, and scale security practices. Be a collaborative partner who can 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 at one of the world's leading digital asset companies. Comprehensive total rewards package starting on day one and competitive PTO. Employee ownership through equity; remote work up to 180 days globally (restrictions may apply). A purposeful career and a work environment that removes barriers so you can do your best. Equal opportunity employer; we value inclusivity and diversity. Equal Opportunity and Recruitment Notes You may reach out to the Ledn team for accommodation requests throughout all stages of the recruitment process. Requests will be addressed confidentially. Only qualified applicants will be contacted due to high volume. Shortlisted candidates may be asked to submit a short video response 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. Job Details Seniority level: Mid-Senior level Employment type: Full-time Job function: Information Technology Industries: Retail J-18808-Ljbffr

Location: Feira de Santana, Bahia, BR

Posted Date: 10/13/2025