Top Backend Engineer Jobs in Denver & Boulder, CO

Build and own integrations and data pipelines connecting healthcare and insurance systems. Develop reliable systems for claims, bills, EOBs, coverage data, portals, webhooks, and inbound files. Normalize and protect PHI, improve observability and data quality, set technical direction, mentor engineers, and use AI-native development practices.

Develop backend systems and continuous delivery platforms that help engineering teams release software independently and safely. Responsibilities include writing tested and extensible code, collaborating with stakeholders, debugging code, participating in code reviews, balancing delivery speed with reliability, and contributing to team growth. The role involves working with distributed systems and technologies including Python or Kotlin, AWS, MySQL, and Kubernetes.

Own and deliver quarterly engineering goals for Affirm’s ML Feature Platform. Design, develop, and launch scalable backend systems, lead engineers through ambiguous problems, collaborate with product and design stakeholders, improve platform reliability and availability, support on-call operations, establish quality standards, and mentor team members. The role focuses on highly available distributed systems supporting machine learning feature creation, storage, serving, and offline backfilling.

Own and deliver goals for ML training and serving infrastructure. Lead engineers through ambiguous, distributed-systems challenges; design, develop, and operate highly available backend platforms; monitor reliability and support on-call operations. Collaborate with product and engineering stakeholders, improve code and design standards, identify and resolve technical issues, and mentor team members. The role focuses on scalable systems that enable production model training and serving.

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, develop, test, deploy, and monitor scalable backend systems for a payroll SaaS product. Build APIs and microservices, collaborate with product and engineering teams, participate in code reviews, and own the full development lifecycle in a continuous delivery environment. The role emphasizes Kotlin, Scala, or Java, cloud platforms, automated testing, relational databases, scalable architecture, and responsible use of AI coding tools.

Own backend engineering goals for Consumer Engineering, lead delivery of scalable systems, collaborate with product, design, and analytics, improve reliability and code quality, resolve technical and business issues, support on-call operations, and mentor engineers.

Own quarterly engineering goals, lead backend engineers through ambiguous problems, collaborate with product and analytics partners, improve system reliability and availability, monitor operational metrics, establish quality standards, and mentor team members. The role requires designing and launching highly available distributed backend systems at scale using Python or Kotlin, AWS, MySQL, and Kubernetes, while driving technical planning and safe changes across large codebases.

Leads cross-team backend initiatives and technical architecture for GitLab’s Core DevOps platform. Responsibilities include modernizing a monolith, establishing service, API, data, security, testing, and observability standards, guiding Go and Kubernetes practices, supporting Rust adoption, participating in incident response, mentoring engineers, reducing technical debt, and advancing AI-assisted engineering workflows.

Design and evolve high-scale backend capabilities for GitLab’s container registry. Drive architecture, performance, reliability, security, APIs, testing, and operational readiness. Mentor engineers, influence technical direction, participate in incident response, and collaborate asynchronously across product, infrastructure, data, frontend, and security teams. Integrate and evaluate agentic AI systems in production engineering workflows while promoting responsible and effective use.

Develop and launch reliable backend systems using Python or Kotlin, AWS, MySQL, and Kubernetes. Break projects into deliverable phases, collaborate with product, design, and analytics teams, monitor system metrics, support availability and on-call operations, debug code, conduct code reviews, and contribute to team growth and interviewing. The role requires 1.5+ years of software engineering experience and strong communication skills.

Build and deliver backend payment-processing features using Kotlin, scalable APIs, microservices, and containerization. Develop automated tests, monitor feature rollouts, collaborate with UX and product management, and participate in design and code reviews. The role supports Toast’s unified payments platform and requires East Coast working hours.

Develop and maintain scalable back-end applications, microservices, RESTful APIs, and distributed software components for a government data analytics platform. Responsibilities include data ingestion and processing enablement, system integration, performance optimization, security implementation, troubleshooting, automated testing, CI/CD, code reviews, and Agile collaboration with multidisciplinary engineering teams.

