Top Fintech Software Engineer Jobs in Seattle, WA

Build and maintain scalable e-commerce and marketplace features across Node.js, React, MySQL, and MongoDB. Own complex features end to end, design backend services and APIs, integrate PunchOut procurement systems, improve platform security and reliability, conduct code reviews, and mentor engineers. The role requires strong full-stack JavaScript and TypeScript expertise, e-commerce domain experience, and the ability to work autonomously on high-volume transactional software.

Designs, builds, and scales backend services and integrations for payments, billing, identity, and partner connectivity. Sets technical vision and architecture for distributed systems, leads cross-team delivery, manages production rollouts, builds fault-tolerant services and data pipelines, and mentors engineers. The role partners with product, design, and engineering teams to deliver frequent, reliable improvements for Flex’s rent payment platform.

Build and scale backend data platforms and services for real-time loan origination and financial reporting. Lead quarterly delivery, guide engineers, define technical plans, collaborate with product and design partners, improve reliability and operational practices, monitor service metrics, participate in on-call support, uphold engineering quality standards, and mentor team members. The role requires developing highly available distributed systems and scalable data pipelines using technologies such as Python, Kotlin, AWS, MySQL, Kubernetes, Spark, and Airflow.

As a Senior Principal Engineer, you'll define and drive the technical strategy for customer experience platforms, lead architectural decisions, and mentor engineering teams to enhance customer and agent experiences.

Design, build, and operate scalable distributed systems for real-time restaurant payment and financial workflows. Responsibilities include architecting reliable services, protecting sensitive financial data, improving observability and production performance, debugging distributed systems, participating in on-call rotations, applying AI-assisted engineering tools, collaborating cross-functionally, and mentoring engineers.

Design, build, and operate foundational developer infrastructure across CI, build systems, deployment orchestration, and test platforms. Improve build speed, deployment safety, and test reliability while owning services end to end, including SLOs, observability, and on-call responsibilities. Partner with engineering teams to address platform pain points and lead cross-cutting technical projects through production.

Leads a 2–4 person engineering team while remaining hands-on in a TypeScript codebase. Owns delivery planning, performance management, career development, technical contributions, incident response, team health, quality, and compliance. Partners with Product, Design, and engineering teams to translate strategy into reliable software, manage risks and dependencies, remove blockers, and improve productivity through AI-enabled engineering practices.

Build and expand fintech and payment systems using Go, microservices, databases, and cloud technologies. Design production APIs and tooling, diagnose customer issues, manage full release lifecycles, document systems, and mentor engineers. Collaborate with product and business teams while guiding AI agents to produce maintainable, observable, testable code that meets engineering standards. Work independently in a high-availability environment and contribute to next-generation financial products.

Design and own secure, scalable wallet infrastructure for custody, key management, transaction signing, authorization, recovery, and multichain systems. Architect support for MPC, HSMs, secure enclaves, TEEs, smart contract wallets, account abstraction, and emerging cryptographic approaches. Define security boundaries, policy engines, secrets management, authentication, and programmable authorization while making foundational build-versus-buy decisions and guiding systems from first principles through production.

Build and scale Go backend services for agent quoting, configuration, and application submission. Design APIs and distributed systems, write unit and integration tests, resolve partner-specific issues, contribute to architecture, support production debugging, improve CI/CD automation, and use AI coding tools in daily engineering workflows. Collaborate with adjacent teams and mentor teammates through pairing and documentation.