Sezzle - Principal Software Engineer - Identity & Access Management

Remote - Mexico$72k - $132k2h ago

Requirements

• 12+ years of professional software engineering experience, including significant backend experience. • 12+ years • Deployed significant changes to a production application in the past 30 days. • Deep, hands-on expertise in authentication and authorization systems: OAuth2, OpenID Connect, SAML, JWT and session-based auth, token lifecycle management, and modern authorization patterns (RBAC, ABAC, policy-as-code). • Deep, hands-on expertise in authentication and authorization systems • Experience designing, building, or operating an API gateway or auth proxy at scale: whether a commercial/open-source gateway (e.g., Kong, Envoy, AWS API Gateway, Traefik) or an in-house edge service. • Experience designing, building, or operating an API gateway or auth proxy at scale • Proven track record leading a large-scale service extraction or migration: decomposing a monolith or large legacy service into well-bounded services with zero or minimal customer impact. • Proven track record leading a large-scale service extraction or migration • Strong proficiency in Golang, with experience building and maintaining RESTful APIs. • Golang • RESTful APIs • Expertise with SQL-based RDBMS (MySQL, PostgreSQL) and experience optimizing schema and queries for performance at scale. • SQL-based RDBMS • Solid understanding of distributed systems design patterns (e.g., transactional outbox, event-driven architecture, queues) and the specific challenges of high-throughput, low-latency edge services. • distributed systems design patterns • Demonstrated ability to bring new ideas forward, influence decisions, and lead complex technical initiatives across many teams. • bring new ideas forward • Demonstrated AI-forward engineering: you actively use AI tooling (e.g., Claude Code, Codex, Cursor, or custom LLM integrations) in your development work today, have opinions grounded in practice about where it helps and where it doesn't, and help teammates adopt AI-assisted workflows. • Demonstrated AI-forward engineering • Bachelor’s degree in Computer Science or a similar technical field (required). • Experience with identity platforms and standards implementations (e.g., Keycloak, Auth0, Okta, Ory, or in-house IdPs), and familiarity with fine-grained authorization approaches (policy-as-code, relationship-based access control) as we centralize authorization over time. • identity platforms and standards implementations • fine-grained authorization approaches • Experience with service mesh and edge technologies (Envoy, Istio, mTLS, rate limiting, WAF integration). • service mesh and edge technologies • Familiarity with threat modeling, secure design review, and common auth attack vectors (token theft, replay, CSRF, session fixation, privilege escalation). • threat modeling, secure design review, and common auth attack vectors • Proficiency in observability tools (Prometheus, Grafana, Datadog, New Relic), especially for latency-sensitive edge services. • observability tools • Experience with AWS cloud infrastructure, mainly AWS Aurora RDS, both MySQL and Postgres. • AWS cloud infrastructure • Experience in fintech, payments, BNPL, or consumer lending - familiarity with financial compliance (PCI-DSS, SOC 2), credit decisioning, or transaction processing systems. • fintech • Experience with CI/CD pipelines and containerized microservices (Docker, Kubernetes). • CI/CD pipelines • containerized microservices • Track record of shipping commercial APIs and platform infrastructure in high-growth environments. • commercial APIs and platform infrastructure • Proven leadership in guiding technical direction, improving system reliability, and scaling engineering organizations. • You have relentlessly high standards - many people may think your standards are unreasonably high. You are continually raising the bar and driving those around you to deliver great results. You make sure that defects do not get sent down the line and that problems are fixed so they stay fixed. • You’re not bound by convention - your success—and much of the fun—lies in developing new ways to do things. • You’re not bound by convention • You need action - speed matters in business. Many decisions and actions are reversible and do not need extensive study. We value calculated risk-taking. • You need action • You earn trust - you listen attentively, speak candidly, and treat others respectfully. • You earn trust • You have backbone; disagree, then commit - you can respectfully challenge decisions when you disagree, even when doing so is uncomfortable or exhausting. You have conviction and are tenacious. You do not compromise for the sake of social cohesion. Once a decision is determined, you commit wholly. • You have backbone; disagree, then commit • You deliver results - you focus on the key inputs and deliver them with the right quality and in a timely fashion. Despite setbacks, you rise to the occasion and never settle. • You deliver results • Sezzle’s Technology Stack: • Languages: Golang, Typescript, Python • Languages: • Frontend: Typescript - React and React Native • Frontend: • Backend: Golang • Backend: • Database: MySQL, Postgres, Elasticsearch • Database: • DevOps & Cloud: AWS, Kubernetes • DevOps & Cloud: • Version Control: Git • Version Control: • CI/CD: • Testing: Developer and AI-driven, focus on automated end-to-end, integration, and unit tests • Testing: • Open Source: Sezzle is focused on using open source, and we build what we can before buying! • Open Source: • What Makes Working at Sezzle Awesome? • At Sezzle, we are more than just brilliant engineers, passionate data enthusiasts, out-of-the-box thinkers, and determined innovators; we are skilled musicians, yogis, cyclists, chefs, golfers, dog-lovers, and rock-climbers. We believe in surrounding ourselves with not only the best and the brightest individuals, but those that are unique and purpose-driven in all that they do. Our culture is not defined by a certain set of perks designed to give the illusion of the traditional startup culture, but rather, it is the visible example living in every employee that we hire. • #Li-remote #full-time

Responsibilities

• Own the technical vision and roadmap for Sezzle’s authentication and authorization platform, including a dedicated API auth gateway and supporting identity services. • Own the technical vision and roadmap • Architect, design, and build scalable, highly-available auth services and gateway components primarily in Golang, leveraging AWS, RDS (MySQL/Postgres), and modern distributed patterns. • Architect, design, and build • Golang • RDS (MySQL/Postgres) • Design and lead phased, zero-downtime migrations of auth traffic and functionality, with clear rollback and safety mechanisms at every step. • Design and lead phased, zero-downtime migrations • Establish and evolve authentication and authorization standards across the platform: OAuth2/OIDC flows, token strategy (JWT, opaque, refresh), service-to-service auth (mTLS, workload identity), and fine-grained authorization models (RBAC/ABAC/policy engines). • authentication and authorization standards • Drive consistency and scalability across a distributed microservices architecture while maintaining the performance, reliability, and latency budgets expected of an edge gateway. • distributed microservices architecture • Partner with Security and Compliance to ensure the new platform meets fintech-grade security and regulatory requirements, and champion secure-by-default patterns across engineering. • fintech-grade security and regulatory requirements • Establish and evolve engineering best practices for observability, security, and CI/CD across teams, with particular rigor on the auth-critical path. • engineering best practices • Participate in the on-call rotation for the services you own, and help lead incident response and postmortems on the auth-critical path. • Participate in the on-call rotation • Mentor engineers and champion a culture of learning, innovation, and operational excellence. • Collaborate cross-functionally to translate business goals into technical roadmaps and deliver results that matter. • translate business goals into technical roadmaps

Benefits

• This is a fully remote role. We believe the best engineers can do world-class work from anywhere, and we hire accordingly. You get principal-level scope and ownership at a growing fintech, competitive compensation, and no relocation or commute attached to it. Work from where you do your best work.