Top Backend Engineer Jobs in Seattle, WA

Lead design, development, and maintenance of scalable, secure APIs and integrations. Drive API architecture, governance, automation, and self-service tooling. Ensure reliable, high-performance integrations, mentor and onboard team members, and deliver impactful digital integration features.

Build, operate, and extend data platform and application-layer services enabling secure, self-service data applications at scale. Implement provisioning, CI/CD, access control, integrations, observability, automation, and incident response while contributing to semantic layer and AI-ready tooling roadmaps.

Build and maintain scalable integration and end-to-end test automation frameworks, optimize CI pipelines and test execution, improve test stability and reporting, support engineering teams with triage and best practices, write technical specs/ADRs, participate in on-call rotation, and collaborate cross-functionally to evolve the company test strategy.

Design and implement secure, scalable backend services for speech inference and audio processing. Optimize networking, transcoding, latency, memory, and distributed compute orchestration. Measure and improve system performance, debug complex networking/scheduling/HPC issues, customize services for customers, and partner with Product to deliver features end-to-end.

Build and maintain backend services and APIs for onboarding, accounts, payments, cards, transfers, rewards, FX, KYC and risk. Design reliable, secure, observable systems, integrate with partners and AI services, ensure data integrity and incident handling, and collaborate with product and frontend teams to launch and improve financial products at scale.

Design, build, and maintain backend workflow orchestration and state management for analyzer integrations on the ECL platform. Modernize legacy .NET systems, ensure reliable event-driven operations, collaborate with integration, infrastructure, and QA teams, and preserve workflow behavior during knowledge transfer.

Build and scale a live ML data streaming analytics platform, lead greenfield real-time processing projects (Python/Rust), and design reliable backend services using cloud and orchestration tools.

Design, develop, and maintain high-performance Scala/Java backend services and RESTful APIs. Work with SQL databases, Git, and Maven; support distributed systems; write unit tests; perform requirements analysis, system architecture, and performance optimization; participate in design reviews and system integration. Obtain T4 Public Trust clearance.

The Backend Engineer will develop features across APIs, CLI tools, and billing systems, mentor team members, and set technical direction.

The Backend Software Engineer will develop data ingestion pipelines, implement observability tools, and provide technical support while improving team collaboration.

The Senior Software Engineer will lead and support a team in developing reliable and scalable backend systems, collaborating on product development, and improving infrastructure for secure communication between services.

Develop and operate Java Spring Boot microservices, deploy and manage services on Kubernetes, perform JVM profiling and heap analysis, load test, diagnose memory leaks, OOMs and P99 latency spikes, remediate security vulnerabilities, and maintain GitHub-based CI/CD and branching workflows.

Design, build, and maintain backend workflow orchestration and analyzer integrations for the ECL platform. Manage analyzer state transitions, runtime event handling, and legacy modernization; extract shared .NET libraries, collaborate with integration and QA, and support knowledge transfer.

The backend developer will build backend software focusing on reliable APIs, ensure high-quality output, and collaborate with teams.

Build and ship backend systems and robust architectures for SMB and enterprise restaurant customers. Drive end-to-end development including planning, CI/CD, and productionization. Collaborate on product roadmap, iterate from user feedback, and contribute to team culture and growth.

Design, build, and maintain secure, scalable serverless microservices and integrations on AWS. Optimize databases and CI/CD, manage IaC with Terraform, monitor alerting systems, collaborate with data/product teams, participate in on-call rotation, and drive backend best practices and documentation.

Design, implement, test, and operate core backend services for an AI-native context layer: ingestion, indexing, retrieval APIs, multi-tenant SaaS features, tenant isolation, quotas, and observability. Partner across product and infra, iterate quickly from prototype to production, and own system reliability and architecture.

Design and implement Kotlin backend services and end-to-end systems for Toast POS device management. Lead technical designs, estimations, performance optimization, cross-team collaboration, and software quality practices including modern testing and observability. Mentor peers and drive product roadmap alignment with product, hardware, and QA stakeholders.

The Backend Engineer will develop high-performance trading systems, optimize algorithms, work with distributed architectures, and ensure system reliability and scalability while collaborating on blockchain-related technologies.

As a Backend Engineer, you will develop and scale PostHog's billing system to support growth, implement flexible billing models, and ensure accurate financial reporting. You'll focus on automating processes and handling complex data modeling.

Lead architecture, build, and operate a serverless AWS backend (Python, Lambda, CDK, DynamoDB, S3) supporting APIs, event processing, integrations (EHR/CRM/eCommerce/3PL), observability, security, and compliance. Provide technical leadership, drive platform decisions, identify risks and scalability bottlenecks, and establish backend engineering best practices across systems and teams.

As a Backend Engineer, you'll design and maintain APIs for global money management, collaborate with teams, and mentor engineers.

As a Backend Engineer at Drivetrain, you'll tackle challenging backend application problems, focusing on system design, algorithms, and production services while contributing to a cutting-edge technology stack.

The Backend Engineer will develop intricate backend systems, build performant APIs, and contribute to technology innovation at Entefy.

The Senior Software Engineer will design and implement backend services, manage architectural decisions, and drive improvements in data quality, performance, and reliability, while collaborating across teams to enhance client and provider interactions in mental healthcare.