Navan is reinventing corporate travel and expense management for millions of users worldwide. As a Fullstack Software Engineer II on the Flights team, you will build and scale the mission-critical web applications and engine that power how users search, book, pay for, and expense flight itineraries in seconds. You will be reporting to the Senior Engineering Manager of Flights Platform.

The Flights domain sits at the core of Navan’s platform, combining intuitive, lightning-fast user interfaces with complex global distribution systems, high-throughput search queries, and real-time global transaction processing. We operate at scale, value engineering craftsmanship, and move fast. If you want to own end-to-end features—from pixel-perfect frontend experiences to robust high-availability backend services—and directly impact the travel experience of millions of users daily, this role is for you.

What You’ll Do

• Build End-to-End Features: Own feature delivery across the entire stack—designing modern, responsive user interfaces, defining slick API contracts, and implementing scalable backend business logic.
• Architect Frontend & Backend Systems: Develop modular, performant web applications using modern JavaScript/TypeScript frameworks while building low-latency REST/GraphQL APIs and microservices.
• Deliver Pixel-Perfect User Experiences: Collaborate closely with Product Managers and Product Designers to translate complex travel workflows into intuitive, accessible, and high-converting user interfaces.
• Ensure Fullstack Resiliency & Quality: Take full ownership of code quality by writing unit, integration, and end-to-end tests across the full stack, backed by robust frontend and backend telemetry, alerting, and observability.
• Optimize Performance: Drive web vitals, state management efficiency, and backend API latency optimizations to ensure users can book and pay within seconds.
• Elevate Developer Craftsmanship: Participate in design reviews, contribute to shared UI component libraries, and champion fullstack engineering best practices across the team.

What We’re Looking For

• Experience: 3–5 years of professional fullstack software engineering experience, with a track record of building and launching production-grade web applications.
• Core Fundamentals: Strong computer science foundations (data structures, algorithms, object-oriented design) and a deep understanding of browser runtime behavior, web architecture, and API design.
• Fullstack Mastery: Hands-on expertise writing clean, maintainable code on both sides of the stack—connecting rich client applications to scalable backend services.
• End-to-End Ownership: A builder mindset that takes pride in high-quality UX, solid backend logic, comprehensive test coverage, robust observability, and clear technical documentation.
• Cross-Functional Communication: Excellent, proactive communication skills to bridge technical trade-offs between design, product management, and platform engineering teams.
• Frontend Tech: Proficiency in modern JavaScript/TypeScript and frameworks like React, Next.js, or similar, alongside modern CSS/HTML and state management libraries.

• Backend & APIs: Experience with Java, Spring / Spring Boot, along with ORM technologies like Hibernate and relational database design.
• Cloud & Infrastructure: Hands-on experience deploying and managing applications on AWS within a microservices architecture.
• Domain Bonus: Prior experience building consumer-facing SaaS applications, checkout/payment flows, or travel technology integrations is a plus.