Top Senior Full-Stack Engineer Jobs in Denver & Boulder, CO

Develop, maintain and evolve a high-scale US sports trading platform. Build React/TypeScript frontends, backend microservices, optimize SQL and performance, implement CI/CD and automated testing, mentor junior engineers, and collaborate with stakeholders and architecture teams to ensure resilience and integration.

Lead design and build of an AI-native marketing platform: integrations, multi-agent orchestration, UIs, tooling, analytics, CI/CD, auth/multi-tenancy, and production AI agents to automate marketing workflows and drive adoption across teams.

Owner of end-to-end ecommerce features: design, implement, and maintain scalable backend services and performant React/Next.js frontends. Integrate payment gateways and procurement systems (PunchOut), mentor engineers, uphold code quality, and improve platform stability across Node.js, MySQL, and MongoDB.

The Senior Full-Stack Engineer will manage client relationships, design integration solutions, and ensure seamless delivery and optimization of technical workflows, while leveraging AI for efficiency.

Lead frontend-leaning full-stack implementation work for carrier and enterprise integrations: architect reusable UI and API layers, author RFCs, guide technical delivery, enforce testing and security best practices, and partner with cross-functional teams to scope and ship production integrations.

As a Senior Software Engineer in ZT1, you will lead backend system development, manage projects, and influence product direction in a fast-paced, AI-centric environment.

As a Senior Software Engineer, you'll implement collaboration features, support team architecture, work across tech stacks, and improve developer experience.

As a Senior Software Engineer, you'll design, develop, and maintain full-stack applications, utilizing TypeScript and modern frameworks while collaborating cross-functionally to enhance user experience and performance.

Design and build a high-performance, AI-native web trading experience for sophisticated retail traders. Ship core trading workflows (order entry, positions, blotter, watchlists, alerts), implement trustworthy AI UI patterns, collaborate with backend engineers on low-latency contracts, and iterate quickly with users and stakeholders to deliver end-to-end product features.

Build end-to-end full-stack AI features on a Ruby on Rails backend and React frontend, design and run experiments (A/B tests and AI evaluations), implement AI infrastructure for reliable LLM inference, and iterate quickly to scale production-ready LLM-powered products.

The Senior Full-Stack Engineer will develop and ship features across frontend and backend systems, work with various frameworks and databases, write specifications, and improve development processes.

Design, build, and scale data integrations for healthcare systems, collaborating with teams and enhancing functionality while ensuring security and quality.

Own and scale backend systems end-to-end: design, build, and deploy performant APIs and services on AWS using Node/TypeScript. Make architectural tradeoffs, ship production code frequently, establish engineering best practices, and collaborate with product teams while leveraging AI-assisted development.

Design, build, and own end-to-end features for AI-powered finance agents and agent orchestration. Implement integrations with accounting and payment platforms, create dashboards and reporting, ensure security and data integrity, make architectural choices, monitor production, and drive AI-assisted, agentic development workflows.

As a Senior Full Stack Engineer, you'll design and build high-performance web applications, manage end-to-end solutions, and collaborate with teams to enhance user experiences.

As a Senior Fullstack Engineer, you'll architect and build a high-concurrency auction engine, leveraging AI for enhanced user experiences and system reliability.

As a Senior Fullstack Engineer, you'll build financial systems, design lending infrastructure, implement payment integrations, and create user interfaces, ensuring correctness and reliability.

The Senior Full Stack Engineer builds and ships features across frontend and backend systems, working with various frameworks and databases, while collaborating on technical specifications and improving developer experiences.

As a Senior Full-Stack Engineer at ClassDojo, you'll deliver code and features collaboratively, improve systems and practices, and mentor other engineers, all while impacting education for millions of children.

Join the Entefy team as a Senior Full Stack Engineer to build a scalable full stack application enhancing digital interaction for global clients.

Develop applications for game operations, build backend APIs, and frontend components using various technologies, collaborating with teams across the company.

Design and build responsive web applications and APIs, ensuring secure integration and compliance with government standards in an agile environment.

Lead and contribute to an agile scrum team to deliver scalable web application features within sprints. Complete user stories, troubleshoot issues, design and implement complex software solutions, mentor developers, and maintain system architecture, SDLC adherence, and technical documentation. Must meet DHS EOD and fitness requirements.

Lead design and delivery of consumer-facing web applications for school stores and book clubs. Build front-end experiences with React, contribute backend Python work, design APIs and data models, implement testing and monitoring, mentor engineers, and improve development processes across the full software lifecycle.

The Senior Full Stack Developer will build end-to-end solutions, collaborate in a remote environment, and write technical documentation. The role requires expertise in Ruby on Rails and various programming paradigms.