Role Overview
The Principal Software Engineer for Identity & Access Management at Sezzle is a senior backend role responsible for leading the evolution of authentication and authorization platforms across a fully remote environment based in Colombia. This position is ideally suited for an experienced technical leader with a strong background in distributed systems who enjoys owning architecture, mentoring peers, and driving zero-downtime migrations.
Key Responsibilities
Own the technical vision and roadmap for Sezzle's authentication and authorization platform, including a dedicated API auth gateway and supporting identity services.
Architect, design, and build scalable, highly available auth services and gateway components primarily in Golang, leveraging AWS and relational databases.
Design and lead phased, zero-downtime migrations of auth traffic and functionality with clear rollback and safety mechanisms.
Establish and evolve authentication and authorization standards across the platform, covering OAuth2/OIDC flows, token strategies, service-to-service auth, and fine-grained authorization models.
Drive consistency and scalability across a distributed microservices architecture while maintaining strict performance and latency budgets at the edge.
Partner with Security and Compliance to ensure the platform meets fintech-grade regulatory requirements and champion secure-by-default patterns.
Participate in the on-call rotation for owned services and help lead incident response and postmortems.
Mentor engineers, foster operational excellence, and collaborate cross-functionally to translate business goals into technical roadmaps.
Requirements
12+ years of professional software engineering experience, including significant backend experience and deployed changes to production recently.
Deep, hands-on expertise in authentication and authorization systems such as OAuth2, OpenID Connect, SAML, JWT, session-based auth, and policy-as-code models.
Experience designing, building, or operating an API gateway or auth proxy at scale.
Proven track record leading a large-scale service extraction or migration from a legacy architecture to well-bounded services.
Strong proficiency in Golang with experience building and maintaining RESTful APIs.
Expertise with SQL-based relational database management systems like MySQL and PostgreSQL.
Solid understanding of distributed systems design patterns and high-throughput, low-latency edge services.
Demonstrated AI-forward engineering experience utilizing AI tooling actively in development workflows.
Bachelor’s degree in Computer Science or a similar technical field.
Nice to Have
Experience with identity platforms and standards implementations such as Keycloak, Auth0, Okta, Ory, or custom internal IdPs.
Familiarity with service mesh and edge technologies including Envoy, Istio, mTLS, rate limiting, and WAF integration.
Knowledge of threat modeling, secure design reviews, and common authentication attack vectors.
Proficiency in observability tools like Prometheus, Grafana, Datadog, or New Relic for latency-sensitive services.
Background in fintech, payments, buy now pay later models, or consumer lending alongside compliance frameworks like PCI-DSS and SOC 2.
Experience with CI/CD pipelines, Docker, and Kubernetes.
Skills and Tools
Languages: Golang, TypeScript, Python
Cloud & Infrastructure: AWS, AWS Aurora RDS (MySQL and PostgreSQL), Kubernetes, Docker
Security & Auth: OAuth2, OpenID Connect, SAML, JWT, RBAC, ABAC, API Gateways
Practices: AI-assisted development, distributed systems architecture, zero-downtime migrations
Salary and Benefits
Compensation range of $6,000 to $11,000 per month in gross USD, negotiable based on location and experience level.
Fully remote working arrangement with no commute or relocation requirements.
About the Company
Sezzle is a fintech company on a mission to financially empower the next generation through interest-free installment plans and innovative shopping experiences. By blending cutting-edge technology with consumer-centric solutions, the company drives impact for merchant sales while building a dynamic, purpose-driven team.
How to Apply
Interested candidates should visit the official company careers page to apply for this position.