Lead large-scale initiatives for a high-performance Linux-based network sensor, improving ingestion, scalability, continuous capture, queue reliability, observability, and production diagnostics. Own root cause analysis and postmortems, establish engineering standards, translate business goals into technical plans, and mentor engineers through design and code reviews. The role requires deep Rust expertise, distributed systems experience, concurrent programming, packet capture, message brokers, and cybersecurity best practices.

Architect and operate Affirm’s large-scale Amazon EKS compute platform, including cluster lifecycle, node management, autoscaling, shared components, infrastructure automation, workload safety policies, observability, cost and capacity optimization, and self-service workflows. The role drives technical strategy, mentors engineers, partners cross-functionally, and participates in on-call incident response.

Lead the architecture and technical strategy for Affirm’s high-volume observability platform. Design telemetry pipelines and sampling strategies, improve reliability and cost efficiency, integrate observability into AI-assisted development, and drive platform adoption across engineering teams. Remain hands-on while mentoring six engineers, leading cross-functional initiatives, establishing engineering standards, and overseeing monitoring, alerting, on-call operations, and system availability.

Build and operate GitLab’s Rust-based Knowledge Graph backend supporting SDLC and code indexing, graph queries, MCP endpoints, AI agents, and analytics. Integrate with Rails, ClickHouse, NATS JetStream, and Data Insights systems. Improve reliability, observability, scalability, and operational readiness through testing, metrics, runbooks, alerts, and on-call participation. Collaborate asynchronously across product, data, infrastructure, security, and AI teams while contributing to system design and occasional Ruby or frontend work.

Build and enforce workload safety standards across Affirm’s Amazon EKS fleet. Responsibilities include Kubernetes resource management, workload isolation, disruption handling, cluster capacity analysis, policy automation, production debugging, incident response, fleet-wide rollouts, technical leadership, mentoring, and measuring infrastructure impacts on availability, latency, risk, and cost.

Build and ship backend features end-to-end using Ruby on Rails and SQL. Lead complex technical projects, solve architecture challenges, establish standards, conduct meaningful code reviews, resolve high-risk bugs, document systems, collaborate across engineering teams, and mentor junior engineers.

Develop scalable, secure backend satellite operations software using Python and AWS. Build APIs, integrate cloud services, deploy containerized applications, troubleshoot issues, and optimize performance and costs. Collaborate with frontend engineers, product managers, and cross-functional teams in an Agile Scrum environment. The role may also contribute to generative AI integrations, DevSecOps, CI/CD tooling, and software architecture.

Build and release server-side product features and language-model-powered agents. Define system architecture, data structures, and service interfaces while owning projects from problem definition through production. Partner with founders on product direction, customer requirements, and deployments. The role requires independent judgment, advanced Python expertise, SQL database experience, and practical experience developing language-model or autonomous-agent software.

Design, develop, and maintain scalable PHP/Laravel backend applications and RESTful APIs. Build third-party integrations, optimize PostgreSQL databases, write automated tests, and manage Docker-based deployments across AWS environments. Monitor application health, troubleshoot defects, participate in code reviews, and improve CI/CD pipelines, documentation, and engineering processes while collaborating with product, QA, frontend, and DevOps teams.

Create and evaluate repository-based backend coding tasks for advanced AI models. Responsibilities include designing debugging, feature, API, refactoring, and performance challenges; building reproducible environments and deterministic verifiers; developing reference solutions; evaluating task quality; and documenting requirements and verification criteria.

Designs, builds, and maintains backend APIs, data services, microservices, integrations, data pipelines, and cloud-based solutions. Integrates healthcare, CRM, telephony, SaaS, and AI platforms; develops secure data models and interfaces; troubleshoots complex application and performance issues; and contributes to DevOps, testing, documentation, architecture, and code reviews.

Design, develop, and maintain robust backend systems, APIs, and server-side applications. Integrate third-party payment and banking systems while ensuring performance, security, and scalability. Collaborate with frontend engineers, product managers, and stakeholders to deliver user-focused solutions. The role requires strong backend programming, API, database, and systems integration experience, with cloud, containerization, and CI/CD knowledge preferred.