Top Senior Software Engineer Jobs in Portland, ME

Build and operate accessible, high-performance member-facing web applications using a front-end-first full-stack approach. Contribute to APIs, backend services, data flows, integrations, frontend architecture, testing, observability, and performance improvements. Own projects from concept through production, collaborate with Product, Design, Data, and Clinical teams, improve developer experience, support AI-assisted coding practices, participate in technical reviews and incident follow-up, and mentor engineers.

Develop and maintain software in an agile, test-driven environment using pair programming. Lead technical decisions involving application and data model design, mentor engineers, collaborate cross-functionally with product and design, and ensure application stability and performance. Participate in on-call support and improve system reliability. Use AI developer tools to accelerate development and improve code quality.

The Senior Backend Software Engineer will design and maintain backend systems, optimize performance, ensure security compliance, and mentor junior engineers in a collaborative environment.

The Software Engineer will scale and optimize the platform's infrastructure, manage data layers, and enhance system operations to support growing LLM requests.

As a Software Engineer at OnePay, you will develop and implement features, build scalable products, and work closely with teams to enhance customer experiences.

Develop and optimize distributed systems for syncing customer data, focus on scalability, reliability, and performance for global clients.

Build and evolve scalable backend systems and APIs for a large SaaS platform. Partner with Product, Design, and QA from ideation through deployment, contribute to microservices architecture, improve testing and observability, identify operational risks, and mentor teammates. The role emphasizes reliable, maintainable solutions, strong collaboration, architectural decision-making, and continuous improvement.

Design, architect, develop, test, and support scalable full-stack applications for a high-volume, multi-tenant data platform. Own features from design through delivery, contribute to technical strategy and roadmap development, ensure operational excellence, collaborate across distributed teams, and mentor engineers. Apply cloud-native technologies and AI-assisted development practices while supporting near-real-time analytics and reliable production operations.

Build and ship robust Android features for ClassPass in a large modular codebase. Collaborate with product and design, mentor junior engineers, conduct code reviews, write technical documentation, solve complex problems, improve systems, and contribute to architectural decisions using Kotlin and Jetpack Compose.

Design, build, and maintain scalable brokerage systems supporting international markets. Develop Go-based backend services, gRPC microservices, React interfaces, and vendor integrations. Collaborate with global engineering teams to support multiple languages, currencies, and markets. Lead regional reliability efforts, act as incident commander, troubleshoot production issues, mentor engineers, and contribute to recruitment and cross-functional initiatives. Participate in on-call support and help ensure proactive 24x7 system stability.

Build and operate Yahoo’s developer experience platform, including CI/CD infrastructure, artifact repositories, release pipelines, and ArgoCD GitOps deployments. Develop reusable golden-path workflows, AI-assisted automation, configuration validation, and platform tooling. Support pipeline troubleshooting, artifact management, runner optimization, observability, security practices, and developer adoption through migrations, documentation, office hours, and technical enablement.

Lead architecture and delivery across Rails backends and React frontends, build Node.js and NestJS platform integrations, establish testing and code-quality standards, mentor engineers, review code, and improve reliability, performance, and developer experience. The role requires technical ownership across multiple backend technologies and leadership in AI-assisted development practices.

Build and scale backend systems for a high-traffic donor CRM and payments platform. Own performant SQL and realtime querying, optimize payment flows, implement AI agents, and collaborate across product and design to ship resilient, production-grade features at scale.

Lead architecture and hands-on implementation of a full-stack platform and production AI systems (LLM integration, RAG, agentic workflows). Ship user-facing features across frontend, backend, data pipelines, infrastructure, testing, and monitoring. Set technical direction, tooling, and engineering practices while partnering with product and program teams.

Design, build, and operate scalable, highly concurrent backend services in Go. Architect distributed, fault-tolerant systems, optimize performance and reliability, define APIs and service boundaries, improve observability and operational readiness, and collaborate cross-functionally to support mission-critical autonomous deployments.

Own and advance Chainguard’s internal Developer Platform, including monorepo CI/CD, shared build infrastructure, and Agentic AI tooling. Improve developer experience, build reliability, change throughput, observability, and secure software delivery. Design scalable platform architecture, consolidate build systems, establish standardized delivery blueprints, automate developer toil, partner with engineering teams, and mentor engineers while contributing to technical direction and DORA-aligned outcomes.

Design and build cloud cost-management capabilities, including forecasting, anomaly alerts, cost allocation, data pipelines, transformation models, visualizations, and reusable UI components. Own features end to end from planning through release while improving application reliability and performance. Collaborate closely with engineers and founding team members, contribute to technical design and roadmap decisions, and work pragmatically in a fast-moving distributed startup environment.

Define architecture and technical direction for Catalyst’s distributed data platform, including messaging, state management, reconciliation, streaming, storage, CI/CD, and Kubernetes operations. Build Go and Python frameworks, improve reliability and SLOs, lead incident response, maintain secure dependency and artifact delivery, and develop infrastructure automation. Collaborate across teams and with customers, review designs and code, establish engineering standards, and travel internationally up to 25% to support mission-critical deployments.

Owns the architecture and implementation of high-performance real-time streaming systems, including media ingestion, buffering, relay, packetization, telemetry synchronization, and distribution. Designs protocol modules, resolves interoperability challenges, improves latency and throughput, and maintains production reliability through testing, observability, incident response, and automated deployments. Partners with stakeholders, documents architectural trade-offs, mentors engineers, leads technical rituals, and travels internationally up to 25% to support customer and mission requirements.

Design, implement, and support high-performance storage and query infrastructure handling billions of events. Independently scope and deliver complex projects, optimize query performance, improve reliability, participate in on-call rotations, define KPIs and SLOs, reduce operational toil, debug production issues, collaborate cross-functionally, and mentor engineers.

Design, develop, and maintain scalable web and backend applications, public REST APIs, automated testing frameworks, and cloud-native services. Improve scalability, stability, monitoring, auto-scaling, CI/CD, security, and reliability. Conduct code reviews, troubleshoot production issues, document root causes and operational procedures, and collaborate with distributed engineering teams to deliver fleet-management platforms.

Develop open source SDKs, enterprise APIs, UIs, and backend systems supporting large-scale computer vision datasets. Build scalable, maintainable, performant, and well-tested software for unstructured data and AI workflows. Contribute to enterprise deployments across customer clouds and on-premises environments, while improving tooling, automation, engineering practices, and open source community initiatives in a remote-first team.

The Staff SDET will design and implement automated test frameworks using TypeScript, collaborate with developers, and enhance testing processes within CI/CD pipelines.

Design, build, and optimize GraphQL APIs, gRPC services and SQL queries for a promotions engine. Own complex technical problems, improve production scalability and performance, set up DataDog monitoring, participate in on-call rotations, mentor engineers, and deliver end-to-end features in an agile environment.

Build and operate AlphaSense's identity platform across user management, authentication, and authorization. Design scalable RBAC/ABAC/ReBAC systems, integrate authentication patterns (OAuth/OIDC/SAML), implement SCIM provisioning, and expose GraphQL/gRPC/REST APIs. Partner with security on SOC2/GDPR compliance, drive platform roadmap, champion testing, observability, and reliability, and operate autonomously from North America in close collaboration with the Helsinki team.