Top Full-Stack Engineer Jobs in Seattle, WA

Senior fullstack engineer to build and scale Brigit's consumer finance platform. Own end-to-end features across frontend (React/React Native/TypeScript) and backend (Java/REST/SQL), optimize database and APIs for high scale, integrate 3rd-party services, implement risk and transaction algorithms, improve CI/CD, testing, monitoring, and internal tooling to support millions of users.

Build and maintain the TypeScript-based Duo Client SDK, including Node.js core packages, public APIs, browser-compatible modules, Vue 3 client components, and platform adapters. Responsibilities include migrating consumers from the GitLab Language Server, managing versioning and deprecation paths, strengthening credential security, optimizing browser performance, writing tests, conducting code reviews, and participating in on-call support.

Build and maintain full-stack software across data models, APIs, user interfaces, workflows, and production systems. Develop accessible, form-driven applications using TypeScript, Node.js, NestJS, React, and Next.js. Design transactional and flexible databases, implement asynchronous processing, and write unit, integration, and end-to-end tests. Participate in code reviews and technical design discussions while improving scalability, security, reliability, and WCAG compliance. Own features end to end with growing autonomy and collaborate with senior engineers and technical leadership.

As a Senior Software Engineer, you will design and build a cutting-edge identity search platform and implement AI systems for defense applications, working closely with cross-functional teams to enhance user workflows and support national security.

Design and implement scalable backend services for payment and transaction workflows using Java. Own end-to-end features from data model and APIs to Angular frontends, improve reliability and performance, refactor legacy systems, troubleshoot production issues, and collaborate with product and design. Leverage AI-assisted development tools responsibly and share best practices across the team.

As a Fullstack Software Engineer, you'll design, develop, and maintain scalable frontend and backend systems while collaborating across teams.

Build and review full-stack software environments for AI training. Develop frontend and backend features, integrate APIs, debug issues across UI and data layers, improve code quality, document technical reasoning, and review peer submissions. The role requires frontend and backend development experience with frameworks such as React or Angular and stacks including Node.js, Python, Java, or Go. Prior AI experience is not required.

Responsible for leading a team of engineers, supporting product development, identifying technical issues, and ensuring high-quality code delivery in backend systems at scale.

Develop and maintain scalable full-stack applications, REST APIs, microservices, and responsive user interfaces. Integrate internal and third-party systems for real-time data synchronization, optimize application performance, implement security controls, and troubleshoot production issues. Collaborate with analysts, quality engineers, program managers, and data science teams to deliver enterprise applications. Support code reviews, CI/CD, deployments, monitoring, and ongoing maintenance.

Design, build and maintain Microsoft Cloud applications using Power Apps/Pages and Azure services. Implement Entra ID authentication, Azure Functions/App Services, Logic Apps and Blob storage. Create Azure Data Factory pipelines and APIs (REST/GraphQL), integrate external services and LLM data pipelines, and ensure performance, security, and scalability while collaborating with customers to turn requirements into streamlined apps.

Build scalable backend-heavy services and applications using C# and .NET, while contributing to Angular and TypeScript UI development. Design and develop REST APIs and microservices, work with relational databases, implement automated testing and CI/CD, and ensure system security, scalability, and performance. Preferred work includes event-driven architectures, messaging systems, NoSQL databases, caching, search technologies, and mentoring engineers or leading technical initiatives.

Build and lead full-stack development for the Polaris platform using React, TypeScript, Django, Python, and PostgreSQL. Own features from architecture through deployment and production support, design secure APIs and integrations, improve performance and observability, maintain automated testing, mentor engineers, review code, and influence technical direction across squads.

Design, implement, and maintain scalable serverless backend services and responsive Next.js front-end components. Build data scrapers and integrations, improve CI/CD and IaC, mentor junior engineers, and collaborate with product and clients to solve complex compliance problems.

Design, build, and maintain production-grade .NET web applications and APIs on Azure. Own full-stack delivery from data models and SQL to front-end components, CI/CD, testing, and architecture. Collaborate with product and delivery teams, participate in code reviews, and ensure secure, observable, well-tested services.

The Full Stack Engineer will design, build, and maintain scalable web applications, impact customer onboarding and integrations, write and review code, and support technical improvements.

Develop and maintain scalable cloud-native web applications using Java, Angular, Docker, APIs, and backend integrations. Build secure services within DevSecOps pipelines and Agile teams, collaborating with engineers, product owners, and stakeholders. The role requires an active Top Secret clearance, AWS and Security+ certifications, and experience with Kafka, Cognito, Temporal, and potentially Oracle. Preferred qualifications include generative AI, RAG, AI agents, vector databases, and federal or DoD experience.

Build and ship full-stack product experiences for Nextdoor’s Rewards & Incentives team using React and Python/Django. Responsibilities include frontend and backend development, entity-relationship modeling, architecture, implementation, testing, iteration, and collaboration with product and design teams. The role involves production software development, agile teamwork, AI-assisted workflows, and eventual participation in an on-call shadow rotation.

Build Haus’s Architect product end to end, developing Python backend services that convert model outputs into recommendations and React interfaces for customer approval. Integrate with platform systems, define API contracts, manage production reliability, and collaborate with product, science, and design. The role requires strong backend engineering, frontend proficiency, cloud operations, database experience, product judgment, testing, monitoring, and effective use of AI coding tools.

Design and develop Java microservices, REST APIs, ingestion pipelines, reconciliation workflows, and JasperReports solutions. Write SQL for data validation and reporting, integrate with legacy Datacom/CICS systems, and perform unit, integration, API, batch, and end-to-end testing. Troubleshoot application and data issues, support UAT and defect triage, modernize PACER reporting, and collaborate with stakeholders, vendors, business users, and cross-functional teams.

Own end-to-end product features for a SaaS platform serving HR, therapists, and employees. Build, scale, and evolve frontend and backend components, lead architecture and standards, collaborate with design and product, and incorporate customer feedback and QA. Work in an early-stage startup environment with product-focused ownership.

Develop and maintain scalable, secure .NET and Angular web applications for a career and college planning SaaS platform. Collaborate with product managers, QA, and stakeholders to translate requirements into technical solutions, troubleshoot complex issues, optimize performance, and adopt relevant technologies. The role requires full-stack expertise across Angular, C#, ASP.NET, MVC, REST APIs, .NET Core, and SQL, along with strong communication and ownership in a remote environment.

Design and build backend systems for finance and accounting modules within an AI-native ERP platform. Responsibilities include modeling invoicing, payments, and financial reporting data; developing Python and FastAPI services with PostgreSQL; building integration APIs; aggregating operational and financial data; and owning greenfield features from design through deployment. The engineer will primarily own backend systems while contributing to React frontend development as needed.

Design and implement backend features in Go, build data pipelines and REST APIs, work with PostgreSQL and AWS, contribute to scalable system design, and optionally develop React.js user-facing features while collaborating in a fast-paced AI-focused startup.

Build and ship end-to-end features for a restaurant operating system, lead architecture and technical execution, define product roadmap with cross-functional teams, and maintain high-quality CI/CD and productionized systems.

Build and own user-facing features and core platform architecture across frontend, backend, and ML pipelines. Integrate AI workflows (LLMs, embeddings) for curriculum generation and automated evaluation. Manage end-to-end development: requirements, design, implementation, CI/CD, testing, observability, and iteration while collaborating with product, design, ML, and customer teams.