Top Backend Engineer Jobs in Denver & Boulder, CO

As a Back-End Engineer, you will design, implement, and maintain core infrastructure while ensuring performance, scalability, and reliability in a fintech environment.

Develop core services using Golang and PostgreSQL, resolve feature issues, ensure software quality, and promote CI/CD practices while collaborating with teams.

Lead architecture and implementation of high-throughput, distributed backend systems for agentic AI and MCP servers. Drive cross-team platform strategy, mentor engineers, own complex multi-quarter projects, and ensure reliability, performance, and operational excellence across microservices and event-driven systems.

Develop and support web services for digital life insurance enrollment, collaborating closely across teams to enhance platform capabilities. Responsible for the quality and maintainability of services, utilizing Python and Java, among other technologies.

The Senior GIS Back-End Engineer will design, build, and maintain geospatial infrastructure, manage spatial data, and support scalable GIS solutions. Responsibilities include troubleshooting Esri systems and collaborating on new analytic capabilities.

You will tackle AI challenges, develop scalable software and collaborate with teams to enhance healthcare navigation using AI solutions.

As a Senior Backend Engineer, you will build APIs and backend systems for an observability platform, focusing on performance, security, and delivering customer results. You will collaborate with product teams and apply best engineering practices.

Design, build, and operate backend systems that serve millions globally, improve cloud infrastructure, and collaborate on new products while ensuring reliability and performance. Also involved in customer interactions to enhance service quality.

Join Zapier's Events Team as a Backend Engineer to enhance foundational event and queuing services, ensuring reliability and scalability. Collaborate with a tight-knit team, advocate for user experience, and manage tasks effectively while exploring new technologies.

As a Software Engineer II in the Credit Decisioning team, you will design and develop backend systems, collaborate with cross-functional teams, and support project delivery and operations.

Responsible for server-side ad insertion service, developing REST APIs, and managing distributed caches. Engage in agile teams with CI/CD practices.

As a Senior Backend Engineer, you will develop and maintain deployment infrastructure for GitLab's self-managed customers, ensuring secure and scalable operations across various environments.

The Backend Engineer II will design, build, test, and maintain backend services for Openly's insurance platform, collaborating on API creation and integration with external services while contributing to architectural decisions.

Build and scale backend and full-stack systems for enterprise customers: design APIs and platform services, improve observability and reliability, respond to incidents, integrate AI features, and collaborate cross-functionally to deliver high-impact enterprise capabilities.

Design, build, and scale highly performant, highly available backend systems for advanced crypto trading instruments. Architect robust services supporting multiple instrument types, collaborate with product and design, and deliver high-value, observable features for traders worldwide.

Lead the design and implementation of backend services for data cataloging and ML training systems, focusing on performance and scalability.

Design and implement secure, scalable backend services for voice agents, integrate AI models and telephony, improve inference, debug concurrent systems, and collaborate with Product to deliver features end-to-end.

The Senior Backend Engineer will design and implement features for a SaaS product, focusing on backend systems, data modeling, and improving team capabilities.

As a Senior Backend Engineer, you'll build features for AI integration, measure productivity changes, and support production operations in a SaaS environment.

Seeking a Senior Backend Engineer to develop backend systems for a Native AI platform, focusing on API design, data integration, and production software systems using Python and Django.

The Senior Backend Engineer, AI Systems will design features for a SaaS environment, manage complex data, and work with AI models. Responsibilities include implementation, support for production, and collaboration within an agile team.

Design and scale core backend APIs and platform primitives for MCP, enabling AI agents to act across Zapier integrations. Build high-availability orchestration, logging, and interfaces between LLM clients and Zapier while partnering with product, design, and cross-functional teams to prioritize performance, security, and developer clarity.

Design and build partner-facing APIs and the Powered by Zapier platform, improve developer tools and docs, ensure scalability and reliability, collaborate cross-functionally, lead technical initiatives, and mentor teammates to support partner integration and embedded automation.

Lead Software Engineer responsible for designing and developing API services, collaborating with business teams, and ensuring high-quality delivery of applications.

Develop and maintain Flask and FastAPI backend services, design API integrations, improve performance and reliability, modernize legacy systems, and participate in on-call rotations to ensure production stability.