Top Senior Backend Engineer Jobs in Denver & Boulder, CO

The Senior Backend Engineer II will design, build, and maintain backend services for financial workflows, collaborating with product and engineering teams to enhance system reliability and performance.

Develop, maintain, and evolve a high-throughput, low-latency US sports trading platform. Build scalable microservices on GCP with Kubernetes using Go or Rust. Ensure resilience during peak events, contribute to architecture, mentor junior engineers, collaborate with stakeholders, and adopt CI/CD, IaaS, concurrency debugging, and in-house AI technologies to deliver reliable global services.

The Senior Backend Engineer will enhance data integration infrastructure, manage internal systems, and collaborate with teams to execute engineering tasks for growth initiatives.

As a Senior Software Engineer, you'll own backend systems, mentor team members, and collaborate with product and design to build user-focused solutions.

Design, build, test, and maintain backend services and APIs for an insurance platform. Integrate external services and data providers, improve system stability, performance, and scalability, participate in architecture discussions, mentor teammates, and support internal tooling and deployment practices.

The Senior Backend Engineer will develop the Payroll product, overseeing the entire development cycle from design to deployment, in a microservices architecture.

Design, build, and maintain scalable backend services and APIs for commerce workflows using Python/Django. Improve reliability, performance, and observability, operate AWS deployments, work with PostgreSQL and event-driven architectures (SNS/SQS), modernize legacy systems, and support CI/CD, testing, and production troubleshooting.

Design, build, and own backend services for prediction markets across market lifecycle: creation, trading, oracle resolution, settlement, and payouts. Build low-latency, high-throughput microservices and event-driven systems, drive reliability via SLOs and observability, lead incident response, set technical standards, and mentor engineers while partnering cross-functionally to deliver product and compliance-aligned roadmaps.

As a Senior Software Engineer, you will enhance data pipelines, integrate with EHR systems, and mentor fellow engineers while ensuring scalable and reliable solutions for health technology.

As a Senior Backend Engineer at DuckDuckGo, you'll lead backend projects, mentor engineers, and develop AI-enhanced features for the company's privacy-centric product line.

Lead backend and full-stack work on the Payments team, building multi-gateway integrations (Stripe, PayPal), payment APIs, and customer payment UIs. Ensure secure, compliant (PCI-DSS) payment flows, reliability, observability, and scalability across AWS/Kubernetes microservices. Partner cross-functionally to design architecture, implement settlement/reconciliation, and maintain high availability.

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

Design, build, and operate resilient backend services for dynamic video packaging, manifest generation (HLS/MPEG-DASH), DRM integration, and high-performance server-side ad insertion. Own production reliability, incident response, observability, and performance optimization while integrating AI-driven diagnostics and automation to scale streaming delivery for millions of concurrent viewers.

The Senior Software Engineer will design and develop scalable applications, enhance DevOps practices, and drive continuous improvement within infrastructure and systems.

Design and develop scalable backend services using Java and Spring Boot, build REST APIs, improve performance and maintainability of systems, and collaborate in an Agile environment.

The Senior Backend Engineer will lead the development of backend services, collaborate with teams, and ensure scalable, user-focused solutions while leveraging modern software practices.

The Senior Backend Engineer will maintain a PHP-based payment platform, migrate to Rust, troubleshoot production systems, and contribute to code quality and deployment cycles.

Build and maintain high-quality backend systems in Ruby on Rails (with Hotwire). Develop and maintain CI/CD pipelines, ship well-tested code to production, solve domain-specific problems for solar development and loan servicing, collaborate with product, finance, and operations, and help shape architecture and technical direction.

Design, develop, and maintain scalable, high-performance backend and middleware services on the JVM using Java and Spring/Spring Cloud. Build and enhance microservices, work with AWS and Docker, implement SQL/noSQL solutions (MySQL, Elasticsearch), use Git-based source control and JIRA, collaborate across engineering, design, and QA, and mentor teammates while following best practices and Agile methodologies.

Design, develop, and deliver backend solutions using Java/J2EE and Spring. Implement APIs, web services, database schema, PL/SQL and transactional SQL on DB2/Oracle. Participate in code reviews, testing, CI/CD with Jenkins and uDeploy, code quality analysis with Sonar, and collaborate with DevOps and cross-functional teams to resolve technical roadblocks and improve delivery processes.

Design and implement Java/Spring Boot backend microservices for notification routing, preference sync, webhook ingestion, and batch jobs. Build Pub/Sub consumers with concurrency controls, retry/DLQ, and idempotency; process Avro payloads with schema validation and transformation; integrate with Listrak and internal APIs; implement resilience features and support performance tuning and troubleshooting.

Build and maintain server-side logic, databases, and AWS cloud integrations using Python and Java. Design scalable APIs, optimize performance and security, implement cloud-native architectures, and produce technical documentation for high-availability, distributed systems.

Build and maintain Java/Spring Boot backend microservices for a Notification Hub: routing, preference sync, webhook ingestion, Pub/Sub consumers, Avro schema processing, vendor and internal API integrations, resilience patterns, and operational troubleshooting.

Design, enhance, and scale the ClickPipes data onboarding platform while improving infrastructure, deployment pipelines, and operational processes in a cloud environment.

Responsible for leading a team to improve developer productivity, managing projects, and ensuring high-quality code delivery while collaborating across teams.