Top Fintech Software Engineer Jobs in Seattle, WA

Lead two Payments engineering teams through platform modernization, including decoupling payment capabilities from business logic, improving observability, performance, reliability, and operational health. Manage engineering managers and individual contributors, guide technical direction with senior engineers, own third-party payment integrations, and partner with Product and Commercial on payment capabilities and priorities. Drive cross-team initiatives, develop talent, and balance product delivery with foundational architecture investments.

Own and lead the technical direction of a major codebase section while designing, building, testing, documenting, and maintaining secure, scalable API-based decisioning products. Partner with product, engineering, and security teams on agile delivery, troubleshoot production issues, meet SLA requirements, and participate in an on-call rotation.

Build and scale consumer-facing mobile and web applications and backend services. Own features end-to-end across frontend and backend, optimize databases and queries, integrate third-party APIs, implement algorithms for risk and transaction evaluation, improve reliability and CI/CD, and contribute to testing, monitoring, and internal tools to support customer operations.

Software Engineering Interns will build and maintain a B2B CRM across the full stack, including Next.js and Tailwind CSS frontend interfaces, Node.js and AWS backend services, and MongoDB databases. Responsibilities include developing scalable APIs, optimizing performance, writing secure maintainable code, collaborating with engineering, product, and design teams, and contributing to architecture decisions. This is a remote-first, full-time 12-month internship with potential conversion to a full-time engineering role.

Design, build, test, and maintain low-latency, high-throughput trading services on an Aeron-based platform. Expand trading protocol features, migrate workflows to the new stack, optimize performance and scalability, support production reliability, and collaborate with cross-functional teams while using AI-assisted development tools.

The Quantitative Developer will assist with client onboarding, support, implement and maintain new functionality for portfolio compliance, and improve team documentation.

The Senior Software Engineer at Order.co designs complex features end-to-end, mentors junior engineers, and participates in design reviews while ensuring quality and reliability of systems.

Build a high-performance, low-latency Rust backend and core AI platform for an AI-native trading experience. Implement streaming responses, tool orchestration, caching, secure APIs (auth, rate limits, auditing, tracing), and safe trading action infrastructure (previews, confirmations, idempotency, audit logs). Partner with product and frontend to enable AI-native UX and translate business domain requirements into secure, resilient platform primitives.

Lead architecture and technical direction for an AI-first SaaS product (Growth Studio). Define scalable services, APIs, data flows, and AI-enabled workflows; guide integrations, run architecture/code reviews and POCs; mentor engineers; produce technical documentation; and partner with product, UX, QA, and ops to deliver reliable, secure, and maintainable platform capabilities for GovCon customers.

Develop scalable backend services, APIs, microservices, and distributed systems for a cloud-native fuel card platform. Work with Java or Python, relational and NoSQL databases, Kafka, Elasticsearch, AWS, containerization, CI/CD, and DevOps practices. Responsibilities include system design, coding, testing, deployment, monitoring, troubleshooting, code reviews, and production support while collaborating with product and engineering stakeholders.